java concurrency
This commit is contained in:
DOHA
@@ -0,0 +1,26 @@
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*.class
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0.*
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#folders#
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/target
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/neoDb*
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/data
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/src/main/webapp/WEB-INF/classes
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*/META-INF/*
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.resourceCache
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# Packaged files #
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*.jar
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*.war
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*.ear
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# Files generated by integration tests
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*.txt
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backup-pom.xml
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/bin/
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/temp
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#IntelliJ specific
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.idea/
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*.iml
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@@ -0,0 +1,32 @@
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=========
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## Core Java Concurrency Examples
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### Relevant Articles:
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- [Guide To CompletableFuture](http://www.baeldung.com/java-completablefuture)
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- [A Guide to the Java ExecutorService](http://www.baeldung.com/java-executor-service-tutorial)
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- [Introduction to Thread Pools in Java](http://www.baeldung.com/thread-pool-java-and-guava)
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- [Guide to java.util.concurrent.Future](http://www.baeldung.com/java-future)
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- [Guide to java.util.concurrent.BlockingQueue](http://www.baeldung.com/java-blocking-queue)
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- [Guide to CountDownLatch in Java](http://www.baeldung.com/java-countdown-latch)
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- [A Guide to ConcurrentMap](http://www.baeldung.com/java-concurrent-map)
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- [Guide to PriorityBlockingQueue in Java](http://www.baeldung.com/java-priority-blocking-queue)
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- [Avoiding the ConcurrentModificationException in Java](http://www.baeldung.com/java-concurrentmodificationexception)
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- [Custom Thread Pools In Java 8 Parallel Streams](http://www.baeldung.com/java-8-parallel-streams-custom-threadpool)
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- [Guide to java.util.concurrent.Locks](http://www.baeldung.com/java-concurrent-locks)
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- [An Introduction to ThreadLocal in Java](http://www.baeldung.com/java-threadlocal)
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- [Guide to DelayQueue](http://www.baeldung.com/java-delay-queue)
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- [A Guide to Java SynchronousQueue](http://www.baeldung.com/java-synchronous-queue)
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- [Guide to the Java TransferQueue](http://www.baeldung.com/java-transfer-queue)
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- [Guide to the ConcurrentSkipListMap](http://www.baeldung.com/java-concurrent-skip-list-map)
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||||
- [Difference Between Wait and Sleep in Java](http://www.baeldung.com/java-wait-and-sleep)
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- [LongAdder and LongAccumulator in Java](http://www.baeldung.com/java-longadder-and-longaccumulator)
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- [The Dining Philosophers Problem in Java](http://www.baeldung.com/java-dining-philoshophers)
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||||
- [Guide to CopyOnWriteArrayList](http://www.baeldung.com/java-copy-on-write-arraylist)
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||||
- [Guide to the Java Phaser](http://www.baeldung.com/java-phaser)
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- [Guide to Synchronized Keyword in Java](http://www.baeldung.com/java-synchronized)
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- [An Introduction to Atomic Variables in Java](http://www.baeldung.com/java-atomic-variables)
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- [CyclicBarrier in Java](http://www.baeldung.com/java-cyclic-barrier)
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- [Guide to Volatile Keyword in Java](http://www.baeldung.com/java-volatile)
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- [Overview of the java.util.concurrent](http://www.baeldung.com/java-util-concurrent)
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- [Semaphores in Java](http://www.baeldung.com/java-semaphore)
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@@ -0,0 +1,237 @@
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<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
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xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
|
||||
<modelVersion>4.0.0</modelVersion>
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<groupId>com.baeldung</groupId>
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<artifactId>core-java-concurrency</artifactId>
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<version>0.1.0-SNAPSHOT</version>
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<packaging>jar</packaging>
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<name>core-java-concurrency</name>
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<parent>
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<groupId>com.baeldung</groupId>
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<artifactId>parent-modules</artifactId>
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<version>1.0.0-SNAPSHOT</version>
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||||
</parent>
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<dependencies>
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|
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<!-- utils -->
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<dependency>
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<groupId>com.google.guava</groupId>
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<artifactId>guava</artifactId>
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<version>${guava.version}</version>
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</dependency>
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<dependency>
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<groupId>org.apache.commons</groupId>
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<artifactId>commons-collections4</artifactId>
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<version>${commons-collections4.version}</version>
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</dependency>
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<dependency>
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<groupId>commons-io</groupId>
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<artifactId>commons-io</artifactId>
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<version>${commons-io.version}</version>
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</dependency>
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<dependency>
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<groupId>org.apache.commons</groupId>
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<artifactId>commons-lang3</artifactId>
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<version>${commons-lang3.version}</version>
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</dependency>
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<dependency>
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<groupId>org.apache.commons</groupId>
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<artifactId>commons-math3</artifactId>
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<version>${commons-math3.version}</version>
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</dependency>
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<!-- test scoped -->
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<dependency>
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<groupId>org.assertj</groupId>
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<artifactId>assertj-core</artifactId>
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<version>${assertj.version}</version>
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<scope>test</scope>
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</dependency>
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<dependency>
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<groupId>com.jayway.awaitility</groupId>
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<artifactId>awaitility</artifactId>
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<version>${avaitility.version}</version>
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<scope>test</scope>
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</dependency>
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</dependencies>
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<build>
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<finalName>core-java-concurrency</finalName>
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<resources>
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<resource>
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<directory>src/main/resources</directory>
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<filtering>true</filtering>
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</resource>
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</resources>
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<plugins>
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<plugin>
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<groupId>org.apache.maven.plugins</groupId>
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<artifactId>maven-dependency-plugin</artifactId>
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||||
<executions>
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<execution>
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<id>copy-dependencies</id>
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<phase>prepare-package</phase>
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<goals>
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<goal>copy-dependencies</goal>
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</goals>
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<configuration>
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<outputDirectory>${project.build.directory}/libs</outputDirectory>
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</configuration>
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</execution>
|
||||
</executions>
|
||||
</plugin>
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<plugin>
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<groupId>org.apache.maven.plugins</groupId>
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||||
<artifactId>maven-jar-plugin</artifactId>
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||||
<configuration>
|
||||
<archive>
|
||||
<manifest>
|
||||
<addClasspath>true</addClasspath>
|
||||
<classpathPrefix>libs/</classpathPrefix>
|
||||
<mainClass>org.baeldung.executable.ExecutableMavenJar</mainClass>
|
||||
</manifest>
|
||||
</archive>
|
||||
</configuration>
|
||||
</plugin>
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||||
<plugin>
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||||
<groupId>org.apache.maven.plugins</groupId>
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||||
<artifactId>maven-assembly-plugin</artifactId>
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<executions>
|
||||
<execution>
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<phase>package</phase>
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||||
<goals>
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||||
<goal>single</goal>
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||||
</goals>
|
||||
<configuration>
|
||||
<archiveBaseDirectory>${project.basedir}</archiveBaseDirectory>
|
||||
<archive>
|
||||
<manifest>
|
||||
<mainClass>org.baeldung.executable.ExecutableMavenJar</mainClass>
|
||||
</manifest>
|
||||
</archive>
|
||||
<descriptorRefs>
|
||||
<descriptorRef>jar-with-dependencies</descriptorRef>
|
||||
</descriptorRefs>
|
||||
</configuration>
|
||||
</execution>
|
||||
</executions>
|
||||
</plugin>
|
||||
<plugin>
|
||||
<groupId>org.apache.maven.plugins</groupId>
|
||||
<artifactId>maven-shade-plugin</artifactId>
|
||||
<executions>
|
||||
<execution>
|
||||
<goals>
|
||||
<goal>shade</goal>
|
||||
</goals>
|
||||
<configuration>
|
||||
<shadedArtifactAttached>true</shadedArtifactAttached>
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||||
<transformers>
|
||||
<transformer
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||||
implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
|
||||
<mainClass>org.baeldung.executable.ExecutableMavenJar</mainClass>
|
||||
</transformer>
|
||||
</transformers>
|
||||
</configuration>
|
||||
</execution>
|
||||
</executions>
|
||||
</plugin>
|
||||
<plugin>
|
||||
<groupId>com.jolira</groupId>
|
||||
<artifactId>onejar-maven-plugin</artifactId>
|
||||
<executions>
|
||||
<execution>
|
||||
<configuration>
|
||||
<mainClass>org.baeldung.executable.ExecutableMavenJar</mainClass>
|
||||
<attachToBuild>true</attachToBuild>
|
||||
<filename>${project.build.finalName}-onejar.${project.packaging}</filename>
|
||||
</configuration>
|
||||
<goals>
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||||
<goal>one-jar</goal>
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||||
</goals>
|
||||
</execution>
|
||||
</executions>
|
||||
</plugin>
|
||||
<plugin>
|
||||
<groupId>org.springframework.boot</groupId>
|
||||
<artifactId>spring-boot-maven-plugin</artifactId>
|
||||
<executions>
|
||||
<execution>
|
||||
<goals>
|
||||
<goal>repackage</goal>
|
||||
</goals>
|
||||
<configuration>
|
||||
<classifier>spring-boot</classifier>
|
||||
<mainClass>org.baeldung.executable.ExecutableMavenJar</mainClass>
|
||||
</configuration>
|
||||
</execution>
|
||||
</executions>
|
||||
</plugin>
|
||||
</plugins>
|
||||
|
||||
</build>
|
||||
|
||||
<profiles>
|
||||
<profile>
|
||||
<id>integration</id>
|
||||
<build>
|
||||
<plugins>
|
||||
<plugin>
|
||||
<groupId>org.apache.maven.plugins</groupId>
|
||||
<artifactId>maven-surefire-plugin</artifactId>
|
||||
<executions>
|
||||
<execution>
|
||||
<phase>integration-test</phase>
|
||||
<goals>
|
||||
<goal>test</goal>
|
||||
</goals>
|
||||
<configuration>
|
||||
<excludes>
|
||||
<exclude>**/*ManualTest.java</exclude>
|
||||
</excludes>
|
||||
<includes>
|
||||
<include>**/*IntegrationTest.java</include>
|
||||
</includes>
|
||||
</configuration>
|
||||
</execution>
|
||||
</executions>
|
||||
<configuration>
|
||||
<systemPropertyVariables>
|
||||
<test.mime>json</test.mime>
|
||||
</systemPropertyVariables>
|
||||
</configuration>
|
||||
</plugin>
|
||||
</plugins>
|
||||
</build>
|
||||
</profile>
|
||||
</profiles>
|
||||
|
||||
<properties>
|
||||
|
||||
<!-- util -->
|
||||
<guava.version>21.0</guava.version>
|
||||
<commons-lang3.version>3.5</commons-lang3.version>
|
||||
<commons-math3.version>3.6.1</commons-math3.version>
|
||||
<commons-io.version>2.5</commons-io.version>
|
||||
<commons-collections4.version>4.1</commons-collections4.version>
|
||||
<collections-generic.version>4.01</collections-generic.version>
|
||||
|
||||
<!-- testing -->
|
||||
<assertj.version>3.6.1</assertj.version>
|
||||
<avaitility.version>1.7.0</avaitility.version>
|
||||
|
||||
</properties>
|
||||
</project>
|
||||
+34
@@ -0,0 +1,34 @@
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||||
package com.baeldung.concurrent.Scheduledexecutorservice;
|
||||
|
||||
import java.util.concurrent.Executors;
|
||||
import java.util.concurrent.Future;
|
||||
import java.util.concurrent.ScheduledExecutorService;
|
||||
import java.util.concurrent.ScheduledFuture;
|
||||
import java.util.concurrent.TimeUnit;
|
||||
|
||||
public class ScheduledExecutorServiceDemo {
|
||||
|
||||
public void execute() {
|
||||
ScheduledExecutorService executorService = Executors.newSingleThreadScheduledExecutor();
|
||||
|
||||
ScheduledFuture<?> scheduledFuture = executorService.schedule(() -> {
|
||||
// Task
|
||||
}, 1, TimeUnit.SECONDS);
|
||||
|
||||
executorService.scheduleAtFixedRate(() -> {
|
||||
// Task
|
||||
}, 1, 10, TimeUnit.SECONDS);
|
||||
|
||||
executorService.scheduleWithFixedDelay(() -> {
|
||||
// Task
|
||||
}, 1, 10, TimeUnit.SECONDS);
|
||||
|
||||
Future<String> future = executorService.schedule(() -> {
|
||||
// Task
|
||||
return "Hellow world";
|
||||
}, 1, TimeUnit.SECONDS);
|
||||
|
||||
executorService.shutdown();
|
||||
}
|
||||
|
||||
}
|
||||
+13
@@ -0,0 +1,13 @@
|
||||
package com.baeldung.concurrent.atomic;
|
||||
|
||||
public class SafeCounterWithLock {
|
||||
private volatile int counter;
|
||||
|
||||
public int getValue() {
|
||||
return counter;
|
||||
}
|
||||
|
||||
public synchronized void increment() {
|
||||
counter++;
|
||||
}
|
||||
}
|
||||
+21
@@ -0,0 +1,21 @@
|
||||
package com.baeldung.concurrent.atomic;
|
||||
|
||||
import java.util.concurrent.atomic.AtomicInteger;
|
||||
|
||||
public class SafeCounterWithoutLock {
|
||||
private final AtomicInteger counter = new AtomicInteger(0);
|
||||
|
||||
public int getValue() {
|
||||
return counter.get();
|
||||
}
|
||||
|
||||
public void increment() {
|
||||
while(true) {
|
||||
int existingValue = getValue();
|
||||
int newValue = existingValue + 1;
|
||||
if(counter.compareAndSet(existingValue, newValue)) {
|
||||
return;
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,13 @@
|
||||
package com.baeldung.concurrent.atomic;
|
||||
|
||||
public class UnsafeCounter {
|
||||
int counter;
|
||||
|
||||
public int getValue() {
|
||||
return counter;
|
||||
}
|
||||
|
||||
public void increment() {
|
||||
counter++;
|
||||
}
|
||||
}
|
||||
+24
@@ -0,0 +1,24 @@
|
||||
package com.baeldung.concurrent.blockingqueue;
|
||||
|
||||
import java.util.concurrent.BlockingQueue;
|
||||
import java.util.concurrent.LinkedBlockingQueue;
|
||||
|
||||
public class BlockingQueueUsage {
|
||||
public static void main(String[] args) {
|
||||
int BOUND = 10;
|
||||
int N_PRODUCERS = 4;
|
||||
int N_CONSUMERS = Runtime.getRuntime().availableProcessors();
|
||||
int poisonPill = Integer.MAX_VALUE;
|
||||
int poisonPillPerProducer = N_CONSUMERS / N_PRODUCERS;
|
||||
|
||||
BlockingQueue<Integer> queue = new LinkedBlockingQueue<>(BOUND);
|
||||
|
||||
for (int i = 0; i < N_PRODUCERS; i++) {
|
||||
new Thread(new NumbersProducer(queue, poisonPill, poisonPillPerProducer)).start();
|
||||
}
|
||||
|
||||
for (int j = 0; j < N_CONSUMERS; j++) {
|
||||
new Thread(new NumbersConsumer(queue, poisonPill)).start();
|
||||
}
|
||||
}
|
||||
}
|
||||
+28
@@ -0,0 +1,28 @@
|
||||
package com.baeldung.concurrent.blockingqueue;
|
||||
|
||||
import java.util.concurrent.BlockingQueue;
|
||||
|
||||
public class NumbersConsumer implements Runnable {
|
||||
private final BlockingQueue<Integer> queue;
|
||||
private final int poisonPill;
|
||||
|
||||
NumbersConsumer(BlockingQueue<Integer> queue, int poisonPill) {
|
||||
this.queue = queue;
|
||||
this.poisonPill = poisonPill;
|
||||
}
|
||||
|
||||
public void run() {
|
||||
try {
|
||||
while (true) {
|
||||
Integer number = queue.take();
|
||||
if (number.equals(poisonPill)) {
|
||||
return;
|
||||
}
|
||||
String result = number.toString();
|
||||
System.out.println(Thread.currentThread().getName() + " result: " + result);
|
||||
}
|
||||
} catch (InterruptedException e) {
|
||||
Thread.currentThread().interrupt();
|
||||
}
|
||||
}
|
||||
}
|
||||
+34
@@ -0,0 +1,34 @@
|
||||
package com.baeldung.concurrent.blockingqueue;
|
||||
|
||||
import java.util.concurrent.BlockingQueue;
|
||||
import java.util.concurrent.ThreadLocalRandom;
|
||||
|
||||
public class NumbersProducer implements Runnable {
|
||||
|
||||
private final BlockingQueue<Integer> numbersQueue;
|
||||
private final int poisonPill;
|
||||
private final int poisonPillPerProducer;
|
||||
|
||||
NumbersProducer(BlockingQueue<Integer> numbersQueue, int poisonPill, int poisonPillPerProducer) {
|
||||
this.numbersQueue = numbersQueue;
|
||||
this.poisonPill = poisonPill;
|
||||
this.poisonPillPerProducer = poisonPillPerProducer;
|
||||
}
|
||||
|
||||
public void run() {
|
||||
try {
|
||||
generateNumbers();
|
||||
} catch (InterruptedException e) {
|
||||
Thread.currentThread().interrupt();
|
||||
}
|
||||
}
|
||||
|
||||
private void generateNumbers() throws InterruptedException {
|
||||
for (int i = 0; i < 100; i++) {
|
||||
numbersQueue.put(ThreadLocalRandom.current().nextInt(100));
|
||||
}
|
||||
for (int j = 0; j < poisonPillPerProducer; j++) {
|
||||
numbersQueue.put(poisonPill);
|
||||
}
|
||||
}
|
||||
}
|
||||
+23
@@ -0,0 +1,23 @@
|
||||
package com.baeldung.concurrent.countdownlatch;
|
||||
|
||||
import java.util.List;
|
||||
import java.util.concurrent.CountDownLatch;
|
||||
|
||||
public class BrokenWorker implements Runnable {
|
||||
private final List<String> outputScraper;
|
||||
private final CountDownLatch countDownLatch;
|
||||
|
||||
BrokenWorker(final List<String> outputScraper, final CountDownLatch countDownLatch) {
|
||||
this.outputScraper = outputScraper;
|
||||
this.countDownLatch = countDownLatch;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void run() {
|
||||
if (true) {
|
||||
throw new RuntimeException("Oh dear");
|
||||
}
|
||||
countDownLatch.countDown();
|
||||
outputScraper.add("Counted down");
|
||||
}
|
||||
}
|
||||
+34
@@ -0,0 +1,34 @@
|
||||
package com.baeldung.concurrent.countdownlatch;
|
||||
|
||||
import java.util.List;
|
||||
import java.util.concurrent.CountDownLatch;
|
||||
|
||||
public class WaitingWorker implements Runnable {
|
||||
|
||||
private final List<String> outputScraper;
|
||||
private final CountDownLatch readyThreadCounter;
|
||||
private final CountDownLatch callingThreadBlocker;
|
||||
private final CountDownLatch completedThreadCounter;
|
||||
|
||||
WaitingWorker(final List<String> outputScraper, final CountDownLatch readyThreadCounter, final CountDownLatch callingThreadBlocker, CountDownLatch completedThreadCounter) {
|
||||
|
||||
this.outputScraper = outputScraper;
|
||||
this.readyThreadCounter = readyThreadCounter;
|
||||
this.callingThreadBlocker = callingThreadBlocker;
|
||||
this.completedThreadCounter = completedThreadCounter;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void run() {
|
||||
// Mark this thread as read / started
|
||||
readyThreadCounter.countDown();
|
||||
try {
|
||||
callingThreadBlocker.await();
|
||||
outputScraper.add("Counted down");
|
||||
} catch (InterruptedException e) {
|
||||
e.printStackTrace();
|
||||
} finally {
|
||||
completedThreadCounter.countDown();
|
||||
}
|
||||
}
|
||||
}
|
||||
+22
@@ -0,0 +1,22 @@
|
||||
package com.baeldung.concurrent.countdownlatch;
|
||||
|
||||
import java.util.List;
|
||||
import java.util.concurrent.CountDownLatch;
|
||||
|
||||
public class Worker implements Runnable {
|
||||
private final List<String> outputScraper;
|
||||
private final CountDownLatch countDownLatch;
|
||||
|
||||
Worker(final List<String> outputScraper, final CountDownLatch countDownLatch) {
|
||||
this.outputScraper = outputScraper;
|
||||
this.countDownLatch = countDownLatch;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void run() {
|
||||
// Do some work
|
||||
System.out.println("Doing some logic");
|
||||
outputScraper.add("Counted down");
|
||||
countDownLatch.countDown();
|
||||
}
|
||||
}
|
||||
+77
@@ -0,0 +1,77 @@
|
||||
package com.baeldung.concurrent.cyclicbarrier;
|
||||
|
||||
import java.util.ArrayList;
|
||||
import java.util.Collections;
|
||||
import java.util.List;
|
||||
import java.util.Random;
|
||||
import java.util.concurrent.BrokenBarrierException;
|
||||
import java.util.concurrent.CyclicBarrier;
|
||||
|
||||
public class CyclicBarrierDemo {
|
||||
|
||||
private CyclicBarrier cyclicBarrier;
|
||||
private List<List<Integer>> partialResults = Collections.synchronizedList(new ArrayList<>());
|
||||
private Random random = new Random();
|
||||
private int NUM_PARTIAL_RESULTS;
|
||||
private int NUM_WORKERS;
|
||||
|
||||
private void runSimulation(int numWorkers, int numberOfPartialResults) {
|
||||
NUM_PARTIAL_RESULTS = numberOfPartialResults;
|
||||
NUM_WORKERS = numWorkers;
|
||||
|
||||
cyclicBarrier = new CyclicBarrier(NUM_WORKERS, new AggregatorThread());
|
||||
System.out.println("Spawning " + NUM_WORKERS + " worker threads to compute " + NUM_PARTIAL_RESULTS + " partial results each");
|
||||
for (int i = 0; i < NUM_WORKERS; i++) {
|
||||
Thread worker = new Thread(new NumberCruncherThread());
|
||||
worker.setName("Thread " + i);
|
||||
worker.start();
|
||||
}
|
||||
}
|
||||
|
||||
class NumberCruncherThread implements Runnable {
|
||||
|
||||
@Override
|
||||
public void run() {
|
||||
String thisThreadName = Thread.currentThread().getName();
|
||||
List<Integer> partialResult = new ArrayList<>();
|
||||
for (int i = 0; i < NUM_PARTIAL_RESULTS; i++) {
|
||||
Integer num = random.nextInt(10);
|
||||
System.out.println(thisThreadName + ": Crunching some numbers! Final result - " + num);
|
||||
partialResult.add(num);
|
||||
}
|
||||
partialResults.add(partialResult);
|
||||
try {
|
||||
System.out.println(thisThreadName + " waiting for others to reach barrier.");
|
||||
cyclicBarrier.await();
|
||||
} catch (InterruptedException | BrokenBarrierException e) {
|
||||
e.printStackTrace();
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
class AggregatorThread implements Runnable {
|
||||
|
||||
@Override
|
||||
public void run() {
|
||||
String thisThreadName = Thread.currentThread().getName();
|
||||
System.out.println(thisThreadName + ": Computing final sum of " + NUM_WORKERS + " workers, having " + NUM_PARTIAL_RESULTS + " results each.");
|
||||
int sum = 0;
|
||||
for (List<Integer> threadResult : partialResults) {
|
||||
System.out.print("Adding ");
|
||||
for (Integer partialResult : threadResult) {
|
||||
System.out.print(partialResult + " ");
|
||||
sum += partialResult;
|
||||
}
|
||||
System.out.println();
|
||||
}
|
||||
System.out.println(Thread.currentThread().getName() + ": Final result = " + sum);
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
public static void main(String[] args) {
|
||||
CyclicBarrierDemo play = new CyclicBarrierDemo();
|
||||
play.runSimulation(5, 3);
|
||||
}
|
||||
|
||||
}
|
||||
+24
@@ -0,0 +1,24 @@
|
||||
package com.baeldung.concurrent.cyclicbarrier;
|
||||
|
||||
import java.util.concurrent.CyclicBarrier;
|
||||
|
||||
public class CyclicBarrierExample {
|
||||
|
||||
public void start() {
|
||||
CyclicBarrier cyclicBarrier = new CyclicBarrier(3, () -> {
|
||||
// Task
|
||||
System.out.println("All previous tasks are completed");
|
||||
});
|
||||
|
||||
Thread t1 = new Thread(new Task(cyclicBarrier), "T1");
|
||||
Thread t2 = new Thread(new Task(cyclicBarrier), "T2");
|
||||
Thread t3 = new Thread(new Task(cyclicBarrier), "T3");
|
||||
|
||||
if (!cyclicBarrier.isBroken()) {
|
||||
t1.start();
|
||||
t2.start();
|
||||
t3.start();
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
@@ -0,0 +1,24 @@
|
||||
package com.baeldung.concurrent.cyclicbarrier;
|
||||
|
||||
import java.util.concurrent.BrokenBarrierException;
|
||||
import java.util.concurrent.CyclicBarrier;
|
||||
|
||||
public class Task implements Runnable {
|
||||
|
||||
private CyclicBarrier barrier;
|
||||
|
||||
public Task(CyclicBarrier barrier) {
|
||||
this.barrier = barrier;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void run() {
|
||||
try {
|
||||
System.out.println("Thread : " + Thread.currentThread().getName() + " is waiting");
|
||||
barrier.await();
|
||||
System.out.println("Thread : " + Thread.currentThread().getName() + " is released");
|
||||
} catch (InterruptedException | BrokenBarrierException e) {
|
||||
e.printStackTrace();
|
||||
}
|
||||
}
|
||||
}
|
||||
+35
@@ -0,0 +1,35 @@
|
||||
package com.baeldung.concurrent.delayqueue;
|
||||
|
||||
import com.google.common.primitives.Ints;
|
||||
|
||||
import java.util.concurrent.Delayed;
|
||||
import java.util.concurrent.TimeUnit;
|
||||
|
||||
public class DelayObject implements Delayed {
|
||||
private String data;
|
||||
private long startTime;
|
||||
|
||||
DelayObject(String data, long delayInMilliseconds) {
|
||||
this.data = data;
|
||||
this.startTime = System.currentTimeMillis() + delayInMilliseconds;
|
||||
}
|
||||
|
||||
@Override
|
||||
public long getDelay(TimeUnit unit) {
|
||||
long diff = startTime - System.currentTimeMillis();
|
||||
return unit.convert(diff, TimeUnit.MILLISECONDS);
|
||||
}
|
||||
|
||||
@Override
|
||||
public int compareTo(Delayed o) {
|
||||
return Ints.saturatedCast(this.startTime - ((DelayObject) o).startTime);
|
||||
}
|
||||
|
||||
@Override
|
||||
public String toString() {
|
||||
return "{" +
|
||||
"data='" + data + '\'' +
|
||||
", startTime=" + startTime +
|
||||
'}';
|
||||
}
|
||||
}
|
||||
+30
@@ -0,0 +1,30 @@
|
||||
package com.baeldung.concurrent.delayqueue;
|
||||
|
||||
import java.util.concurrent.BlockingQueue;
|
||||
import java.util.concurrent.atomic.AtomicInteger;
|
||||
|
||||
|
||||
public class DelayQueueConsumer implements Runnable {
|
||||
private BlockingQueue<DelayObject> queue;
|
||||
private final Integer numberOfElementsToTake;
|
||||
final AtomicInteger numberOfConsumedElements = new AtomicInteger();
|
||||
|
||||
DelayQueueConsumer(BlockingQueue<DelayObject> queue, Integer numberOfElementsToTake) {
|
||||
this.queue = queue;
|
||||
this.numberOfElementsToTake = numberOfElementsToTake;
|
||||
}
|
||||
|
||||
|
||||
@Override
|
||||
public void run() {
|
||||
for (int i = 0; i < numberOfElementsToTake; i++) {
|
||||
try {
|
||||
DelayObject object = queue.take();
|
||||
numberOfConsumedElements.incrementAndGet();
|
||||
System.out.println("Consumer take: " + object);
|
||||
} catch (InterruptedException e) {
|
||||
e.printStackTrace();
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
+34
@@ -0,0 +1,34 @@
|
||||
package com.baeldung.concurrent.delayqueue;
|
||||
|
||||
import java.util.UUID;
|
||||
import java.util.concurrent.BlockingQueue;
|
||||
|
||||
|
||||
public class DelayQueueProducer implements Runnable {
|
||||
private BlockingQueue<DelayObject> queue;
|
||||
private final Integer numberOfElementsToProduce;
|
||||
private final Integer delayOfEachProducedMessageMilliseconds;
|
||||
|
||||
DelayQueueProducer(BlockingQueue<DelayObject> queue,
|
||||
Integer numberOfElementsToProduce,
|
||||
Integer delayOfEachProducedMessageMilliseconds) {
|
||||
this.queue = queue;
|
||||
this.numberOfElementsToProduce = numberOfElementsToProduce;
|
||||
this.delayOfEachProducedMessageMilliseconds = delayOfEachProducedMessageMilliseconds;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void run() {
|
||||
for (int i = 0; i < numberOfElementsToProduce; i++) {
|
||||
DelayObject object
|
||||
= new DelayObject(UUID.randomUUID().toString(), delayOfEachProducedMessageMilliseconds);
|
||||
System.out.println("Put object = " + object);
|
||||
try {
|
||||
queue.put(object);
|
||||
Thread.sleep(500);
|
||||
} catch (InterruptedException ie) {
|
||||
ie.printStackTrace();
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
+29
@@ -0,0 +1,29 @@
|
||||
package com.baeldung.concurrent.diningphilosophers;
|
||||
|
||||
public class DiningPhilosophers {
|
||||
|
||||
public static void main(String[] args) throws Exception {
|
||||
|
||||
Philosopher[] philosophers = new Philosopher[5];
|
||||
Object[] forks = new Object[philosophers.length];
|
||||
|
||||
for (int i = 0; i < forks.length; i++) {
|
||||
forks[i] = new Object();
|
||||
}
|
||||
|
||||
for (int i = 0; i < philosophers.length; i++) {
|
||||
|
||||
Object leftFork = forks[i];
|
||||
Object rightFork = forks[(i + 1) % forks.length];
|
||||
|
||||
if (i == philosophers.length - 1) {
|
||||
philosophers[i] = new Philosopher(rightFork, leftFork); // The last philosopher picks up the right fork first
|
||||
} else {
|
||||
philosophers[i] = new Philosopher(leftFork, rightFork);
|
||||
}
|
||||
|
||||
Thread t = new Thread(philosophers[i], "Philosopher " + (i + 1));
|
||||
t.start();
|
||||
}
|
||||
}
|
||||
}
|
||||
+36
@@ -0,0 +1,36 @@
|
||||
package com.baeldung.concurrent.diningphilosophers;
|
||||
|
||||
public class Philosopher implements Runnable {
|
||||
|
||||
private final Object leftFork;
|
||||
private final Object rightFork;
|
||||
|
||||
Philosopher(Object left, Object right) {
|
||||
this.leftFork = left;
|
||||
this.rightFork = right;
|
||||
}
|
||||
|
||||
private void doAction(String action) throws InterruptedException {
|
||||
System.out.println(Thread.currentThread().getName() + " " + action);
|
||||
Thread.sleep(((int) (Math.random() * 100)));
|
||||
}
|
||||
|
||||
@Override
|
||||
public void run() {
|
||||
try {
|
||||
while (true) {
|
||||
doAction(System.nanoTime() + ": Thinking"); // thinking
|
||||
synchronized (leftFork) {
|
||||
doAction(System.nanoTime() + ": Picked up left fork");
|
||||
synchronized (rightFork) {
|
||||
doAction(System.nanoTime() + ": Picked up right fork - eating"); // eating
|
||||
doAction(System.nanoTime() + ": Put down right fork");
|
||||
}
|
||||
doAction(System.nanoTime() + ": Put down left fork. Returning to thinking");
|
||||
}
|
||||
}
|
||||
} catch (InterruptedException e) {
|
||||
Thread.currentThread().interrupt();
|
||||
}
|
||||
}
|
||||
}
|
||||
+14
@@ -0,0 +1,14 @@
|
||||
package com.baeldung.concurrent.executor;
|
||||
|
||||
import java.util.concurrent.Executor;
|
||||
|
||||
public class ExecutorDemo {
|
||||
|
||||
public void execute() {
|
||||
Executor executor = new Invoker();
|
||||
executor.execute(()->{
|
||||
// task to be performed
|
||||
});
|
||||
}
|
||||
|
||||
}
|
||||
@@ -0,0 +1,12 @@
|
||||
package com.baeldung.concurrent.executor;
|
||||
|
||||
import java.util.concurrent.Executor;
|
||||
|
||||
public class Invoker implements Executor {
|
||||
|
||||
@Override
|
||||
public void execute(Runnable r) {
|
||||
r.run();
|
||||
}
|
||||
|
||||
}
|
||||
+27
@@ -0,0 +1,27 @@
|
||||
package com.baeldung.concurrent.executorservice;
|
||||
|
||||
import java.util.concurrent.ExecutorService;
|
||||
import java.util.concurrent.Executors;
|
||||
import java.util.concurrent.TimeUnit;
|
||||
|
||||
public class ExecutorServiceDemo {
|
||||
|
||||
ExecutorService executor = Executors.newFixedThreadPool(10);
|
||||
|
||||
public void execute() {
|
||||
|
||||
executor.submit(() -> {
|
||||
new Task();
|
||||
});
|
||||
|
||||
executor.shutdown();
|
||||
executor.shutdownNow();
|
||||
try {
|
||||
executor.awaitTermination(20l, TimeUnit.NANOSECONDS);
|
||||
} catch (InterruptedException e) {
|
||||
e.printStackTrace();
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
@@ -0,0 +1,10 @@
|
||||
package com.baeldung.concurrent.executorservice;
|
||||
|
||||
public class Task implements Runnable {
|
||||
|
||||
@Override
|
||||
public void run() {
|
||||
// task details
|
||||
}
|
||||
|
||||
}
|
||||
+26
@@ -0,0 +1,26 @@
|
||||
package com.baeldung.concurrent.future;
|
||||
|
||||
import java.util.concurrent.RecursiveTask;
|
||||
|
||||
public class FactorialSquareCalculator extends RecursiveTask<Integer> {
|
||||
private static final long serialVersionUID = 1L;
|
||||
|
||||
final private Integer n;
|
||||
|
||||
FactorialSquareCalculator(Integer n) {
|
||||
this.n = n;
|
||||
}
|
||||
|
||||
@Override
|
||||
protected Integer compute() {
|
||||
if (n <= 1) {
|
||||
return n;
|
||||
}
|
||||
|
||||
FactorialSquareCalculator calculator = new FactorialSquareCalculator(n - 1);
|
||||
|
||||
calculator.fork();
|
||||
|
||||
return n * n + calculator.join();
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,44 @@
|
||||
package com.baeldung.concurrent.future;
|
||||
|
||||
import java.util.concurrent.ExecutionException;
|
||||
import java.util.concurrent.ExecutorService;
|
||||
import java.util.concurrent.Executors;
|
||||
import java.util.concurrent.Future;
|
||||
import java.util.concurrent.TimeUnit;
|
||||
import java.util.concurrent.TimeoutException;
|
||||
|
||||
public class FutureDemo {
|
||||
|
||||
public String invoke() {
|
||||
|
||||
String str = null;
|
||||
|
||||
ExecutorService executorService = Executors.newFixedThreadPool(10);
|
||||
|
||||
Future<String> future = executorService.submit(() -> {
|
||||
// Task
|
||||
Thread.sleep(10000l);
|
||||
return "Hellow world";
|
||||
});
|
||||
|
||||
future.cancel(false);
|
||||
|
||||
try {
|
||||
future.get(20, TimeUnit.SECONDS);
|
||||
} catch (InterruptedException | ExecutionException | TimeoutException e1) {
|
||||
e1.printStackTrace();
|
||||
}
|
||||
|
||||
if (future.isDone() && !future.isCancelled()) {
|
||||
try {
|
||||
str = future.get();
|
||||
} catch (InterruptedException | ExecutionException e) {
|
||||
e.printStackTrace();
|
||||
}
|
||||
}
|
||||
|
||||
return str;
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
+20
@@ -0,0 +1,20 @@
|
||||
package com.baeldung.concurrent.future;
|
||||
|
||||
import java.util.concurrent.ExecutorService;
|
||||
import java.util.concurrent.Future;
|
||||
|
||||
class SquareCalculator {
|
||||
|
||||
private final ExecutorService executor;
|
||||
|
||||
SquareCalculator(ExecutorService executor) {
|
||||
this.executor = executor;
|
||||
}
|
||||
|
||||
Future<Integer> calculate(Integer input) {
|
||||
return executor.submit(() -> {
|
||||
Thread.sleep(1000);
|
||||
return input * input;
|
||||
});
|
||||
}
|
||||
}
|
||||
+83
@@ -0,0 +1,83 @@
|
||||
package com.baeldung.concurrent.locks;
|
||||
|
||||
import org.slf4j.Logger;
|
||||
import org.slf4j.LoggerFactory;
|
||||
|
||||
import java.util.Stack;
|
||||
import java.util.concurrent.ExecutorService;
|
||||
import java.util.concurrent.Executors;
|
||||
import java.util.concurrent.locks.Condition;
|
||||
import java.util.concurrent.locks.ReentrantLock;
|
||||
|
||||
import static java.lang.Thread.sleep;
|
||||
|
||||
public class ReentrantLockWithCondition {
|
||||
|
||||
private static Logger LOG = LoggerFactory.getLogger(ReentrantLockWithCondition.class);
|
||||
|
||||
private Stack<String> stack = new Stack<>();
|
||||
private static final int CAPACITY = 5;
|
||||
|
||||
private ReentrantLock lock = new ReentrantLock();
|
||||
private Condition stackEmptyCondition = lock.newCondition();
|
||||
private Condition stackFullCondition = lock.newCondition();
|
||||
|
||||
private void pushToStack(String item) throws InterruptedException {
|
||||
try {
|
||||
lock.lock();
|
||||
if (stack.size() == CAPACITY) {
|
||||
LOG.info(Thread.currentThread().getName() + " wait on stack full");
|
||||
stackFullCondition.await();
|
||||
}
|
||||
LOG.info("Pushing the item " + item);
|
||||
stack.push(item);
|
||||
stackEmptyCondition.signalAll();
|
||||
} finally {
|
||||
lock.unlock();
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
private String popFromStack() throws InterruptedException {
|
||||
try {
|
||||
lock.lock();
|
||||
if (stack.size() == 0) {
|
||||
LOG.info(Thread.currentThread().getName() + " wait on stack empty");
|
||||
stackEmptyCondition.await();
|
||||
}
|
||||
return stack.pop();
|
||||
} finally {
|
||||
stackFullCondition.signalAll();
|
||||
lock.unlock();
|
||||
}
|
||||
}
|
||||
|
||||
public static void main(String[] args) {
|
||||
final int threadCount = 2;
|
||||
ReentrantLockWithCondition object = new ReentrantLockWithCondition();
|
||||
final ExecutorService service = Executors.newFixedThreadPool(threadCount);
|
||||
service.execute(() -> {
|
||||
for (int i = 0; i < 10; i++) {
|
||||
try {
|
||||
object.pushToStack("Item " + i);
|
||||
} catch (InterruptedException e) {
|
||||
e.printStackTrace();
|
||||
}
|
||||
}
|
||||
|
||||
});
|
||||
|
||||
service.execute(() -> {
|
||||
for (int i = 0; i < 10; i++) {
|
||||
try {
|
||||
LOG.info("Item popped " + object.popFromStack());
|
||||
} catch (InterruptedException e) {
|
||||
e.printStackTrace();
|
||||
}
|
||||
}
|
||||
|
||||
});
|
||||
|
||||
service.shutdown();
|
||||
}
|
||||
}
|
||||
+88
@@ -0,0 +1,88 @@
|
||||
package com.baeldung.concurrent.locks;
|
||||
|
||||
import org.slf4j.Logger;
|
||||
import org.slf4j.LoggerFactory;
|
||||
|
||||
import java.util.concurrent.ExecutorService;
|
||||
import java.util.concurrent.Executors;
|
||||
import java.util.concurrent.TimeUnit;
|
||||
import java.util.concurrent.locks.ReentrantLock;
|
||||
|
||||
import static java.lang.Thread.sleep;
|
||||
|
||||
public class SharedObjectWithLock {
|
||||
|
||||
private static final Logger LOG = LoggerFactory.getLogger(SharedObjectWithLock.class);
|
||||
|
||||
private ReentrantLock lock = new ReentrantLock(true);
|
||||
|
||||
private int counter = 0;
|
||||
|
||||
void perform() {
|
||||
|
||||
lock.lock();
|
||||
LOG.info("Thread - " + Thread.currentThread().getName() + " acquired the lock");
|
||||
try {
|
||||
LOG.info("Thread - " + Thread.currentThread().getName() + " processing");
|
||||
counter++;
|
||||
} catch (Exception exception) {
|
||||
LOG.error(" Interrupted Exception ", exception);
|
||||
} finally {
|
||||
lock.unlock();
|
||||
LOG.info("Thread - " + Thread.currentThread().getName() + " released the lock");
|
||||
}
|
||||
}
|
||||
|
||||
private void performTryLock() {
|
||||
|
||||
LOG.info("Thread - " + Thread.currentThread().getName() + " attempting to acquire the lock");
|
||||
try {
|
||||
boolean isLockAcquired = lock.tryLock(2, TimeUnit.SECONDS);
|
||||
if (isLockAcquired) {
|
||||
try {
|
||||
LOG.info("Thread - " + Thread.currentThread().getName() + " acquired the lock");
|
||||
|
||||
LOG.info("Thread - " + Thread.currentThread().getName() + " processing");
|
||||
sleep(1000);
|
||||
} finally {
|
||||
lock.unlock();
|
||||
LOG.info("Thread - " + Thread.currentThread().getName() + " released the lock");
|
||||
|
||||
}
|
||||
}
|
||||
} catch (InterruptedException exception) {
|
||||
LOG.error(" Interrupted Exception ", exception);
|
||||
}
|
||||
LOG.info("Thread - " + Thread.currentThread().getName() + " could not acquire the lock");
|
||||
}
|
||||
|
||||
public ReentrantLock getLock() {
|
||||
return lock;
|
||||
}
|
||||
|
||||
boolean isLocked() {
|
||||
return lock.isLocked();
|
||||
}
|
||||
|
||||
boolean hasQueuedThreads() {
|
||||
return lock.hasQueuedThreads();
|
||||
}
|
||||
|
||||
int getCounter() {
|
||||
return counter;
|
||||
}
|
||||
|
||||
public static void main(String[] args) {
|
||||
|
||||
final int threadCount = 2;
|
||||
final ExecutorService service = Executors.newFixedThreadPool(threadCount);
|
||||
final SharedObjectWithLock object = new SharedObjectWithLock();
|
||||
|
||||
service.execute(object::perform);
|
||||
service.execute(object::performTryLock);
|
||||
|
||||
service.shutdown();
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
+104
@@ -0,0 +1,104 @@
|
||||
package com.baeldung.concurrent.locks;
|
||||
|
||||
import org.slf4j.Logger;
|
||||
import org.slf4j.LoggerFactory;
|
||||
|
||||
import java.util.HashMap;
|
||||
import java.util.Map;
|
||||
import java.util.concurrent.ExecutorService;
|
||||
import java.util.concurrent.Executors;
|
||||
import java.util.concurrent.locks.StampedLock;
|
||||
|
||||
import static java.lang.Thread.sleep;
|
||||
|
||||
public class StampedLockDemo {
|
||||
private Map<String, String> map = new HashMap<>();
|
||||
private Logger logger = LoggerFactory.getLogger(StampedLockDemo.class);
|
||||
|
||||
private final StampedLock lock = new StampedLock();
|
||||
|
||||
public void put(String key, String value) throws InterruptedException {
|
||||
long stamp = lock.writeLock();
|
||||
|
||||
try {
|
||||
logger.info(Thread.currentThread().getName() + " acquired the write lock with stamp " + stamp);
|
||||
map.put(key, value);
|
||||
} finally {
|
||||
lock.unlockWrite(stamp);
|
||||
logger.info(Thread.currentThread().getName() + " unlocked the write lock with stamp " + stamp);
|
||||
}
|
||||
}
|
||||
|
||||
public String get(String key) throws InterruptedException {
|
||||
long stamp = lock.readLock();
|
||||
logger.info(Thread.currentThread().getName() + " acquired the read lock with stamp " + stamp);
|
||||
try {
|
||||
sleep(5000);
|
||||
return map.get(key);
|
||||
|
||||
} finally {
|
||||
lock.unlockRead(stamp);
|
||||
logger.info(Thread.currentThread().getName() + " unlocked the read lock with stamp " + stamp);
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
private String readWithOptimisticLock(String key) throws InterruptedException {
|
||||
long stamp = lock.tryOptimisticRead();
|
||||
String value = map.get(key);
|
||||
|
||||
if (!lock.validate(stamp)) {
|
||||
stamp = lock.readLock();
|
||||
try {
|
||||
sleep(5000);
|
||||
return map.get(key);
|
||||
|
||||
} finally {
|
||||
lock.unlock(stamp);
|
||||
logger.info(Thread.currentThread().getName() + " unlocked the read lock with stamp " + stamp);
|
||||
|
||||
}
|
||||
}
|
||||
return value;
|
||||
}
|
||||
|
||||
public static void main(String[] args) {
|
||||
final int threadCount = 4;
|
||||
final ExecutorService service = Executors.newFixedThreadPool(threadCount);
|
||||
StampedLockDemo object = new StampedLockDemo();
|
||||
|
||||
Runnable writeTask = () -> {
|
||||
|
||||
try {
|
||||
object.put("key1", "value1");
|
||||
} catch (InterruptedException e) {
|
||||
e.printStackTrace();
|
||||
}
|
||||
};
|
||||
Runnable readTask = () -> {
|
||||
|
||||
try {
|
||||
object.get("key1");
|
||||
} catch (InterruptedException e) {
|
||||
e.printStackTrace();
|
||||
}
|
||||
};
|
||||
Runnable readOptimisticTask = () -> {
|
||||
|
||||
try {
|
||||
object.readWithOptimisticLock("key1");
|
||||
} catch (InterruptedException e) {
|
||||
e.printStackTrace();
|
||||
}
|
||||
};
|
||||
service.submit(writeTask);
|
||||
service.submit(writeTask);
|
||||
service.submit(readTask);
|
||||
service.submit(readOptimisticTask);
|
||||
|
||||
service.shutdown();
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
+120
@@ -0,0 +1,120 @@
|
||||
package com.baeldung.concurrent.locks;
|
||||
|
||||
import org.slf4j.Logger;
|
||||
import org.slf4j.LoggerFactory;
|
||||
|
||||
import java.util.HashMap;
|
||||
import java.util.Map;
|
||||
import java.util.concurrent.ExecutorService;
|
||||
import java.util.concurrent.Executors;
|
||||
import java.util.concurrent.locks.Lock;
|
||||
import java.util.concurrent.locks.ReadWriteLock;
|
||||
import java.util.concurrent.locks.ReentrantReadWriteLock;
|
||||
|
||||
import static java.lang.Thread.sleep;
|
||||
|
||||
public class SynchronizedHashMapWithRWLock {
|
||||
|
||||
private static Map<String, String> syncHashMap = new HashMap<>();
|
||||
private Logger logger = LoggerFactory.getLogger(SynchronizedHashMapWithRWLock.class);
|
||||
|
||||
private final ReadWriteLock lock = new ReentrantReadWriteLock();
|
||||
private final Lock readLock = lock.readLock();
|
||||
private final Lock writeLock = lock.writeLock();
|
||||
|
||||
public void put(String key, String value) throws InterruptedException {
|
||||
|
||||
try {
|
||||
writeLock.lock();
|
||||
logger.info(Thread.currentThread().getName() + " writing");
|
||||
syncHashMap.put(key, value);
|
||||
sleep(1000);
|
||||
} finally {
|
||||
writeLock.unlock();
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
public String get(String key) {
|
||||
try {
|
||||
readLock.lock();
|
||||
logger.info(Thread.currentThread().getName() + " reading");
|
||||
return syncHashMap.get(key);
|
||||
} finally {
|
||||
readLock.unlock();
|
||||
}
|
||||
}
|
||||
|
||||
public String remove(String key) {
|
||||
try {
|
||||
writeLock.lock();
|
||||
return syncHashMap.remove(key);
|
||||
} finally {
|
||||
writeLock.unlock();
|
||||
}
|
||||
}
|
||||
|
||||
public boolean containsKey(String key) {
|
||||
try {
|
||||
readLock.lock();
|
||||
return syncHashMap.containsKey(key);
|
||||
} finally {
|
||||
readLock.unlock();
|
||||
}
|
||||
}
|
||||
|
||||
boolean isReadLockAvailable() {
|
||||
return readLock.tryLock();
|
||||
}
|
||||
|
||||
public static void main(String[] args) throws InterruptedException {
|
||||
|
||||
final int threadCount = 3;
|
||||
final ExecutorService service = Executors.newFixedThreadPool(threadCount);
|
||||
SynchronizedHashMapWithRWLock object = new SynchronizedHashMapWithRWLock();
|
||||
|
||||
service.execute(new Thread(new Writer(object), "Writer"));
|
||||
service.execute(new Thread(new Reader(object), "Reader1"));
|
||||
service.execute(new Thread(new Reader(object), "Reader2"));
|
||||
|
||||
service.shutdown();
|
||||
}
|
||||
|
||||
private static class Reader implements Runnable {
|
||||
|
||||
SynchronizedHashMapWithRWLock object;
|
||||
|
||||
Reader(SynchronizedHashMapWithRWLock object) {
|
||||
this.object = object;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void run() {
|
||||
for (int i = 0; i < 10; i++) {
|
||||
object.get("key" + i);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
private static class Writer implements Runnable {
|
||||
|
||||
SynchronizedHashMapWithRWLock object;
|
||||
|
||||
public Writer(SynchronizedHashMapWithRWLock object) {
|
||||
this.object = object;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void run() {
|
||||
for (int i = 0; i < 10; i++) {
|
||||
try {
|
||||
object.put("key" + i, "value" + i);
|
||||
sleep(1000);
|
||||
} catch (InterruptedException e) {
|
||||
e.printStackTrace();
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
+27
@@ -0,0 +1,27 @@
|
||||
package com.baeldung.concurrent.phaser;
|
||||
|
||||
import java.util.concurrent.Phaser;
|
||||
|
||||
class LongRunningAction implements Runnable {
|
||||
private String threadName;
|
||||
private Phaser ph;
|
||||
|
||||
LongRunningAction(String threadName, Phaser ph) {
|
||||
this.threadName = threadName;
|
||||
this.ph = ph;
|
||||
ph.register();
|
||||
}
|
||||
|
||||
@Override
|
||||
public void run() {
|
||||
System.out.println("This is phase " + ph.getPhase());
|
||||
System.out.println("Thread " + threadName + " before long running action");
|
||||
ph.arriveAndAwaitAdvance();
|
||||
try {
|
||||
Thread.sleep(20);
|
||||
} catch (InterruptedException e) {
|
||||
e.printStackTrace();
|
||||
}
|
||||
ph.arriveAndDeregister();
|
||||
}
|
||||
}
|
||||
+22
@@ -0,0 +1,22 @@
|
||||
package com.baeldung.concurrent.semaphore;
|
||||
|
||||
import java.util.concurrent.Semaphore;
|
||||
|
||||
public class SemaPhoreDemo {
|
||||
|
||||
static Semaphore semaphore = new Semaphore(10);
|
||||
|
||||
public void execute() throws InterruptedException {
|
||||
|
||||
System.out.println("Available permit : " + semaphore.availablePermits());
|
||||
System.out.println("Number of threads waiting to acquire: " + semaphore.getQueueLength());
|
||||
|
||||
if (semaphore.tryAcquire()) {
|
||||
semaphore.acquire();
|
||||
// perform some critical operations
|
||||
semaphore.release();
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
+31
@@ -0,0 +1,31 @@
|
||||
package com.baeldung.concurrent.semaphores;
|
||||
|
||||
import java.util.concurrent.Semaphore;
|
||||
|
||||
class CounterUsingMutex {
|
||||
|
||||
private final Semaphore mutex;
|
||||
private int count;
|
||||
|
||||
CounterUsingMutex() {
|
||||
mutex = new Semaphore(1);
|
||||
count = 0;
|
||||
}
|
||||
|
||||
void increase() throws InterruptedException {
|
||||
mutex.acquire();
|
||||
this.count = this.count + 1;
|
||||
Thread.sleep(1000);
|
||||
mutex.release();
|
||||
|
||||
}
|
||||
|
||||
int getCount() {
|
||||
return this.count;
|
||||
}
|
||||
|
||||
boolean hasQueuedThreads() {
|
||||
return mutex.hasQueuedThreads();
|
||||
}
|
||||
|
||||
}
|
||||
+23
@@ -0,0 +1,23 @@
|
||||
package com.baeldung.concurrent.semaphores;
|
||||
|
||||
import java.util.concurrent.TimeUnit;
|
||||
|
||||
import org.apache.commons.lang3.concurrent.TimedSemaphore;
|
||||
|
||||
class DelayQueueUsingTimedSemaphore {
|
||||
|
||||
private final TimedSemaphore semaphore;
|
||||
|
||||
DelayQueueUsingTimedSemaphore(long period, int slotLimit) {
|
||||
semaphore = new TimedSemaphore(period, TimeUnit.SECONDS, slotLimit);
|
||||
}
|
||||
|
||||
boolean tryAdd() {
|
||||
return semaphore.tryAcquire();
|
||||
}
|
||||
|
||||
int availableSlots() {
|
||||
return semaphore.getAvailablePermits();
|
||||
}
|
||||
|
||||
}
|
||||
+25
@@ -0,0 +1,25 @@
|
||||
package com.baeldung.concurrent.semaphores;
|
||||
|
||||
import java.util.concurrent.Semaphore;
|
||||
|
||||
class LoginQueueUsingSemaphore {
|
||||
|
||||
private final Semaphore semaphore;
|
||||
|
||||
LoginQueueUsingSemaphore(int slotLimit) {
|
||||
semaphore = new Semaphore(slotLimit);
|
||||
}
|
||||
|
||||
boolean tryLogin() {
|
||||
return semaphore.tryAcquire();
|
||||
}
|
||||
|
||||
void logout() {
|
||||
semaphore.release();
|
||||
}
|
||||
|
||||
int availableSlots() {
|
||||
return semaphore.availablePermits();
|
||||
}
|
||||
|
||||
}
|
||||
@@ -0,0 +1,21 @@
|
||||
package com.baeldung.concurrent.skiplist;
|
||||
|
||||
import java.time.ZonedDateTime;
|
||||
|
||||
class Event {
|
||||
private final ZonedDateTime eventTime;
|
||||
private final String content;
|
||||
|
||||
Event(ZonedDateTime eventTime, String content) {
|
||||
this.eventTime = eventTime;
|
||||
this.content = content;
|
||||
}
|
||||
|
||||
ZonedDateTime getEventTime() {
|
||||
return eventTime;
|
||||
}
|
||||
|
||||
String getContent() {
|
||||
return content;
|
||||
}
|
||||
}
|
||||
+29
@@ -0,0 +1,29 @@
|
||||
package com.baeldung.concurrent.skiplist;
|
||||
|
||||
import java.time.ZonedDateTime;
|
||||
import java.util.Comparator;
|
||||
import java.util.concurrent.ConcurrentNavigableMap;
|
||||
import java.util.concurrent.ConcurrentSkipListMap;
|
||||
|
||||
class EventWindowSort {
|
||||
private final ConcurrentSkipListMap<ZonedDateTime, String> events
|
||||
= new ConcurrentSkipListMap<>(Comparator.comparingLong(value -> value.toInstant().toEpochMilli()));
|
||||
|
||||
void acceptEvent(Event event) {
|
||||
events.put(event.getEventTime(), event.getContent());
|
||||
}
|
||||
|
||||
ConcurrentNavigableMap<ZonedDateTime, String> getEventsFromLastMinute() {
|
||||
return events.tailMap(ZonedDateTime
|
||||
.now()
|
||||
.minusMinutes(1));
|
||||
}
|
||||
|
||||
ConcurrentNavigableMap<ZonedDateTime, String> getEventsOlderThatOneMinute() {
|
||||
return events.headMap(ZonedDateTime
|
||||
.now()
|
||||
.minusMinutes(1));
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
@@ -0,0 +1,27 @@
|
||||
package com.baeldung.concurrent.sleepwait;
|
||||
|
||||
import org.slf4j.Logger;
|
||||
import org.slf4j.LoggerFactory;
|
||||
|
||||
/***
|
||||
* Example of waking up a waiting thread
|
||||
*/
|
||||
public class ThreadA {
|
||||
|
||||
private static final Logger LOG = LoggerFactory.getLogger(ThreadA.class);
|
||||
|
||||
private static final ThreadB b = new ThreadB();
|
||||
|
||||
public static void main(String... args) throws InterruptedException {
|
||||
b.start();
|
||||
|
||||
synchronized (b) {
|
||||
while (b.sum == 0) {
|
||||
LOG.debug("Waiting for ThreadB to complete...");
|
||||
b.wait();
|
||||
}
|
||||
|
||||
LOG.debug("ThreadB has completed. Sum from that thread is: " + b.sum);
|
||||
}
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,20 @@
|
||||
package com.baeldung.concurrent.sleepwait;
|
||||
|
||||
/***
|
||||
* Example of waking up a waiting thread
|
||||
*/
|
||||
class ThreadB extends Thread {
|
||||
int sum;
|
||||
|
||||
@Override
|
||||
public void run() {
|
||||
synchronized (this) {
|
||||
int i = 0;
|
||||
while (i < 100000) {
|
||||
sum += i;
|
||||
i++;
|
||||
}
|
||||
notify();
|
||||
}
|
||||
}
|
||||
}
|
||||
+29
@@ -0,0 +1,29 @@
|
||||
package com.baeldung.concurrent.sleepwait;
|
||||
|
||||
import org.slf4j.Logger;
|
||||
import org.slf4j.LoggerFactory;
|
||||
|
||||
/***
|
||||
* Example of wait() and sleep() methods
|
||||
*/
|
||||
public class WaitSleepExample {
|
||||
|
||||
private static final Logger LOG = LoggerFactory.getLogger(WaitSleepExample.class);
|
||||
|
||||
private static final Object LOCK = new Object();
|
||||
|
||||
public static void main(String... args) throws InterruptedException {
|
||||
sleepWaitInSynchronizedBlocks();
|
||||
}
|
||||
|
||||
private static void sleepWaitInSynchronizedBlocks() throws InterruptedException {
|
||||
Thread.sleep(1000); // called on the thread
|
||||
LOG.debug("Thread '" + Thread.currentThread().getName() + "' is woken after sleeping for 1 second");
|
||||
|
||||
synchronized (LOCK) {
|
||||
LOCK.wait(1000); // called on the object, synchronization required
|
||||
LOG.debug("Object '" + LOCK + "' is woken after waiting for 1 second");
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
+35
@@ -0,0 +1,35 @@
|
||||
package com.baeldung.concurrent.synchronize;
|
||||
|
||||
public class BaeldungSynchronizedBlocks {
|
||||
|
||||
private int count = 0;
|
||||
private static int staticCount = 0;
|
||||
|
||||
void performSynchronisedTask() {
|
||||
synchronized (this) {
|
||||
setCount(getCount() + 1);
|
||||
}
|
||||
}
|
||||
|
||||
static void performStaticSyncTask() {
|
||||
synchronized (BaeldungSynchronizedBlocks.class) {
|
||||
setStaticCount(getStaticCount() + 1);
|
||||
}
|
||||
}
|
||||
|
||||
public int getCount() {
|
||||
return count;
|
||||
}
|
||||
|
||||
public void setCount(int count) {
|
||||
this.count = count;
|
||||
}
|
||||
|
||||
static int getStaticCount() {
|
||||
return staticCount;
|
||||
}
|
||||
|
||||
private static void setStaticCount(int staticCount) {
|
||||
BaeldungSynchronizedBlocks.staticCount = staticCount;
|
||||
}
|
||||
}
|
||||
+37
@@ -0,0 +1,37 @@
|
||||
package com.baeldung.concurrent.synchronize;
|
||||
|
||||
public class BaeldungSynchronizedMethods {
|
||||
|
||||
private int sum = 0;
|
||||
private int syncSum = 0;
|
||||
|
||||
static int staticSum = 0;
|
||||
|
||||
void calculate() {
|
||||
setSum(getSum() + 1);
|
||||
}
|
||||
|
||||
synchronized void synchronisedCalculate() {
|
||||
setSyncSum(getSyncSum() + 1);
|
||||
}
|
||||
|
||||
static synchronized void syncStaticCalculate() {
|
||||
staticSum = staticSum + 1;
|
||||
}
|
||||
|
||||
public int getSum() {
|
||||
return sum;
|
||||
}
|
||||
|
||||
public void setSum(int sum) {
|
||||
this.sum = sum;
|
||||
}
|
||||
|
||||
int getSyncSum() {
|
||||
return syncSum;
|
||||
}
|
||||
|
||||
private void setSyncSum(int syncSum) {
|
||||
this.syncSum = syncSum;
|
||||
}
|
||||
}
|
||||
+23
@@ -0,0 +1,23 @@
|
||||
package com.baeldung.concurrent.threadfactory;
|
||||
|
||||
import java.util.concurrent.ThreadFactory;
|
||||
|
||||
public class BaeldungThreadFactory implements ThreadFactory {
|
||||
|
||||
private int threadId;
|
||||
private String name;
|
||||
|
||||
public BaeldungThreadFactory(String name) {
|
||||
threadId = 1;
|
||||
this.name = name;
|
||||
}
|
||||
|
||||
@Override
|
||||
public Thread newThread(Runnable r) {
|
||||
Thread t = new Thread(r, name + "-Thread_" + threadId);
|
||||
System.out.println("created new thread with id : " + threadId + " and name : " + t.getName());
|
||||
threadId++;
|
||||
return t;
|
||||
}
|
||||
|
||||
}
|
||||
@@ -0,0 +1,13 @@
|
||||
package com.baeldung.concurrent.threadfactory;
|
||||
|
||||
public class Demo {
|
||||
|
||||
public void execute() {
|
||||
BaeldungThreadFactory factory = new BaeldungThreadFactory("BaeldungThreadFactory");
|
||||
for (int i = 0; i < 10; i++) {
|
||||
Thread t = factory.newThread(new Task());
|
||||
t.start();
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
@@ -0,0 +1,10 @@
|
||||
package com.baeldung.concurrent.threadfactory;
|
||||
|
||||
public class Task implements Runnable {
|
||||
|
||||
@Override
|
||||
public void run() {
|
||||
// task details
|
||||
}
|
||||
|
||||
}
|
||||
+13
@@ -0,0 +1,13 @@
|
||||
package com.baeldung.concurrent.volatilekeyword;
|
||||
|
||||
|
||||
public class SharedObject {
|
||||
private volatile int count=0;
|
||||
|
||||
void increamentCount(){
|
||||
count++;
|
||||
}
|
||||
public int getCount(){
|
||||
return count;
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,17 @@
|
||||
package com.baeldung.threadlocal;
|
||||
|
||||
|
||||
public class Context {
|
||||
private final String userName;
|
||||
|
||||
public Context(String userName) {
|
||||
this.userName = userName;
|
||||
}
|
||||
|
||||
@Override
|
||||
public String toString() {
|
||||
return "Context{" +
|
||||
"userNameSecret='" + userName + '\'' +
|
||||
'}';
|
||||
}
|
||||
}
|
||||
+21
@@ -0,0 +1,21 @@
|
||||
package com.baeldung.threadlocal;
|
||||
|
||||
|
||||
import java.util.Map;
|
||||
import java.util.concurrent.ConcurrentHashMap;
|
||||
|
||||
public class SharedMapWithUserContext implements Runnable {
|
||||
public final static Map<Integer, Context> userContextPerUserId = new ConcurrentHashMap<>();
|
||||
private final Integer userId;
|
||||
private UserRepository userRepository = new UserRepository();
|
||||
|
||||
public SharedMapWithUserContext(Integer userId) {
|
||||
this.userId = userId;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void run() {
|
||||
String userName = userRepository.getUserNameForUserId(userId);
|
||||
userContextPerUserId.put(userId, new Context(userName));
|
||||
}
|
||||
}
|
||||
+24
@@ -0,0 +1,24 @@
|
||||
package com.baeldung.threadlocal;
|
||||
|
||||
import org.slf4j.Logger;
|
||||
import org.slf4j.LoggerFactory;
|
||||
|
||||
public class ThreadLocalWithUserContext implements Runnable {
|
||||
private static final Logger LOG = LoggerFactory.getLogger(ThreadLocalWithUserContext.class);
|
||||
|
||||
private static final ThreadLocal<Context> userContext = new ThreadLocal<>();
|
||||
private final Integer userId;
|
||||
private UserRepository userRepository = new UserRepository();
|
||||
|
||||
public ThreadLocalWithUserContext(Integer userId) {
|
||||
this.userId = userId;
|
||||
}
|
||||
|
||||
|
||||
@Override
|
||||
public void run() {
|
||||
String userName = userRepository.getUserNameForUserId(userId);
|
||||
userContext.set(new Context(userName));
|
||||
LOG.debug("thread context for given userId: " + userId + " is: " + userContext.get());
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,10 @@
|
||||
package com.baeldung.threadlocal;
|
||||
|
||||
import java.util.UUID;
|
||||
|
||||
|
||||
public class UserRepository {
|
||||
public String getUserNameForUserId(Integer userId) {
|
||||
return UUID.randomUUID().toString();
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,20 @@
|
||||
package com.baeldung.threadpool;
|
||||
|
||||
import java.util.concurrent.ForkJoinTask;
|
||||
import java.util.concurrent.RecursiveTask;
|
||||
import java.util.stream.Collectors;
|
||||
|
||||
public class CountingTask extends RecursiveTask<Integer> {
|
||||
|
||||
private final TreeNode node;
|
||||
|
||||
public CountingTask(TreeNode node) {
|
||||
this.node = node;
|
||||
}
|
||||
|
||||
@Override
|
||||
protected Integer compute() {
|
||||
return node.value + node.children.stream().map(childNode -> new CountingTask(childNode).fork()).collect(Collectors.summingInt(ForkJoinTask::join));
|
||||
}
|
||||
|
||||
}
|
||||
+29
@@ -0,0 +1,29 @@
|
||||
package com.baeldung.threadpool;
|
||||
|
||||
import java.util.concurrent.ExecutorService;
|
||||
import java.util.concurrent.Executors;
|
||||
import java.util.concurrent.ThreadPoolExecutor;
|
||||
import java.util.concurrent.TimeUnit;
|
||||
|
||||
import com.google.common.util.concurrent.MoreExecutors;
|
||||
|
||||
/**
|
||||
* This class demonstrates the usage of Guava's exiting executor services that keep the VM from hanging.
|
||||
* Without the exiting executor service, the task would hang indefinitely.
|
||||
* This behaviour cannot be demonstrated in JUnit tests, as JUnit kills the VM after the tests.
|
||||
*/
|
||||
public class ExitingExecutorServiceExample {
|
||||
|
||||
public static void main(String... args) {
|
||||
|
||||
final ThreadPoolExecutor executor = (ThreadPoolExecutor) Executors.newFixedThreadPool(5);
|
||||
final ExecutorService executorService = MoreExecutors.getExitingExecutorService(executor, 100, TimeUnit.MILLISECONDS);
|
||||
|
||||
executorService.submit((Runnable) () -> {
|
||||
while (true) {
|
||||
}
|
||||
});
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
@@ -0,0 +1,18 @@
|
||||
package com.baeldung.threadpool;
|
||||
|
||||
import java.util.Set;
|
||||
|
||||
import com.google.common.collect.Sets;
|
||||
|
||||
public class TreeNode {
|
||||
|
||||
int value;
|
||||
|
||||
Set<TreeNode> children;
|
||||
|
||||
public TreeNode(int value, TreeNode... children) {
|
||||
this.value = value;
|
||||
this.children = Sets.newHashSet(children);
|
||||
}
|
||||
|
||||
}
|
||||
@@ -0,0 +1,41 @@
|
||||
package com.baeldung.transferqueue;
|
||||
|
||||
import org.slf4j.Logger;
|
||||
import org.slf4j.LoggerFactory;
|
||||
|
||||
import java.util.concurrent.TransferQueue;
|
||||
import java.util.concurrent.atomic.AtomicInteger;
|
||||
|
||||
public class Consumer implements Runnable {
|
||||
private static final Logger LOG = LoggerFactory.getLogger(Consumer.class);
|
||||
|
||||
private final TransferQueue<String> transferQueue;
|
||||
private final String name;
|
||||
private final int numberOfMessagesToConsume;
|
||||
public final AtomicInteger numberOfConsumedMessages = new AtomicInteger();
|
||||
|
||||
public Consumer(TransferQueue<String> transferQueue, String name, int numberOfMessagesToConsume) {
|
||||
this.transferQueue = transferQueue;
|
||||
this.name = name;
|
||||
this.numberOfMessagesToConsume = numberOfMessagesToConsume;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void run() {
|
||||
for (int i = 0; i < numberOfMessagesToConsume; i++) {
|
||||
try {
|
||||
LOG.debug("Consumer: " + name + " is waiting to take element...");
|
||||
String element = transferQueue.take();
|
||||
longProcessing(element);
|
||||
LOG.debug("Consumer: " + name + " received element: " + element);
|
||||
} catch (InterruptedException e) {
|
||||
e.printStackTrace();
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
private void longProcessing(String element) throws InterruptedException {
|
||||
numberOfConsumedMessages.incrementAndGet();
|
||||
Thread.sleep(500);
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,41 @@
|
||||
package com.baeldung.transferqueue;
|
||||
|
||||
import org.slf4j.Logger;
|
||||
import org.slf4j.LoggerFactory;
|
||||
|
||||
import java.util.concurrent.TimeUnit;
|
||||
import java.util.concurrent.TransferQueue;
|
||||
import java.util.concurrent.atomic.AtomicInteger;
|
||||
|
||||
public class Producer implements Runnable {
|
||||
private static final Logger LOG = LoggerFactory.getLogger(Producer.class);
|
||||
|
||||
private final TransferQueue<String> transferQueue;
|
||||
private final String name;
|
||||
private final Integer numberOfMessagesToProduce;
|
||||
public final AtomicInteger numberOfProducedMessages = new AtomicInteger();
|
||||
|
||||
public Producer(TransferQueue<String> transferQueue, String name, Integer numberOfMessagesToProduce) {
|
||||
this.transferQueue = transferQueue;
|
||||
this.name = name;
|
||||
this.numberOfMessagesToProduce = numberOfMessagesToProduce;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void run() {
|
||||
for (int i = 0; i < numberOfMessagesToProduce; i++) {
|
||||
try {
|
||||
LOG.debug("Producer: " + name + " is waiting to transfer...");
|
||||
boolean added = transferQueue.tryTransfer("A" + i, 4000, TimeUnit.MILLISECONDS);
|
||||
if (added) {
|
||||
numberOfProducedMessages.incrementAndGet();
|
||||
LOG.debug("Producer: " + name + " transferred element: A" + i);
|
||||
} else {
|
||||
LOG.debug("can not add an element due to the timeout");
|
||||
}
|
||||
} catch (InterruptedException e) {
|
||||
e.printStackTrace();
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,9 @@
|
||||
# Set root logger level to DEBUG and its only appender to A1.
|
||||
log4j.rootLogger=DEBUG, A1
|
||||
|
||||
# A1 is set to be a ConsoleAppender.
|
||||
log4j.appender.A1=org.apache.log4j.ConsoleAppender
|
||||
|
||||
# A1 uses PatternLayout.
|
||||
log4j.appender.A1.layout=org.apache.log4j.PatternLayout
|
||||
log4j.appender.A1.layout.ConversionPattern=%-4r [%t] %-5p %c %x - %m%n
|
||||
@@ -0,0 +1,453 @@
|
||||
#
|
||||
# OWASP Enterprise Security API (ESAPI) Properties file -- PRODUCTION Version
|
||||
#
|
||||
# This file is part of the Open Web Application Security Project (OWASP)
|
||||
# Enterprise Security API (ESAPI) project. For details, please see
|
||||
# http://www.owasp.org/index.php/ESAPI.
|
||||
#
|
||||
# Copyright (c) 2008,2009 - The OWASP Foundation
|
||||
#
|
||||
# DISCUSS: This may cause a major backwards compatibility issue, etc. but
|
||||
# from a name space perspective, we probably should have prefaced
|
||||
# all the property names with ESAPI or at least OWASP. Otherwise
|
||||
# there could be problems is someone loads this properties file into
|
||||
# the System properties. We could also put this file into the
|
||||
# esapi.jar file (perhaps as a ResourceBundle) and then allow an external
|
||||
# ESAPI properties be defined that would overwrite these defaults.
|
||||
# That keeps the application's properties relatively simple as usually
|
||||
# they will only want to override a few properties. If looks like we
|
||||
# already support multiple override levels of this in the
|
||||
# DefaultSecurityConfiguration class, but I'm suggesting placing the
|
||||
# defaults in the esapi.jar itself. That way, if the jar is signed,
|
||||
# we could detect if those properties had been tampered with. (The
|
||||
# code to check the jar signatures is pretty simple... maybe 70-90 LOC,
|
||||
# but off course there is an execution penalty (similar to the way
|
||||
# that the separate sunjce.jar used to be when a class from it was
|
||||
# first loaded). Thoughts?
|
||||
###############################################################################
|
||||
#
|
||||
# WARNING: Operating system protection should be used to lock down the .esapi
|
||||
# resources directory and all the files inside and all the directories all the
|
||||
# way up to the root directory of the file system. Note that if you are using
|
||||
# file-based implementations, that some files may need to be read-write as they
|
||||
# get updated dynamically.
|
||||
#
|
||||
# Before using, be sure to update the MasterKey and MasterSalt as described below.
|
||||
# N.B.: If you had stored data that you have previously encrypted with ESAPI 1.4,
|
||||
# you *must* FIRST decrypt it using ESAPI 1.4 and then (if so desired)
|
||||
# re-encrypt it with ESAPI 2.0. If you fail to do this, you will NOT be
|
||||
# able to decrypt your data with ESAPI 2.0.
|
||||
#
|
||||
# YOU HAVE BEEN WARNED!!! More details are in the ESAPI 2.0 Release Notes.
|
||||
#
|
||||
#===========================================================================
|
||||
# ESAPI Configuration
|
||||
#
|
||||
# If true, then print all the ESAPI properties set here when they are loaded.
|
||||
# If false, they are not printed. Useful to reduce output when running JUnit tests.
|
||||
# If you need to troubleshoot a properties related problem, turning this on may help.
|
||||
# This is 'false' in the src/test/resources/.esapi version. It is 'true' by
|
||||
# default for reasons of backward compatibility with earlier ESAPI versions.
|
||||
ESAPI.printProperties=true
|
||||
|
||||
# ESAPI is designed to be easily extensible. You can use the reference implementation
|
||||
# or implement your own providers to take advantage of your enterprise's security
|
||||
# infrastructure. The functions in ESAPI are referenced using the ESAPI locator, like:
|
||||
#
|
||||
# String ciphertext =
|
||||
# ESAPI.encryptor().encrypt("Secret message"); // Deprecated in 2.0
|
||||
# CipherText cipherText =
|
||||
# ESAPI.encryptor().encrypt(new PlainText("Secret message")); // Preferred
|
||||
#
|
||||
# Below you can specify the classname for the provider that you wish to use in your
|
||||
# application. The only requirement is that it implement the appropriate ESAPI interface.
|
||||
# This allows you to switch security implementations in the future without rewriting the
|
||||
# entire application.
|
||||
#
|
||||
# ExperimentalAccessController requires ESAPI-AccessControlPolicy.xml in .esapi directory
|
||||
ESAPI.AccessControl=org.owasp.esapi.reference.DefaultAccessController
|
||||
# FileBasedAuthenticator requires users.txt file in .esapi directory
|
||||
ESAPI.Authenticator=org.owasp.esapi.reference.FileBasedAuthenticator
|
||||
ESAPI.Encoder=org.owasp.esapi.reference.DefaultEncoder
|
||||
ESAPI.Encryptor=org.owasp.esapi.reference.crypto.JavaEncryptor
|
||||
|
||||
ESAPI.Executor=org.owasp.esapi.reference.DefaultExecutor
|
||||
ESAPI.HTTPUtilities=org.owasp.esapi.reference.DefaultHTTPUtilities
|
||||
ESAPI.IntrusionDetector=org.owasp.esapi.reference.DefaultIntrusionDetector
|
||||
# Log4JFactory Requires log4j.xml or log4j.properties in classpath - http://www.laliluna.de/log4j-tutorial.html
|
||||
ESAPI.Logger=org.owasp.esapi.reference.Log4JLogFactory
|
||||
#ESAPI.Logger=org.owasp.esapi.reference.JavaLogFactory
|
||||
ESAPI.Randomizer=org.owasp.esapi.reference.DefaultRandomizer
|
||||
ESAPI.Validator=org.owasp.esapi.reference.DefaultValidator
|
||||
|
||||
#===========================================================================
|
||||
# ESAPI Authenticator
|
||||
#
|
||||
Authenticator.AllowedLoginAttempts=3
|
||||
Authenticator.MaxOldPasswordHashes=13
|
||||
Authenticator.UsernameParameterName=username
|
||||
Authenticator.PasswordParameterName=password
|
||||
# RememberTokenDuration (in days)
|
||||
Authenticator.RememberTokenDuration=14
|
||||
# Session Timeouts (in minutes)
|
||||
Authenticator.IdleTimeoutDuration=20
|
||||
Authenticator.AbsoluteTimeoutDuration=120
|
||||
|
||||
#===========================================================================
|
||||
# ESAPI Encoder
|
||||
#
|
||||
# ESAPI canonicalizes input before validation to prevent bypassing filters with encoded attacks.
|
||||
# Failure to canonicalize input is a very common mistake when implementing validation schemes.
|
||||
# Canonicalization is automatic when using the ESAPI Validator, but you can also use the
|
||||
# following code to canonicalize data.
|
||||
#
|
||||
# ESAPI.Encoder().canonicalize( "%22hello world"" );
|
||||
#
|
||||
# Multiple encoding is when a single encoding format is applied multiple times. Allowing
|
||||
# multiple encoding is strongly discouraged.
|
||||
Encoder.AllowMultipleEncoding=false
|
||||
|
||||
# Mixed encoding is when multiple different encoding formats are applied, or when
|
||||
# multiple formats are nested. Allowing multiple encoding is strongly discouraged.
|
||||
Encoder.AllowMixedEncoding=false
|
||||
|
||||
# The default list of codecs to apply when canonicalizing untrusted data. The list should include the codecs
|
||||
# for all downstream interpreters or decoders. For example, if the data is likely to end up in a URL, HTML, or
|
||||
# inside JavaScript, then the list of codecs below is appropriate. The order of the list is not terribly important.
|
||||
Encoder.DefaultCodecList=HTMLEntityCodec,PercentCodec,JavaScriptCodec
|
||||
|
||||
|
||||
#===========================================================================
|
||||
# ESAPI Encryption
|
||||
#
|
||||
# The ESAPI Encryptor provides basic cryptographic functions with a simplified API.
|
||||
# To get started, generate a new key using java -classpath esapi.jar org.owasp.esapi.reference.crypto.JavaEncryptor
|
||||
# There is not currently any support for key rotation, so be careful when changing your key and salt as it
|
||||
# will invalidate all signed, encrypted, and hashed data.
|
||||
#
|
||||
# WARNING: Not all combinations of algorithms and key lengths are supported.
|
||||
# If you choose to use a key length greater than 128, you MUST download the
|
||||
# unlimited strength policy files and install in the lib directory of your JRE/JDK.
|
||||
# See http://java.sun.com/javase/downloads/index.jsp for more information.
|
||||
#
|
||||
# Backward compatibility with ESAPI Java 1.4 is supported by the two deprecated API
|
||||
# methods, Encryptor.encrypt(String) and Encryptor.decrypt(String). However, whenever
|
||||
# possible, these methods should be avoided as they use ECB cipher mode, which in almost
|
||||
# all circumstances a poor choice because of it's weakness. CBC cipher mode is the default
|
||||
# for the new Encryptor encrypt / decrypt methods for ESAPI Java 2.0. In general, you
|
||||
# should only use this compatibility setting if you have persistent data encrypted with
|
||||
# version 1.4 and even then, you should ONLY set this compatibility mode UNTIL
|
||||
# you have decrypted all of your old encrypted data and then re-encrypted it with
|
||||
# ESAPI 2.0 using CBC mode. If you have some reason to mix the deprecated 1.4 mode
|
||||
# with the new 2.0 methods, make sure that you use the same cipher algorithm for both
|
||||
# (256-bit AES was the default for 1.4; 128-bit is the default for 2.0; see below for
|
||||
# more details.) Otherwise, you will have to use the new 2.0 encrypt / decrypt methods
|
||||
# where you can specify a SecretKey. (Note that if you are using the 256-bit AES,
|
||||
# that requires downloading the special jurisdiction policy files mentioned above.)
|
||||
#
|
||||
# ***** IMPORTANT: Do NOT forget to replace these with your own values! *****
|
||||
# To calculate these values, you can run:
|
||||
# java -classpath esapi.jar org.owasp.esapi.reference.crypto.JavaEncryptor
|
||||
#
|
||||
Encryptor.MasterKey=tzfztf56ftv
|
||||
Encryptor.MasterSalt=123456ztrewq
|
||||
|
||||
# Provides the default JCE provider that ESAPI will "prefer" for its symmetric
|
||||
# encryption and hashing. (That is it will look to this provider first, but it
|
||||
# will defer to other providers if the requested algorithm is not implemented
|
||||
# by this provider.) If left unset, ESAPI will just use your Java VM's current
|
||||
# preferred JCE provider, which is generally set in the file
|
||||
# "$JAVA_HOME/jre/lib/security/java.security".
|
||||
#
|
||||
# The main intent of this is to allow ESAPI symmetric encryption to be
|
||||
# used with a FIPS 140-2 compliant crypto-module. For details, see the section
|
||||
# "Using ESAPI Symmetric Encryption with FIPS 140-2 Cryptographic Modules" in
|
||||
# the ESAPI 2.0 Symmetric Encryption User Guide, at:
|
||||
# http://owasp-esapi-java.googlecode.com/svn/trunk/documentation/esapi4java-core-2.0-symmetric-crypto-user-guide.html
|
||||
# However, this property also allows you to easily use an alternate JCE provider
|
||||
# such as "Bouncy Castle" without having to make changes to "java.security".
|
||||
# See Javadoc for SecurityProviderLoader for further details. If you wish to use
|
||||
# a provider that is not known to SecurityProviderLoader, you may specify the
|
||||
# fully-qualified class name of the JCE provider class that implements
|
||||
# java.security.Provider. If the name contains a '.', this is interpreted as
|
||||
# a fully-qualified class name that implements java.security.Provider.
|
||||
#
|
||||
# NOTE: Setting this property has the side-effect of changing it in your application
|
||||
# as well, so if you are using JCE in your application directly rather than
|
||||
# through ESAPI (you wouldn't do that, would you? ;-), it will change the
|
||||
# preferred JCE provider there as well.
|
||||
#
|
||||
# Default: Keeps the JCE provider set to whatever JVM sets it to.
|
||||
Encryptor.PreferredJCEProvider=
|
||||
|
||||
# AES is the most widely used and strongest encryption algorithm. This
|
||||
# should agree with your Encryptor.CipherTransformation property.
|
||||
# By default, ESAPI Java 1.4 uses "PBEWithMD5AndDES" and which is
|
||||
# very weak. It is essentially a password-based encryption key, hashed
|
||||
# with MD5 around 1K times and then encrypted with the weak DES algorithm
|
||||
# (56-bits) using ECB mode and an unspecified padding (it is
|
||||
# JCE provider specific, but most likely "NoPadding"). However, 2.0 uses
|
||||
# "AES/CBC/PKCSPadding". If you want to change these, change them here.
|
||||
# Warning: This property does not control the default reference implementation for
|
||||
# ESAPI 2.0 using JavaEncryptor. Also, this property will be dropped
|
||||
# in the future.
|
||||
# @deprecated
|
||||
Encryptor.EncryptionAlgorithm=AES
|
||||
# For ESAPI Java 2.0 - New encrypt / decrypt methods use this.
|
||||
Encryptor.CipherTransformation=AES/CBC/PKCS5Padding
|
||||
|
||||
# Applies to ESAPI 2.0 and later only!
|
||||
# Comma-separated list of cipher modes that provide *BOTH*
|
||||
# confidentiality *AND* message authenticity. (NIST refers to such cipher
|
||||
# modes as "combined modes" so that's what we shall call them.) If any of these
|
||||
# cipher modes are used then no MAC is calculated and stored
|
||||
# in the CipherText upon encryption. Likewise, if one of these
|
||||
# cipher modes is used with decryption, no attempt will be made
|
||||
# to validate the MAC contained in the CipherText object regardless
|
||||
# of whether it contains one or not. Since the expectation is that
|
||||
# these cipher modes support support message authenticity already,
|
||||
# injecting a MAC in the CipherText object would be at best redundant.
|
||||
#
|
||||
# Note that as of JDK 1.5, the SunJCE provider does not support *any*
|
||||
# of these cipher modes. Of these listed, only GCM and CCM are currently
|
||||
# NIST approved. YMMV for other JCE providers. E.g., Bouncy Castle supports
|
||||
# GCM and CCM with "NoPadding" mode, but not with "PKCS5Padding" or other
|
||||
# padding modes.
|
||||
Encryptor.cipher_modes.combined_modes=GCM,CCM,IAPM,EAX,OCB,CWC
|
||||
|
||||
# Applies to ESAPI 2.0 and later only!
|
||||
# Additional cipher modes allowed for ESAPI 2.0 encryption. These
|
||||
# cipher modes are in _addition_ to those specified by the property
|
||||
# 'Encryptor.cipher_modes.combined_modes'.
|
||||
# Note: We will add support for streaming modes like CFB & OFB once
|
||||
# we add support for 'specified' to the property 'Encryptor.ChooseIVMethod'
|
||||
# (probably in ESAPI 2.1).
|
||||
# DISCUSS: Better name?
|
||||
Encryptor.cipher_modes.additional_allowed=CBC
|
||||
|
||||
# 128-bit is almost always sufficient and appears to be more resistant to
|
||||
# related key attacks than is 256-bit AES. Use '_' to use default key size
|
||||
# for cipher algorithms (where it makes sense because the algorithm supports
|
||||
# a variable key size). Key length must agree to what's provided as the
|
||||
# cipher transformation, otherwise this will be ignored after logging a
|
||||
# warning.
|
||||
#
|
||||
# NOTE: This is what applies BOTH ESAPI 1.4 and 2.0. See warning above about mixing!
|
||||
Encryptor.EncryptionKeyLength=128
|
||||
|
||||
# Because 2.0 uses CBC mode by default, it requires an initialization vector (IV).
|
||||
# (All cipher modes except ECB require an IV.) There are two choices: we can either
|
||||
# use a fixed IV known to both parties or allow ESAPI to choose a random IV. While
|
||||
# the IV does not need to be hidden from adversaries, it is important that the
|
||||
# adversary not be allowed to choose it. Also, random IVs are generally much more
|
||||
# secure than fixed IVs. (In fact, it is essential that feed-back cipher modes
|
||||
# such as CFB and OFB use a different IV for each encryption with a given key so
|
||||
# in such cases, random IVs are much preferred. By default, ESAPI 2.0 uses random
|
||||
# IVs. If you wish to use 'fixed' IVs, set 'Encryptor.ChooseIVMethod=fixed' and
|
||||
# uncomment the Encryptor.fixedIV.
|
||||
#
|
||||
# Valid values: random|fixed|specified 'specified' not yet implemented; planned for 2.1
|
||||
Encryptor.ChooseIVMethod=random
|
||||
# If you choose to use a fixed IV, then you must place a fixed IV here that
|
||||
# is known to all others who are sharing your secret key. The format should
|
||||
# be a hex string that is the same length as the cipher block size for the
|
||||
# cipher algorithm that you are using. The following is an *example* for AES
|
||||
# from an AES test vector for AES-128/CBC as described in:
|
||||
# NIST Special Publication 800-38A (2001 Edition)
|
||||
# "Recommendation for Block Cipher Modes of Operation".
|
||||
# (Note that the block size for AES is 16 bytes == 128 bits.)
|
||||
#
|
||||
Encryptor.fixedIV=0x000102030405060708090a0b0c0d0e0f
|
||||
|
||||
# Whether or not CipherText should use a message authentication code (MAC) with it.
|
||||
# This prevents an adversary from altering the IV as well as allowing a more
|
||||
# fool-proof way of determining the decryption failed because of an incorrect
|
||||
# key being supplied. This refers to the "separate" MAC calculated and stored
|
||||
# in CipherText, not part of any MAC that is calculated as a result of a
|
||||
# "combined mode" cipher mode.
|
||||
#
|
||||
# If you are using ESAPI with a FIPS 140-2 cryptographic module, you *must* also
|
||||
# set this property to false.
|
||||
Encryptor.CipherText.useMAC=true
|
||||
|
||||
# Whether or not the PlainText object may be overwritten and then marked
|
||||
# eligible for garbage collection. If not set, this is still treated as 'true'.
|
||||
Encryptor.PlainText.overwrite=true
|
||||
|
||||
# Do not use DES except in a legacy situations. 56-bit is way too small key size.
|
||||
#Encryptor.EncryptionKeyLength=56
|
||||
#Encryptor.EncryptionAlgorithm=DES
|
||||
|
||||
# TripleDES is considered strong enough for most purposes.
|
||||
# Note: There is also a 112-bit version of DESede. Using the 168-bit version
|
||||
# requires downloading the special jurisdiction policy from Sun.
|
||||
#Encryptor.EncryptionKeyLength=168
|
||||
#Encryptor.EncryptionAlgorithm=DESede
|
||||
|
||||
Encryptor.HashAlgorithm=SHA-512
|
||||
Encryptor.HashIterations=1024
|
||||
Encryptor.DigitalSignatureAlgorithm=SHA1withDSA
|
||||
Encryptor.DigitalSignatureKeyLength=1024
|
||||
Encryptor.RandomAlgorithm=SHA1PRNG
|
||||
Encryptor.CharacterEncoding=UTF-8
|
||||
|
||||
# This is the Pseudo Random Function (PRF) that ESAPI's Key Derivation Function
|
||||
# (KDF) normally uses. Note this is *only* the PRF used for ESAPI's KDF and
|
||||
# *not* what is used for ESAPI's MAC. (Currently, HmacSHA1 is always used for
|
||||
# the MAC, mostly to keep the overall size at a minimum.)
|
||||
#
|
||||
# Currently supported choices for JDK 1.5 and 1.6 are:
|
||||
# HmacSHA1 (160 bits), HmacSHA256 (256 bits), HmacSHA384 (384 bits), and
|
||||
# HmacSHA512 (512 bits).
|
||||
# Note that HmacMD5 is *not* supported for the PRF used by the KDF even though
|
||||
# the JDKs support it. See the ESAPI 2.0 Symmetric Encryption User Guide
|
||||
# further details.
|
||||
Encryptor.KDF.PRF=HmacSHA256
|
||||
#===========================================================================
|
||||
# ESAPI HttpUtilties
|
||||
#
|
||||
# The HttpUtilities provide basic protections to HTTP requests and responses. Primarily these methods
|
||||
# protect against malicious data from attackers, such as unprintable characters, escaped characters,
|
||||
# and other simple attacks. The HttpUtilities also provides utility methods for dealing with cookies,
|
||||
# headers, and CSRF tokens.
|
||||
#
|
||||
# Default file upload location (remember to escape backslashes with \\)
|
||||
HttpUtilities.UploadDir=C:\\ESAPI\\testUpload
|
||||
HttpUtilities.UploadTempDir=C:\\temp
|
||||
# Force flags on cookies, if you use HttpUtilities to set cookies
|
||||
HttpUtilities.ForceHttpOnlySession=false
|
||||
HttpUtilities.ForceSecureSession=false
|
||||
HttpUtilities.ForceHttpOnlyCookies=true
|
||||
HttpUtilities.ForceSecureCookies=true
|
||||
# Maximum size of HTTP headers
|
||||
HttpUtilities.MaxHeaderSize=4096
|
||||
# File upload configuration
|
||||
HttpUtilities.ApprovedUploadExtensions=.zip,.pdf,.doc,.docx,.ppt,.pptx,.tar,.gz,.tgz,.rar,.war,.jar,.ear,.xls,.rtf,.properties,.java,.class,.txt,.xml,.jsp,.jsf,.exe,.dll
|
||||
HttpUtilities.MaxUploadFileBytes=500000000
|
||||
# Using UTF-8 throughout your stack is highly recommended. That includes your database driver,
|
||||
# container, and any other technologies you may be using. Failure to do this may expose you
|
||||
# to Unicode transcoding injection attacks. Use of UTF-8 does not hinder internationalization.
|
||||
HttpUtilities.ResponseContentType=text/html; charset=UTF-8
|
||||
# This is the name of the cookie used to represent the HTTP session
|
||||
# Typically this will be the default "JSESSIONID"
|
||||
HttpUtilities.HttpSessionIdName=JSESSIONID
|
||||
|
||||
|
||||
|
||||
#===========================================================================
|
||||
# ESAPI Executor
|
||||
# CHECKME - Not sure what this is used for, but surely it should be made OS independent.
|
||||
Executor.WorkingDirectory=C:\\Windows\\Temp
|
||||
Executor.ApprovedExecutables=C:\\Windows\\System32\\cmd.exe,C:\\Windows\\System32\\runas.exe
|
||||
|
||||
|
||||
#===========================================================================
|
||||
# ESAPI Logging
|
||||
# Set the application name if these logs are combined with other applications
|
||||
Logger.ApplicationName=ExampleApplication
|
||||
# If you use an HTML log viewer that does not properly HTML escape log data, you can set LogEncodingRequired to true
|
||||
Logger.LogEncodingRequired=false
|
||||
# Determines whether ESAPI should log the application name. This might be clutter in some single-server/single-app environments.
|
||||
Logger.LogApplicationName=true
|
||||
# Determines whether ESAPI should log the server IP and port. This might be clutter in some single-server environments.
|
||||
Logger.LogServerIP=true
|
||||
# LogFileName, the name of the logging file. Provide a full directory path (e.g., C:\\ESAPI\\ESAPI_logging_file) if you
|
||||
# want to place it in a specific directory.
|
||||
Logger.LogFileName=ESAPI_logging_file
|
||||
# MaxLogFileSize, the max size (in bytes) of a single log file before it cuts over to a new one (default is 10,000,000)
|
||||
Logger.MaxLogFileSize=10000000
|
||||
|
||||
|
||||
#===========================================================================
|
||||
# ESAPI Intrusion Detection
|
||||
#
|
||||
# Each event has a base to which .count, .interval, and .action are added
|
||||
# The IntrusionException will fire if we receive "count" events within "interval" seconds
|
||||
# The IntrusionDetector is configurable to take the following actions: log, logout, and disable
|
||||
# (multiple actions separated by commas are allowed e.g. event.test.actions=log,disable
|
||||
#
|
||||
# Custom Events
|
||||
# Names must start with "event." as the base
|
||||
# Use IntrusionDetector.addEvent( "test" ) in your code to trigger "event.test" here
|
||||
# You can also disable intrusion detection completely by changing
|
||||
# the following parameter to true
|
||||
#
|
||||
IntrusionDetector.Disable=false
|
||||
#
|
||||
IntrusionDetector.event.test.count=2
|
||||
IntrusionDetector.event.test.interval=10
|
||||
IntrusionDetector.event.test.actions=disable,log
|
||||
|
||||
# Exception Events
|
||||
# All EnterpriseSecurityExceptions are registered automatically
|
||||
# Call IntrusionDetector.getInstance().addException(e) for Exceptions that do not extend EnterpriseSecurityException
|
||||
# Use the fully qualified classname of the exception as the base
|
||||
|
||||
# any intrusion is an attack
|
||||
IntrusionDetector.org.owasp.esapi.errors.IntrusionException.count=1
|
||||
IntrusionDetector.org.owasp.esapi.errors.IntrusionException.interval=1
|
||||
IntrusionDetector.org.owasp.esapi.errors.IntrusionException.actions=log,disable,logout
|
||||
|
||||
# for test purposes
|
||||
# CHECKME: Shouldn't there be something in the property name itself that designates
|
||||
# that these are for testing???
|
||||
IntrusionDetector.org.owasp.esapi.errors.IntegrityException.count=10
|
||||
IntrusionDetector.org.owasp.esapi.errors.IntegrityException.interval=5
|
||||
IntrusionDetector.org.owasp.esapi.errors.IntegrityException.actions=log,disable,logout
|
||||
|
||||
# rapid validation errors indicate scans or attacks in progress
|
||||
# org.owasp.esapi.errors.ValidationException.count=10
|
||||
# org.owasp.esapi.errors.ValidationException.interval=10
|
||||
# org.owasp.esapi.errors.ValidationException.actions=log,logout
|
||||
|
||||
# sessions jumping between hosts indicates session hijacking
|
||||
IntrusionDetector.org.owasp.esapi.errors.AuthenticationHostException.count=2
|
||||
IntrusionDetector.org.owasp.esapi.errors.AuthenticationHostException.interval=10
|
||||
IntrusionDetector.org.owasp.esapi.errors.AuthenticationHostException.actions=log,logout
|
||||
|
||||
|
||||
#===========================================================================
|
||||
# ESAPI Validation
|
||||
#
|
||||
# The ESAPI Validator works on regular expressions with defined names. You can define names
|
||||
# either here, or you may define application specific patterns in a separate file defined below.
|
||||
# This allows enterprises to specify both organizational standards as well as application specific
|
||||
# validation rules.
|
||||
#
|
||||
Validator.ConfigurationFile=validation.properties
|
||||
|
||||
# Validators used by ESAPI
|
||||
Validator.AccountName=^[a-zA-Z0-9]{3,20}$
|
||||
Validator.SystemCommand=^[a-zA-Z\\-\\/]{1,64}$
|
||||
Validator.RoleName=^[a-z]{1,20}$
|
||||
|
||||
#the word TEST below should be changed to your application
|
||||
#name - only relative URL's are supported
|
||||
Validator.Redirect=^\\/test.*$
|
||||
|
||||
# Global HTTP Validation Rules
|
||||
# Values with Base64 encoded data (e.g. encrypted state) will need at least [a-zA-Z0-9\/+=]
|
||||
Validator.HTTPScheme=^(http|https)$
|
||||
Validator.HTTPServerName=^[a-zA-Z0-9_.\\-]*$
|
||||
Validator.HTTPParameterName=^[a-zA-Z0-9_]{1,32}$
|
||||
Validator.HTTPParameterValue=^[a-zA-Z0-9.\\-\\/+=@_ ]*$
|
||||
Validator.HTTPCookieName=^[a-zA-Z0-9\\-_]{1,32}$
|
||||
Validator.HTTPCookieValue=^[a-zA-Z0-9\\-\\/+=_ ]*$
|
||||
Validator.HTTPHeaderName=^[a-zA-Z0-9\\-_]{1,32}$
|
||||
Validator.HTTPHeaderValue=^[a-zA-Z0-9()\\-=\\*\\.\\?;,+\\/:&_ ]*$
|
||||
Validator.HTTPContextPath=^\\/?[a-zA-Z0-9.\\-\\/_]*$
|
||||
Validator.HTTPServletPath=^[a-zA-Z0-9.\\-\\/_]*$
|
||||
Validator.HTTPPath=^[a-zA-Z0-9.\\-_]*$
|
||||
Validator.HTTPQueryString=^[a-zA-Z0-9()\\-=\\*\\.\\?;,+\\/:&_ %]*$
|
||||
Validator.HTTPURI=^[a-zA-Z0-9()\\-=\\*\\.\\?;,+\\/:&_ ]*$
|
||||
Validator.HTTPURL=^.*$
|
||||
Validator.HTTPJSESSIONID=^[A-Z0-9]{10,30}$
|
||||
|
||||
# Validation of file related input
|
||||
Validator.FileName=^[a-zA-Z0-9!@#$%^&{}\\[\\]()_+\\-=,.~'` ]{1,255}$
|
||||
Validator.DirectoryName=^[a-zA-Z0-9:/\\\\!@#$%^&{}\\[\\]()_+\\-=,.~'` ]{1,255}$
|
||||
|
||||
# Validation of dates. Controls whether or not 'lenient' dates are accepted.
|
||||
# See DataFormat.setLenient(boolean flag) for further details.
|
||||
Validator.AcceptLenientDates=false
|
||||
|
||||
@@ -0,0 +1,20 @@
|
||||
<?xml version="1.0" encoding="UTF-8" ?>
|
||||
<persistence xmlns="http://xmlns.jcp.org/xml/ns/persistence"
|
||||
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
|
||||
xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence
|
||||
http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd" version="2.1">
|
||||
|
||||
<!-- JDO tutorial "unit" -->
|
||||
<persistence-unit name="Tutorial">
|
||||
<exclude-unlisted-classes/>
|
||||
<properties>
|
||||
<property name="javax.jdo.PersistenceManagerFactoryClass" value="org.datanucleus.api.jdo.JDOPersistenceManagerFactory"/>
|
||||
<property name="javax.jdo.option.ConnectionURL" value="jdbc:h2:mem:mypersistence"/>
|
||||
<property name="javax.jdo.option.ConnectionDriverName" value="org.h2.Driver"/>
|
||||
<property name="javax.jdo.option.ConnectionUserName" value="sa"/>
|
||||
<property name="javax.jdo.option.ConnectionPassword" value=""/>
|
||||
<property name="datanucleus.schema.autoCreateAll" value="true"/>
|
||||
</properties>
|
||||
</persistence-unit>
|
||||
</persistence>
|
||||
|
||||
@@ -0,0 +1,3 @@
|
||||
1|IND|India
|
||||
2|MY|Malaysia
|
||||
3|AU|Australia
|
||||
|
@@ -0,0 +1,6 @@
|
||||
dataSourceClassName=//TBD
|
||||
dataSource.user=//TBD
|
||||
dataSource.password=//TBD
|
||||
dataSource.databaseName=//TBD
|
||||
dataSource.portNumber=//TBD
|
||||
dataSource.serverName=//TBD
|
||||
Binary file not shown.
@@ -0,0 +1,15 @@
|
||||
var first = {
|
||||
name: "Whiskey",
|
||||
age: 5
|
||||
};
|
||||
|
||||
var second = {
|
||||
volume: 100
|
||||
};
|
||||
|
||||
Object.bindProperties(first, second);
|
||||
|
||||
print(first.volume);
|
||||
|
||||
second.volume = 1000;
|
||||
print(first.volume);
|
||||
@@ -0,0 +1 @@
|
||||
print(__FILE__, __LINE__, __DIR__);
|
||||
@@ -0,0 +1,19 @@
|
||||
var math = {
|
||||
increment: function (num) {
|
||||
return ++num;
|
||||
},
|
||||
|
||||
failFunc: function () {
|
||||
try {
|
||||
throw "BOOM";
|
||||
} catch (e if typeof e === 'string') {
|
||||
print("String thrown: " + e);
|
||||
}
|
||||
catch (e) {
|
||||
print("this shouldn't happen!");
|
||||
}
|
||||
}
|
||||
};
|
||||
|
||||
|
||||
math;
|
||||
@@ -0,0 +1,11 @@
|
||||
var demo = {
|
||||
__noSuchProperty__: function (propName) {
|
||||
print("Accessed non-existing property: " + propName);
|
||||
},
|
||||
|
||||
__noSuchMethod__: function (methodName) {
|
||||
print("Invoked non-existing method: " + methodName);
|
||||
}
|
||||
};
|
||||
|
||||
demo;
|
||||
@@ -0,0 +1 @@
|
||||
function increment(num) ++num;
|
||||
@@ -0,0 +1,2 @@
|
||||
print(" hello world".trimLeft());
|
||||
print("hello world ".trimRight());
|
||||
@@ -0,0 +1,9 @@
|
||||
function arrays(arr) {
|
||||
|
||||
var javaIntArray = Java.to(arr, "int[]");
|
||||
print(javaIntArray[0]);
|
||||
print(javaIntArray[1]);
|
||||
print(javaIntArray[2]);
|
||||
}
|
||||
|
||||
arrays([100, "1654", true]);
|
||||
@@ -0,0 +1,6 @@
|
||||
log4j.rootLogger=DEBUG, A1
|
||||
|
||||
log4j.appender.A1=org.apache.log4j.ConsoleAppender
|
||||
|
||||
log4j.appender.A1.layout=org.apache.log4j.PatternLayout
|
||||
log4j.appender.A1.layout.ConversionPattern=%-4r [%t] %-5p %c %x - %m%n
|
||||
@@ -0,0 +1,9 @@
|
||||
|
||||
# Root logger
|
||||
log4j.rootLogger=INFO, file, stdout
|
||||
|
||||
# Write to console
|
||||
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
|
||||
log4j.appender.stdout.Target=System.out
|
||||
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
|
||||
log4j.appender.stdout.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n
|
||||
@@ -0,0 +1,19 @@
|
||||
<?xml version="1.0" encoding="UTF-8"?>
|
||||
<configuration>
|
||||
<appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
|
||||
<encoder>
|
||||
<pattern>web - %date [%thread] %-5level %logger{36} - %message%n
|
||||
</pattern>
|
||||
</encoder>
|
||||
</appender>
|
||||
|
||||
<logger name="org.springframework" level="WARN" />
|
||||
<logger name="org.springframework.transaction" level="WARN" />
|
||||
|
||||
<!-- in order to debug some marshalling issues, this needs to be TRACE -->
|
||||
<logger name="org.springframework.web.servlet.mvc" level="WARN" />
|
||||
|
||||
<root level="INFO">
|
||||
<appender-ref ref="STDOUT" />
|
||||
</root>
|
||||
</configuration>
|
||||
Binary file not shown.
@@ -0,0 +1,2 @@
|
||||
line 1
|
||||
a second line
|
||||
+177
@@ -0,0 +1,177 @@
|
||||
package com.baeldung.completablefuture;
|
||||
|
||||
import org.junit.Test;
|
||||
import org.slf4j.Logger;
|
||||
import org.slf4j.LoggerFactory;
|
||||
|
||||
import java.util.concurrent.*;
|
||||
import java.util.stream.Collectors;
|
||||
import java.util.stream.Stream;
|
||||
|
||||
import static org.junit.Assert.assertEquals;
|
||||
import static org.junit.Assert.assertTrue;
|
||||
|
||||
public class CompletableFutureLongRunningUnitTest {
|
||||
|
||||
private static final Logger LOG = LoggerFactory.getLogger(CompletableFutureLongRunningUnitTest.class);
|
||||
|
||||
|
||||
@Test
|
||||
public void whenRunningCompletableFutureAsynchronously_thenGetMethodWaitsForResult() throws InterruptedException, ExecutionException {
|
||||
Future<String> completableFuture = calculateAsync();
|
||||
|
||||
String result = completableFuture.get();
|
||||
assertEquals("Hello", result);
|
||||
}
|
||||
|
||||
private Future<String> calculateAsync() throws InterruptedException {
|
||||
CompletableFuture<String> completableFuture = new CompletableFuture<>();
|
||||
|
||||
Executors.newCachedThreadPool().submit(() -> {
|
||||
Thread.sleep(500);
|
||||
completableFuture.complete("Hello");
|
||||
return null;
|
||||
});
|
||||
|
||||
return completableFuture;
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenRunningCompletableFutureWithResult_thenGetMethodReturnsImmediately() throws InterruptedException, ExecutionException {
|
||||
Future<String> completableFuture = CompletableFuture.completedFuture("Hello");
|
||||
|
||||
String result = completableFuture.get();
|
||||
assertEquals("Hello", result);
|
||||
}
|
||||
|
||||
private Future<String> calculateAsyncWithCancellation() throws InterruptedException {
|
||||
CompletableFuture<String> completableFuture = new CompletableFuture<>();
|
||||
|
||||
Executors.newCachedThreadPool().submit(() -> {
|
||||
Thread.sleep(500);
|
||||
completableFuture.cancel(false);
|
||||
return null;
|
||||
});
|
||||
|
||||
return completableFuture;
|
||||
}
|
||||
|
||||
@Test(expected = CancellationException.class)
|
||||
public void whenCancelingTheFuture_thenThrowsCancellationException() throws ExecutionException, InterruptedException {
|
||||
Future<String> future = calculateAsyncWithCancellation();
|
||||
future.get();
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenCreatingCompletableFutureWithSupplyAsync_thenFutureReturnsValue() throws ExecutionException, InterruptedException {
|
||||
CompletableFuture<String> future = CompletableFuture.supplyAsync(() -> "Hello");
|
||||
|
||||
assertEquals("Hello", future.get());
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenAddingThenAcceptToFuture_thenFunctionExecutesAfterComputationIsFinished() throws ExecutionException, InterruptedException {
|
||||
CompletableFuture<String> completableFuture = CompletableFuture.supplyAsync(() -> "Hello");
|
||||
|
||||
CompletableFuture<Void> future = completableFuture.thenAccept(s -> LOG.debug("Computation returned: " + s));
|
||||
|
||||
future.get();
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenAddingThenRunToFuture_thenFunctionExecutesAfterComputationIsFinished() throws ExecutionException, InterruptedException {
|
||||
CompletableFuture<String> completableFuture = CompletableFuture.supplyAsync(() -> "Hello");
|
||||
|
||||
CompletableFuture<Void> future = completableFuture.thenRun(() -> LOG.debug("Computation finished."));
|
||||
|
||||
future.get();
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenAddingThenApplyToFuture_thenFunctionExecutesAfterComputationIsFinished() throws ExecutionException, InterruptedException {
|
||||
CompletableFuture<String> completableFuture = CompletableFuture.supplyAsync(() -> "Hello");
|
||||
|
||||
CompletableFuture<String> future = completableFuture.thenApply(s -> s + " World");
|
||||
|
||||
assertEquals("Hello World", future.get());
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenUsingThenCompose_thenFuturesExecuteSequentially() throws ExecutionException, InterruptedException {
|
||||
CompletableFuture<String> completableFuture = CompletableFuture.supplyAsync(() -> "Hello").thenCompose(s -> CompletableFuture.supplyAsync(() -> s + " World"));
|
||||
|
||||
assertEquals("Hello World", completableFuture.get());
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenUsingThenCombine_thenWaitForExecutionOfBothFutures() throws ExecutionException, InterruptedException {
|
||||
CompletableFuture<String> completableFuture = CompletableFuture.supplyAsync(() -> "Hello").thenCombine(CompletableFuture.supplyAsync(() -> " World"), (s1, s2) -> s1 + s2);
|
||||
|
||||
assertEquals("Hello World", completableFuture.get());
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenUsingThenAcceptBoth_thenWaitForExecutionOfBothFutures() throws ExecutionException, InterruptedException {
|
||||
CompletableFuture.supplyAsync(() -> "Hello").thenAcceptBoth(CompletableFuture.supplyAsync(() -> " World"), (s1, s2) -> LOG.debug(s1 + s2));
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenFutureCombinedWithAllOfCompletes_thenAllFuturesAreDone() throws ExecutionException, InterruptedException {
|
||||
CompletableFuture<String> future1 = CompletableFuture.supplyAsync(() -> "Hello");
|
||||
CompletableFuture<String> future2 = CompletableFuture.supplyAsync(() -> "Beautiful");
|
||||
CompletableFuture<String> future3 = CompletableFuture.supplyAsync(() -> "World");
|
||||
|
||||
CompletableFuture<Void> combinedFuture = CompletableFuture.allOf(future1, future2, future3);
|
||||
|
||||
// ...
|
||||
|
||||
combinedFuture.get();
|
||||
|
||||
assertTrue(future1.isDone());
|
||||
assertTrue(future2.isDone());
|
||||
assertTrue(future3.isDone());
|
||||
|
||||
String combined = Stream.of(future1, future2, future3).map(CompletableFuture::join).collect(Collectors.joining(" "));
|
||||
|
||||
assertEquals("Hello Beautiful World", combined);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenFutureThrows_thenHandleMethodReceivesException() throws ExecutionException, InterruptedException {
|
||||
String name = null;
|
||||
|
||||
// ...
|
||||
|
||||
CompletableFuture<String> completableFuture = CompletableFuture.supplyAsync(() -> {
|
||||
if (name == null) {
|
||||
throw new RuntimeException("Computation error!");
|
||||
}
|
||||
return "Hello, " + name;
|
||||
}).handle((s, t) -> s != null ? s : "Hello, Stranger!");
|
||||
|
||||
assertEquals("Hello, Stranger!", completableFuture.get());
|
||||
}
|
||||
|
||||
@Test(expected = ExecutionException.class)
|
||||
public void whenCompletingFutureExceptionally_thenGetMethodThrows() throws ExecutionException, InterruptedException {
|
||||
CompletableFuture<String> completableFuture = new CompletableFuture<>();
|
||||
|
||||
// ...
|
||||
|
||||
completableFuture.completeExceptionally(new RuntimeException("Calculation failed!"));
|
||||
|
||||
// ...
|
||||
|
||||
completableFuture.get();
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenAddingThenApplyAsyncToFuture_thenFunctionExecutesAfterComputationIsFinished() throws ExecutionException, InterruptedException {
|
||||
CompletableFuture<String> completableFuture = CompletableFuture.supplyAsync(() -> "Hello");
|
||||
|
||||
CompletableFuture<String> future = completableFuture.thenApplyAsync(s -> s + " World");
|
||||
|
||||
assertEquals("Hello World", future.get());
|
||||
}
|
||||
|
||||
}
|
||||
+38
@@ -0,0 +1,38 @@
|
||||
package com.baeldung.concurrent.accumulator;
|
||||
|
||||
import org.junit.Test;
|
||||
|
||||
import java.util.concurrent.ExecutorService;
|
||||
import java.util.concurrent.Executors;
|
||||
import java.util.concurrent.TimeUnit;
|
||||
import java.util.concurrent.atomic.LongAccumulator;
|
||||
import java.util.function.LongBinaryOperator;
|
||||
import java.util.stream.IntStream;
|
||||
|
||||
import static junit.framework.TestCase.assertEquals;
|
||||
|
||||
public class LongAccumulatorUnitTest {
|
||||
|
||||
@Test
|
||||
public void givenLongAccumulator_whenApplyActionOnItFromMultipleThrads_thenShouldProduceProperResult() throws InterruptedException {
|
||||
// given
|
||||
ExecutorService executorService = Executors.newFixedThreadPool(8);
|
||||
LongBinaryOperator sum = Long::sum;
|
||||
LongAccumulator accumulator = new LongAccumulator(sum, 0L);
|
||||
int numberOfThreads = 4;
|
||||
int numberOfIncrements = 100;
|
||||
|
||||
// when
|
||||
Runnable accumulateAction = () -> IntStream.rangeClosed(0, numberOfIncrements).forEach(accumulator::accumulate);
|
||||
|
||||
for (int i = 0; i < numberOfThreads; i++) {
|
||||
executorService.execute(accumulateAction);
|
||||
}
|
||||
|
||||
// then
|
||||
executorService.awaitTermination(500, TimeUnit.MILLISECONDS);
|
||||
executorService.shutdown();
|
||||
assertEquals(accumulator.get(), 20200);
|
||||
|
||||
}
|
||||
}
|
||||
+67
@@ -0,0 +1,67 @@
|
||||
package com.baeldung.concurrent.adder;
|
||||
|
||||
import org.junit.Test;
|
||||
|
||||
import java.util.concurrent.ExecutorService;
|
||||
import java.util.concurrent.Executors;
|
||||
import java.util.concurrent.TimeUnit;
|
||||
import java.util.concurrent.atomic.LongAdder;
|
||||
import java.util.stream.IntStream;
|
||||
|
||||
import static com.jayway.awaitility.Awaitility.await;
|
||||
import static junit.framework.TestCase.assertEquals;
|
||||
|
||||
public class LongAdderUnitTest {
|
||||
@Test
|
||||
public void givenMultipleThread_whenTheyWriteToSharedLongAdder_thenShouldCalculateSumForThem() throws InterruptedException {
|
||||
//given
|
||||
LongAdder counter = new LongAdder();
|
||||
ExecutorService executorService = Executors.newFixedThreadPool(8);
|
||||
|
||||
int numberOfThreads = 4;
|
||||
int numberOfIncrements = 100;
|
||||
|
||||
//when
|
||||
Runnable incrementAction = () -> IntStream
|
||||
.range(0, numberOfIncrements)
|
||||
.forEach((i) -> counter.increment());
|
||||
|
||||
for (int i = 0; i < numberOfThreads; i++) {
|
||||
executorService.execute(incrementAction);
|
||||
}
|
||||
|
||||
//then
|
||||
executorService.awaitTermination(500, TimeUnit.MILLISECONDS);
|
||||
executorService.shutdown();
|
||||
|
||||
assertEquals(counter.sum(), numberOfIncrements * numberOfThreads);
|
||||
assertEquals(counter.sum(), numberOfIncrements * numberOfThreads);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenMultipleThread_whenTheyWriteToSharedLongAdder_thenShouldCalculateSumForThemAndResetAdderAfterward() throws InterruptedException {
|
||||
//given
|
||||
LongAdder counter = new LongAdder();
|
||||
ExecutorService executorService = Executors.newFixedThreadPool(8);
|
||||
|
||||
int numberOfThreads = 4;
|
||||
int numberOfIncrements = 100;
|
||||
|
||||
//when
|
||||
Runnable incrementAction = () -> IntStream
|
||||
.range(0, numberOfIncrements)
|
||||
.forEach((i) -> counter.increment());
|
||||
|
||||
for (int i = 0; i < numberOfThreads; i++) {
|
||||
executorService.execute(incrementAction);
|
||||
}
|
||||
|
||||
//then
|
||||
executorService.awaitTermination(500, TimeUnit.MILLISECONDS);
|
||||
executorService.shutdown();
|
||||
|
||||
assertEquals(counter.sumThenReset(), numberOfIncrements * numberOfThreads);
|
||||
|
||||
await().until(() -> assertEquals(counter.sum(), 0));
|
||||
}
|
||||
}
|
||||
+38
@@ -0,0 +1,38 @@
|
||||
package com.baeldung.concurrent.atomic;
|
||||
|
||||
import static org.junit.Assert.assertEquals;
|
||||
|
||||
import java.util.concurrent.ExecutorService;
|
||||
import java.util.concurrent.Executors;
|
||||
import java.util.concurrent.TimeUnit;
|
||||
import java.util.stream.IntStream;
|
||||
|
||||
import org.junit.Test;
|
||||
|
||||
public class ThreadSafeCounterTest {
|
||||
|
||||
@Test
|
||||
public void givenMultiThread_whenSafeCounterWithLockIncrement() throws InterruptedException {
|
||||
ExecutorService service = Executors.newFixedThreadPool(3);
|
||||
SafeCounterWithLock safeCounter = new SafeCounterWithLock();
|
||||
|
||||
IntStream.range(0, 1000)
|
||||
.forEach(count -> service.submit(safeCounter::increment));
|
||||
service.awaitTermination(100, TimeUnit.MILLISECONDS);
|
||||
|
||||
assertEquals(1000, safeCounter.getValue());
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenMultiThread_whenSafeCounterWithoutLockIncrement() throws InterruptedException {
|
||||
ExecutorService service = Executors.newFixedThreadPool(3);
|
||||
SafeCounterWithoutLock safeCounter = new SafeCounterWithoutLock();
|
||||
|
||||
IntStream.range(0, 1000)
|
||||
.forEach(count -> service.submit(safeCounter::increment));
|
||||
service.awaitTermination(100, TimeUnit.MILLISECONDS);
|
||||
|
||||
assertEquals(1000, safeCounter.getValue());
|
||||
}
|
||||
|
||||
}
|
||||
+33
@@ -0,0 +1,33 @@
|
||||
package com.baeldung.concurrent.atomic;
|
||||
|
||||
import static org.junit.Assert.assertEquals;
|
||||
|
||||
import java.util.concurrent.ExecutorService;
|
||||
import java.util.concurrent.Executors;
|
||||
import java.util.concurrent.TimeUnit;
|
||||
import java.util.stream.IntStream;
|
||||
|
||||
import org.junit.Test;
|
||||
|
||||
/**
|
||||
* This test shows the behaviour of a thread-unsafe class in a multithreaded scenario. We are calling
|
||||
* the increment methods 1000 times from a pool of 3 threads. In most of the cases, the counter will
|
||||
* less than 1000, because of lost updates, however, occasionally it may reach 1000, when no threads
|
||||
* called the method simultaneously. This may cause the build to fail occasionally. Hence excluding this
|
||||
* test from build by adding this in manual test
|
||||
*/
|
||||
public class ThreadUnsafeCounterManualTest {
|
||||
|
||||
@Test
|
||||
public void givenMultiThread_whenUnsafeCounterIncrement() throws InterruptedException {
|
||||
ExecutorService service = Executors.newFixedThreadPool(3);
|
||||
UnsafeCounter unsafeCounter = new UnsafeCounter();
|
||||
|
||||
IntStream.range(0, 1000)
|
||||
.forEach(count -> service.submit(unsafeCounter::increment));
|
||||
service.awaitTermination(100, TimeUnit.MILLISECONDS);
|
||||
|
||||
assertEquals(1000, unsafeCounter.getValue());
|
||||
}
|
||||
|
||||
}
|
||||
+53
@@ -0,0 +1,53 @@
|
||||
package com.baeldung.concurrent.copyonwrite;
|
||||
|
||||
|
||||
import org.junit.Test;
|
||||
|
||||
import java.util.Iterator;
|
||||
import java.util.LinkedList;
|
||||
import java.util.List;
|
||||
import java.util.concurrent.CopyOnWriteArrayList;
|
||||
|
||||
import static org.assertj.core.api.Assertions.assertThat;
|
||||
|
||||
|
||||
public class CopyOnWriteArrayListUnitTest {
|
||||
|
||||
@Test
|
||||
public void givenCopyOnWriteList_whenIterateAndAddElementToUnderneathList_thenShouldNotChangeIterator() {
|
||||
//given
|
||||
final CopyOnWriteArrayList<Integer> numbers =
|
||||
new CopyOnWriteArrayList<>(new Integer[]{1, 3, 5, 8});
|
||||
|
||||
//when
|
||||
Iterator<Integer> iterator = numbers.iterator();
|
||||
numbers.add(10);
|
||||
|
||||
//then
|
||||
List<Integer> result = new LinkedList<>();
|
||||
iterator.forEachRemaining(result::add);
|
||||
assertThat(result).containsOnly(1, 3, 5, 8);
|
||||
|
||||
//and
|
||||
Iterator<Integer> iterator2 = numbers.iterator();
|
||||
List<Integer> result2 = new LinkedList<>();
|
||||
iterator2.forEachRemaining(result2::add);
|
||||
|
||||
//then
|
||||
assertThat(result2).containsOnly(1, 3, 5, 8, 10);
|
||||
|
||||
}
|
||||
|
||||
@Test(expected = UnsupportedOperationException.class)
|
||||
public void givenCopyOnWriteList_whenIterateOverItAndTryToRemoveElement_thenShouldThrowException() {
|
||||
//given
|
||||
final CopyOnWriteArrayList<Integer> numbers =
|
||||
new CopyOnWriteArrayList<>(new Integer[]{1, 3, 5, 8});
|
||||
|
||||
//when
|
||||
Iterator<Integer> iterator = numbers.iterator();
|
||||
while (iterator.hasNext()) {
|
||||
iterator.remove();
|
||||
}
|
||||
}
|
||||
}
|
||||
+70
@@ -0,0 +1,70 @@
|
||||
package com.baeldung.concurrent.countdownlatch;
|
||||
|
||||
import org.junit.Test;
|
||||
|
||||
import java.util.ArrayList;
|
||||
import java.util.Collections;
|
||||
import java.util.List;
|
||||
import java.util.concurrent.CountDownLatch;
|
||||
import java.util.concurrent.TimeUnit;
|
||||
import java.util.stream.Stream;
|
||||
|
||||
import static java.util.stream.Collectors.toList;
|
||||
import static org.assertj.core.api.Assertions.assertThat;
|
||||
|
||||
public class CountdownLatchExampleIntegrationTest {
|
||||
@Test
|
||||
public void whenParallelProcessing_thenMainThreadWillBlockUntilCompletion() throws InterruptedException {
|
||||
// Given
|
||||
List<String> outputScraper = Collections.synchronizedList(new ArrayList<>());
|
||||
CountDownLatch countDownLatch = new CountDownLatch(5);
|
||||
List<Thread> workers = Stream.generate(() -> new Thread(new Worker(outputScraper, countDownLatch))).limit(5).collect(toList());
|
||||
|
||||
// When
|
||||
workers.forEach(Thread::start);
|
||||
countDownLatch.await(); // Block until workers finish
|
||||
outputScraper.add("Latch released");
|
||||
|
||||
// Then
|
||||
outputScraper.forEach(Object::toString);
|
||||
assertThat(outputScraper).containsExactly("Counted down", "Counted down", "Counted down", "Counted down", "Counted down", "Latch released");
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenFailingToParallelProcess_thenMainThreadShouldTimeout() throws InterruptedException {
|
||||
// Given
|
||||
List<String> outputScraper = Collections.synchronizedList(new ArrayList<>());
|
||||
CountDownLatch countDownLatch = new CountDownLatch(5);
|
||||
List<Thread> workers = Stream.generate(() -> new Thread(new BrokenWorker(outputScraper, countDownLatch))).limit(5).collect(toList());
|
||||
|
||||
// When
|
||||
workers.forEach(Thread::start);
|
||||
final boolean result = countDownLatch.await(3L, TimeUnit.SECONDS);
|
||||
|
||||
// Then
|
||||
assertThat(result).isFalse();
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenDoingLotsOfThreadsInParallel_thenStartThemAtTheSameTime() throws InterruptedException {
|
||||
// Given
|
||||
List<String> outputScraper = Collections.synchronizedList(new ArrayList<>());
|
||||
CountDownLatch readyThreadCounter = new CountDownLatch(5);
|
||||
CountDownLatch callingThreadBlocker = new CountDownLatch(1);
|
||||
CountDownLatch completedThreadCounter = new CountDownLatch(5);
|
||||
List<Thread> workers = Stream.generate(() -> new Thread(new WaitingWorker(outputScraper, readyThreadCounter, callingThreadBlocker, completedThreadCounter))).limit(5).collect(toList());
|
||||
|
||||
// When
|
||||
workers.forEach(Thread::start);
|
||||
readyThreadCounter.await(); // Block until workers start
|
||||
outputScraper.add("Workers ready");
|
||||
callingThreadBlocker.countDown(); // Start workers
|
||||
completedThreadCounter.await(); // Block until workers finish
|
||||
outputScraper.add("Workers complete");
|
||||
|
||||
// Then
|
||||
outputScraper.forEach(Object::toString);
|
||||
assertThat(outputScraper).containsExactly("Workers ready", "Counted down", "Counted down", "Counted down", "Counted down", "Counted down", "Workers complete");
|
||||
}
|
||||
|
||||
}
|
||||
+82
@@ -0,0 +1,82 @@
|
||||
package com.baeldung.concurrent.delayqueue;
|
||||
|
||||
import org.junit.FixMethodOrder;
|
||||
import org.junit.Test;
|
||||
import org.junit.runners.MethodSorters;
|
||||
|
||||
import java.util.concurrent.BlockingQueue;
|
||||
import java.util.concurrent.DelayQueue;
|
||||
import java.util.concurrent.ExecutorService;
|
||||
import java.util.concurrent.Executors;
|
||||
import java.util.concurrent.TimeUnit;
|
||||
|
||||
import static junit.framework.TestCase.assertEquals;
|
||||
|
||||
@FixMethodOrder(MethodSorters.NAME_ASCENDING)
|
||||
public class DelayQueueIntegrationTest {
|
||||
@Test
|
||||
public void givenDelayQueue_whenProduceElement_thenShouldConsumeAfterGivenDelay() throws InterruptedException {
|
||||
//given
|
||||
ExecutorService executor = Executors.newFixedThreadPool(2);
|
||||
BlockingQueue<DelayObject> queue = new DelayQueue<>();
|
||||
int numberOfElementsToProduce = 2;
|
||||
int delayOfEachProducedMessageMilliseconds = 500;
|
||||
DelayQueueConsumer consumer = new DelayQueueConsumer(queue, numberOfElementsToProduce);
|
||||
DelayQueueProducer producer
|
||||
= new DelayQueueProducer(queue, numberOfElementsToProduce, delayOfEachProducedMessageMilliseconds);
|
||||
|
||||
//when
|
||||
executor.submit(producer);
|
||||
executor.submit(consumer);
|
||||
|
||||
//then
|
||||
executor.awaitTermination(5, TimeUnit.SECONDS);
|
||||
executor.shutdown();
|
||||
assertEquals(consumer.numberOfConsumedElements.get(), numberOfElementsToProduce);
|
||||
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenDelayQueue_whenProduceElementWithHugeDelay_thenConsumerWasNotAbleToConsumeMessageInGivenTime() throws InterruptedException {
|
||||
//given
|
||||
ExecutorService executor = Executors.newFixedThreadPool(2);
|
||||
BlockingQueue<DelayObject> queue = new DelayQueue<>();
|
||||
int numberOfElementsToProduce = 1;
|
||||
int delayOfEachProducedMessageMilliseconds = 10_000;
|
||||
DelayQueueConsumer consumer = new DelayQueueConsumer(queue, numberOfElementsToProduce);
|
||||
DelayQueueProducer producer
|
||||
= new DelayQueueProducer(queue, numberOfElementsToProduce, delayOfEachProducedMessageMilliseconds);
|
||||
|
||||
//when
|
||||
executor.submit(producer);
|
||||
executor.submit(consumer);
|
||||
|
||||
//then
|
||||
executor.awaitTermination(5, TimeUnit.SECONDS);
|
||||
executor.shutdown();
|
||||
assertEquals(consumer.numberOfConsumedElements.get(), 0);
|
||||
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenDelayQueue_whenProduceElementWithNegativeDelay_thenConsumeMessageImmediately() throws InterruptedException {
|
||||
//given
|
||||
ExecutorService executor = Executors.newFixedThreadPool(2);
|
||||
BlockingQueue<DelayObject> queue = new DelayQueue<>();
|
||||
int numberOfElementsToProduce = 1;
|
||||
int delayOfEachProducedMessageMilliseconds = -10_000;
|
||||
DelayQueueConsumer consumer = new DelayQueueConsumer(queue, numberOfElementsToProduce);
|
||||
DelayQueueProducer producer
|
||||
= new DelayQueueProducer(queue, numberOfElementsToProduce, delayOfEachProducedMessageMilliseconds);
|
||||
|
||||
//when
|
||||
executor.submit(producer);
|
||||
executor.submit(consumer);
|
||||
|
||||
//then
|
||||
executor.awaitTermination(1, TimeUnit.SECONDS);
|
||||
executor.shutdown();
|
||||
assertEquals(consumer.numberOfConsumedElements.get(), 1);
|
||||
|
||||
}
|
||||
}
|
||||
+22
@@ -0,0 +1,22 @@
|
||||
package com.baeldung.concurrent.future;
|
||||
|
||||
import org.junit.Test;
|
||||
|
||||
import java.util.concurrent.ForkJoinPool;
|
||||
|
||||
import static org.junit.Assert.assertEquals;
|
||||
|
||||
public class FactorialSquareCalculatorUnitTest {
|
||||
|
||||
@Test
|
||||
public void whenCalculatesFactorialSquare_thenReturnCorrectValue() {
|
||||
ForkJoinPool forkJoinPool = new ForkJoinPool();
|
||||
|
||||
FactorialSquareCalculator calculator = new FactorialSquareCalculator(10);
|
||||
|
||||
forkJoinPool.execute(calculator);
|
||||
|
||||
assertEquals("The sum of the squares from 1 to 10 is 385", 385, calculator.join().intValue());
|
||||
}
|
||||
|
||||
}
|
||||
+99
@@ -0,0 +1,99 @@
|
||||
package com.baeldung.concurrent.future;
|
||||
|
||||
import org.junit.After;
|
||||
import org.junit.Before;
|
||||
import org.junit.Rule;
|
||||
import org.junit.Test;
|
||||
import org.junit.rules.TestName;
|
||||
import org.slf4j.Logger;
|
||||
import org.slf4j.LoggerFactory;
|
||||
|
||||
import java.util.concurrent.CancellationException;
|
||||
import java.util.concurrent.ExecutionException;
|
||||
import java.util.concurrent.Executors;
|
||||
import java.util.concurrent.Future;
|
||||
import java.util.concurrent.TimeUnit;
|
||||
import java.util.concurrent.TimeoutException;
|
||||
|
||||
import static org.junit.Assert.assertEquals;
|
||||
import static org.junit.Assert.assertTrue;
|
||||
|
||||
public class SquareCalculatorIntegrationTest {
|
||||
|
||||
private static final Logger LOG = LoggerFactory.getLogger(SquareCalculatorIntegrationTest.class);
|
||||
|
||||
|
||||
@Rule
|
||||
public TestName name = new TestName();
|
||||
|
||||
private long start;
|
||||
|
||||
private SquareCalculator squareCalculator;
|
||||
|
||||
@Test
|
||||
public void givenExecutorIsSingleThreaded_whenTwoExecutionsAreTriggered_thenRunInSequence() throws InterruptedException, ExecutionException {
|
||||
squareCalculator = new SquareCalculator(Executors.newSingleThreadExecutor());
|
||||
|
||||
Future<Integer> result1 = squareCalculator.calculate(4);
|
||||
Future<Integer> result2 = squareCalculator.calculate(1000);
|
||||
|
||||
while (!result1.isDone() || !result2.isDone()) {
|
||||
LOG.debug(String.format("Task 1 is %s and Task 2 is %s.", result1.isDone() ? "done" : "not done", result2.isDone() ? "done" : "not done"));
|
||||
|
||||
Thread.sleep(300);
|
||||
}
|
||||
|
||||
assertEquals(16, result1.get().intValue());
|
||||
assertEquals(1000000, result2.get().intValue());
|
||||
}
|
||||
|
||||
@Test(expected = TimeoutException.class)
|
||||
public void whenGetWithTimeoutLowerThanExecutionTime_thenThrowException() throws InterruptedException, ExecutionException, TimeoutException {
|
||||
squareCalculator = new SquareCalculator(Executors.newSingleThreadExecutor());
|
||||
|
||||
Future<Integer> result = squareCalculator.calculate(4);
|
||||
|
||||
result.get(500, TimeUnit.MILLISECONDS);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenExecutorIsMultiThreaded_whenTwoExecutionsAreTriggered_thenRunInParallel() throws InterruptedException, ExecutionException {
|
||||
squareCalculator = new SquareCalculator(Executors.newFixedThreadPool(2));
|
||||
|
||||
Future<Integer> result1 = squareCalculator.calculate(4);
|
||||
Future<Integer> result2 = squareCalculator.calculate(1000);
|
||||
|
||||
while (!result1.isDone() || !result2.isDone()) {
|
||||
LOG.debug(String.format("Task 1 is %s and Task 2 is %s.", result1.isDone() ? "done" : "not done", result2.isDone() ? "done" : "not done"));
|
||||
|
||||
Thread.sleep(300);
|
||||
}
|
||||
|
||||
assertEquals(16, result1.get().intValue());
|
||||
assertEquals(1000000, result2.get().intValue());
|
||||
}
|
||||
|
||||
@Test(expected = CancellationException.class)
|
||||
public void whenCancelFutureAndCallGet_thenThrowException() throws InterruptedException, ExecutionException, TimeoutException {
|
||||
squareCalculator = new SquareCalculator(Executors.newSingleThreadExecutor());
|
||||
|
||||
Future<Integer> result = squareCalculator.calculate(4);
|
||||
|
||||
boolean canceled = result.cancel(true);
|
||||
|
||||
assertTrue("Future was canceled", canceled);
|
||||
assertTrue("Future was canceled", result.isCancelled());
|
||||
|
||||
result.get();
|
||||
}
|
||||
|
||||
@Before
|
||||
public void start() {
|
||||
start = System.currentTimeMillis();
|
||||
}
|
||||
|
||||
@After
|
||||
public void end() {
|
||||
LOG.debug(String.format("Test %s took %s ms \n", name.getMethodName(), System.currentTimeMillis() - start));
|
||||
}
|
||||
}
|
||||
+73
@@ -0,0 +1,73 @@
|
||||
package com.baeldung.concurrent.locks;
|
||||
|
||||
import org.junit.Test;
|
||||
|
||||
import java.util.concurrent.ExecutorService;
|
||||
import java.util.concurrent.Executors;
|
||||
|
||||
import static junit.framework.TestCase.assertEquals;
|
||||
|
||||
public class SharedObjectWithLockManualTest {
|
||||
|
||||
@Test
|
||||
public void whenLockAcquired_ThenLockedIsTrue() {
|
||||
final SharedObjectWithLock object = new SharedObjectWithLock();
|
||||
|
||||
final int threadCount = 2;
|
||||
final ExecutorService service = Executors.newFixedThreadPool(threadCount);
|
||||
|
||||
executeThreads(object, threadCount, service);
|
||||
|
||||
assertEquals(true, object.isLocked());
|
||||
|
||||
service.shutdown();
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenLocked_ThenQueuedThread() {
|
||||
final int threadCount = 4;
|
||||
final ExecutorService service = Executors.newFixedThreadPool(threadCount);
|
||||
final SharedObjectWithLock object = new SharedObjectWithLock();
|
||||
|
||||
executeThreads(object, threadCount, service);
|
||||
|
||||
assertEquals(object.hasQueuedThreads(), true);
|
||||
|
||||
service.shutdown();
|
||||
|
||||
}
|
||||
|
||||
public void whenTryLock_ThenQueuedThread() {
|
||||
final SharedObjectWithLock object = new SharedObjectWithLock();
|
||||
|
||||
final int threadCount = 2;
|
||||
final ExecutorService service = Executors.newFixedThreadPool(threadCount);
|
||||
|
||||
executeThreads(object, threadCount, service);
|
||||
|
||||
assertEquals(true, object.isLocked());
|
||||
|
||||
service.shutdown();
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenGetCount_ThenCorrectCount() throws InterruptedException {
|
||||
final int threadCount = 4;
|
||||
final ExecutorService service = Executors.newFixedThreadPool(threadCount);
|
||||
final SharedObjectWithLock object = new SharedObjectWithLock();
|
||||
|
||||
executeThreads(object, threadCount, service);
|
||||
Thread.sleep(1000);
|
||||
assertEquals(object.getCounter(), 4);
|
||||
|
||||
service.shutdown();
|
||||
|
||||
}
|
||||
|
||||
private void executeThreads(SharedObjectWithLock object, int threadCount, ExecutorService service) {
|
||||
for (int i = 0; i < threadCount; i++) {
|
||||
service.execute(object::perform);
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
+57
@@ -0,0 +1,57 @@
|
||||
package com.baeldung.concurrent.locks;
|
||||
|
||||
import org.junit.Test;
|
||||
|
||||
import java.util.concurrent.ExecutorService;
|
||||
import java.util.concurrent.Executors;
|
||||
|
||||
import static junit.framework.TestCase.assertEquals;
|
||||
|
||||
public class SynchronizedHashMapWithRWLockManualTest {
|
||||
|
||||
@Test
|
||||
public void whenWriting_ThenNoReading() {
|
||||
SynchronizedHashMapWithRWLock object = new SynchronizedHashMapWithRWLock();
|
||||
final int threadCount = 3;
|
||||
final ExecutorService service = Executors.newFixedThreadPool(threadCount);
|
||||
|
||||
executeWriterThreads(object, threadCount, service);
|
||||
|
||||
assertEquals(object.isReadLockAvailable(), false);
|
||||
|
||||
service.shutdown();
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenReading_ThenMultipleReadingAllowed() {
|
||||
SynchronizedHashMapWithRWLock object = new SynchronizedHashMapWithRWLock();
|
||||
final int threadCount = 5;
|
||||
final ExecutorService service = Executors.newFixedThreadPool(threadCount);
|
||||
|
||||
executeReaderThreads(object, threadCount, service);
|
||||
|
||||
assertEquals(object.isReadLockAvailable(), true);
|
||||
|
||||
service.shutdown();
|
||||
}
|
||||
|
||||
private void executeWriterThreads(SynchronizedHashMapWithRWLock object, int threadCount, ExecutorService service) {
|
||||
for (int i = 0; i < threadCount; i++) {
|
||||
service.execute(() -> {
|
||||
try {
|
||||
object.put("key" + threadCount, "value" + threadCount);
|
||||
} catch (InterruptedException e) {
|
||||
e.printStackTrace();
|
||||
}
|
||||
});
|
||||
}
|
||||
}
|
||||
|
||||
private void executeReaderThreads(SynchronizedHashMapWithRWLock object, int threadCount, ExecutorService service) {
|
||||
for (int i = 0; i < threadCount; i++)
|
||||
service.execute(() -> {
|
||||
object.get("key" + threadCount);
|
||||
});
|
||||
}
|
||||
|
||||
}
|
||||
+41
@@ -0,0 +1,41 @@
|
||||
package com.baeldung.concurrent.phaser;
|
||||
|
||||
import org.junit.FixMethodOrder;
|
||||
import org.junit.Test;
|
||||
import org.junit.runners.MethodSorters;
|
||||
|
||||
import java.util.concurrent.ExecutorService;
|
||||
import java.util.concurrent.Executors;
|
||||
import java.util.concurrent.Phaser;
|
||||
|
||||
import static junit.framework.TestCase.assertEquals;
|
||||
|
||||
@FixMethodOrder(MethodSorters.NAME_ASCENDING)
|
||||
public class PhaserUnitTest {
|
||||
|
||||
@Test
|
||||
public void givenPhaser_whenCoordinateWorksBetweenThreads_thenShouldCoordinateBetweenMultiplePhases() {
|
||||
//given
|
||||
ExecutorService executorService = Executors.newCachedThreadPool();
|
||||
Phaser ph = new Phaser(1);
|
||||
assertEquals(0, ph.getPhase());
|
||||
|
||||
//when
|
||||
executorService.submit(new LongRunningAction("thread-1", ph));
|
||||
executorService.submit(new LongRunningAction("thread-2", ph));
|
||||
executorService.submit(new LongRunningAction("thread-3", ph));
|
||||
|
||||
//then
|
||||
ph.arriveAndAwaitAdvance();
|
||||
assertEquals(1, ph.getPhase());
|
||||
|
||||
//and
|
||||
executorService.submit(new LongRunningAction("thread-4", ph));
|
||||
executorService.submit(new LongRunningAction("thread-5", ph));
|
||||
ph.arriveAndAwaitAdvance();
|
||||
assertEquals(2, ph.getPhase());
|
||||
|
||||
|
||||
ph.arriveAndDeregister();
|
||||
}
|
||||
}
|
||||
+57
@@ -0,0 +1,57 @@
|
||||
package com.baeldung.concurrent.priorityblockingqueue;
|
||||
|
||||
import org.junit.Test;
|
||||
import org.slf4j.Logger;
|
||||
import org.slf4j.LoggerFactory;
|
||||
|
||||
import java.util.ArrayList;
|
||||
import java.util.concurrent.PriorityBlockingQueue;
|
||||
import java.util.concurrent.TimeUnit;
|
||||
|
||||
import static org.assertj.core.api.Assertions.assertThat;
|
||||
import static org.assertj.core.util.Lists.newArrayList;
|
||||
|
||||
public class PriorityBlockingQueueIntegrationTest {
|
||||
|
||||
private static final Logger LOG = LoggerFactory.getLogger(PriorityBlockingQueueIntegrationTest.class);
|
||||
|
||||
|
||||
@Test
|
||||
public void givenUnorderedValues_whenPolling_thenShouldOrderQueue() throws InterruptedException {
|
||||
PriorityBlockingQueue<Integer> queue = new PriorityBlockingQueue<>();
|
||||
ArrayList<Integer> polledElements = new ArrayList<>();
|
||||
|
||||
queue.add(1);
|
||||
queue.add(5);
|
||||
queue.add(2);
|
||||
queue.add(3);
|
||||
queue.add(4);
|
||||
|
||||
queue.drainTo(polledElements);
|
||||
|
||||
assertThat(polledElements).containsExactly(1, 2, 3, 4, 5);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenPollingEmptyQueue_thenShouldBlockThread() throws InterruptedException {
|
||||
PriorityBlockingQueue<Integer> queue = new PriorityBlockingQueue<>();
|
||||
|
||||
final Thread thread = new Thread(() -> {
|
||||
LOG.debug("Polling...");
|
||||
while (true) {
|
||||
try {
|
||||
Integer poll = queue.take();
|
||||
LOG.debug("Polled: " + poll);
|
||||
} catch (InterruptedException ignored) {
|
||||
}
|
||||
}
|
||||
});
|
||||
thread.start();
|
||||
|
||||
Thread.sleep(TimeUnit.SECONDS.toMillis(5));
|
||||
LOG.debug("Adding to queue");
|
||||
|
||||
queue.addAll(newArrayList(1, 5, 6, 1, 2, 6, 7));
|
||||
Thread.sleep(TimeUnit.SECONDS.toMillis(1));
|
||||
}
|
||||
}
|
||||
+114
@@ -0,0 +1,114 @@
|
||||
package com.baeldung.concurrent.semaphores;
|
||||
|
||||
import org.junit.Test;
|
||||
|
||||
import java.util.concurrent.ExecutorService;
|
||||
import java.util.concurrent.Executors;
|
||||
import java.util.stream.IntStream;
|
||||
|
||||
import static org.junit.Assert.assertEquals;
|
||||
import static org.junit.Assert.assertFalse;
|
||||
import static org.junit.Assert.assertTrue;
|
||||
|
||||
public class SemaphoresManualTest {
|
||||
|
||||
// ========= login queue ======
|
||||
|
||||
@Test
|
||||
public void givenLoginQueue_whenReachLimit_thenBlocked() {
|
||||
final int slots = 10;
|
||||
final ExecutorService executorService = Executors.newFixedThreadPool(slots);
|
||||
final LoginQueueUsingSemaphore loginQueue = new LoginQueueUsingSemaphore(slots);
|
||||
IntStream.range(0, slots)
|
||||
.forEach(user -> executorService.execute(loginQueue::tryLogin));
|
||||
executorService.shutdown();
|
||||
|
||||
assertEquals(0, loginQueue.availableSlots());
|
||||
assertFalse(loginQueue.tryLogin());
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenLoginQueue_whenLogout_thenSlotsAvailable() {
|
||||
final int slots = 10;
|
||||
final ExecutorService executorService = Executors.newFixedThreadPool(slots);
|
||||
final LoginQueueUsingSemaphore loginQueue = new LoginQueueUsingSemaphore(slots);
|
||||
IntStream.range(0, slots)
|
||||
.forEach(user -> executorService.execute(loginQueue::tryLogin));
|
||||
executorService.shutdown();
|
||||
|
||||
assertEquals(0, loginQueue.availableSlots());
|
||||
loginQueue.logout();
|
||||
assertTrue(loginQueue.availableSlots() > 0);
|
||||
assertTrue(loginQueue.tryLogin());
|
||||
}
|
||||
|
||||
// ========= delay queue =======
|
||||
|
||||
@Test
|
||||
public void givenDelayQueue_whenReachLimit_thenBlocked() {
|
||||
final int slots = 50;
|
||||
final ExecutorService executorService = Executors.newFixedThreadPool(slots);
|
||||
final DelayQueueUsingTimedSemaphore delayQueue = new DelayQueueUsingTimedSemaphore(1, slots);
|
||||
IntStream.range(0, slots)
|
||||
.forEach(user -> executorService.execute(delayQueue::tryAdd));
|
||||
executorService.shutdown();
|
||||
|
||||
assertEquals(0, delayQueue.availableSlots());
|
||||
assertFalse(delayQueue.tryAdd());
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenDelayQueue_whenTimePass_thenSlotsAvailable() throws InterruptedException {
|
||||
final int slots = 50;
|
||||
final ExecutorService executorService = Executors.newFixedThreadPool(slots);
|
||||
final DelayQueueUsingTimedSemaphore delayQueue = new DelayQueueUsingTimedSemaphore(1, slots);
|
||||
IntStream.range(0, slots)
|
||||
.forEach(user -> executorService.execute(delayQueue::tryAdd));
|
||||
executorService.shutdown();
|
||||
|
||||
assertEquals(0, delayQueue.availableSlots());
|
||||
Thread.sleep(1000);
|
||||
assertTrue(delayQueue.availableSlots() > 0);
|
||||
assertTrue(delayQueue.tryAdd());
|
||||
}
|
||||
|
||||
// ========== mutex ========
|
||||
|
||||
@Test
|
||||
public void whenMutexAndMultipleThreads_thenBlocked() throws InterruptedException {
|
||||
final int count = 5;
|
||||
final ExecutorService executorService = Executors.newFixedThreadPool(count);
|
||||
final CounterUsingMutex counter = new CounterUsingMutex();
|
||||
IntStream.range(0, count)
|
||||
.forEach(user -> executorService.execute(() -> {
|
||||
try {
|
||||
counter.increase();
|
||||
} catch (final InterruptedException e) {
|
||||
e.printStackTrace();
|
||||
}
|
||||
}));
|
||||
executorService.shutdown();
|
||||
|
||||
assertTrue(counter.hasQueuedThreads());
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenMutexAndMultipleThreads_ThenDelay_thenCorrectCount() throws InterruptedException {
|
||||
final int count = 5;
|
||||
final ExecutorService executorService = Executors.newFixedThreadPool(count);
|
||||
final CounterUsingMutex counter = new CounterUsingMutex();
|
||||
IntStream.range(0, count)
|
||||
.forEach(user -> executorService.execute(() -> {
|
||||
try {
|
||||
counter.increase();
|
||||
} catch (final InterruptedException e) {
|
||||
e.printStackTrace();
|
||||
}
|
||||
}));
|
||||
executorService.shutdown();
|
||||
assertTrue(counter.hasQueuedThreads());
|
||||
Thread.sleep(5000);
|
||||
assertFalse(counter.hasQueuedThreads());
|
||||
assertEquals(count, counter.getCount());
|
||||
}
|
||||
}
|
||||
+120
@@ -0,0 +1,120 @@
|
||||
package com.baeldung.concurrent.skiplist;
|
||||
|
||||
import org.junit.Test;
|
||||
|
||||
import java.time.ZonedDateTime;
|
||||
import java.util.UUID;
|
||||
import java.util.concurrent.ConcurrentNavigableMap;
|
||||
import java.util.concurrent.ExecutorService;
|
||||
import java.util.concurrent.Executors;
|
||||
import java.util.concurrent.TimeUnit;
|
||||
import java.util.stream.IntStream;
|
||||
|
||||
import static org.junit.Assert.assertEquals;
|
||||
import static org.junit.Assert.assertTrue;
|
||||
|
||||
public class ConcurrentSkipListSetIntegrationTest {
|
||||
|
||||
@Test
|
||||
public void givenThreadsProducingEvents_whenGetForEventsFromLastMinute_thenReturnThoseEventsInTheLockFreeWay() throws InterruptedException {
|
||||
//given
|
||||
ExecutorService executorService = Executors.newFixedThreadPool(3);
|
||||
EventWindowSort eventWindowSort = new EventWindowSort();
|
||||
int numberOfThreads = 2;
|
||||
//when
|
||||
Runnable producer = () -> IntStream
|
||||
.rangeClosed(0, 100)
|
||||
.forEach(index -> eventWindowSort.acceptEvent(new Event(ZonedDateTime
|
||||
.now()
|
||||
.minusSeconds(index), UUID
|
||||
.randomUUID()
|
||||
.toString())));
|
||||
|
||||
for (int i = 0; i < numberOfThreads; i++) {
|
||||
executorService.execute(producer);
|
||||
}
|
||||
|
||||
Thread.sleep(500);
|
||||
|
||||
ConcurrentNavigableMap<ZonedDateTime, String> eventsFromLastMinute = eventWindowSort.getEventsFromLastMinute();
|
||||
|
||||
long eventsOlderThanOneMinute = eventsFromLastMinute
|
||||
.entrySet()
|
||||
.stream()
|
||||
.filter(e -> e
|
||||
.getKey()
|
||||
.isBefore(ZonedDateTime
|
||||
.now()
|
||||
.minusMinutes(1)))
|
||||
.count();
|
||||
assertEquals(eventsOlderThanOneMinute, 0);
|
||||
|
||||
long eventYoungerThanOneMinute = eventsFromLastMinute
|
||||
.entrySet()
|
||||
.stream()
|
||||
.filter(e -> e
|
||||
.getKey()
|
||||
.isAfter(ZonedDateTime
|
||||
.now()
|
||||
.minusMinutes(1)))
|
||||
.count();
|
||||
|
||||
//then
|
||||
assertTrue(eventYoungerThanOneMinute > 0);
|
||||
|
||||
executorService.awaitTermination(1, TimeUnit.SECONDS);
|
||||
executorService.shutdown();
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenThreadsProducingEvents_whenGetForEventsOlderThanOneMinute_thenReturnThoseEventsInTheLockFreeWay() throws InterruptedException {
|
||||
//given
|
||||
ExecutorService executorService = Executors.newFixedThreadPool(3);
|
||||
EventWindowSort eventWindowSort = new EventWindowSort();
|
||||
int numberOfThreads = 2;
|
||||
//when
|
||||
Runnable producer = () -> IntStream
|
||||
.rangeClosed(0, 100)
|
||||
.forEach(index -> eventWindowSort.acceptEvent(new Event(ZonedDateTime
|
||||
.now()
|
||||
.minusSeconds(index), UUID
|
||||
.randomUUID()
|
||||
.toString())));
|
||||
|
||||
for (int i = 0; i < numberOfThreads; i++) {
|
||||
executorService.execute(producer);
|
||||
}
|
||||
|
||||
Thread.sleep(500);
|
||||
|
||||
ConcurrentNavigableMap<ZonedDateTime, String> eventsFromLastMinute = eventWindowSort.getEventsOlderThatOneMinute();
|
||||
|
||||
long eventsOlderThanOneMinute = eventsFromLastMinute
|
||||
.entrySet()
|
||||
.stream()
|
||||
.filter(e -> e
|
||||
.getKey()
|
||||
.isBefore(ZonedDateTime
|
||||
.now()
|
||||
.minusMinutes(1)))
|
||||
.count();
|
||||
assertTrue(eventsOlderThanOneMinute > 0);
|
||||
|
||||
long eventYoungerThanOneMinute = eventsFromLastMinute
|
||||
.entrySet()
|
||||
.stream()
|
||||
.filter(e -> e
|
||||
.getKey()
|
||||
.isAfter(ZonedDateTime
|
||||
.now()
|
||||
.minusMinutes(1)))
|
||||
.count();
|
||||
|
||||
//then
|
||||
assertEquals(eventYoungerThanOneMinute, 0);
|
||||
|
||||
executorService.awaitTermination(1, TimeUnit.SECONDS);
|
||||
executorService.shutdown();
|
||||
}
|
||||
|
||||
}
|
||||
+37
@@ -0,0 +1,37 @@
|
||||
package com.baeldung.concurrent.synchronize;
|
||||
|
||||
import org.junit.Test;
|
||||
|
||||
import java.util.concurrent.ExecutorService;
|
||||
import java.util.concurrent.Executors;
|
||||
import java.util.concurrent.TimeUnit;
|
||||
import java.util.stream.IntStream;
|
||||
|
||||
import static org.junit.Assert.assertEquals;
|
||||
|
||||
public class BaeldungSychronizedBlockTest {
|
||||
|
||||
@Test
|
||||
public void givenMultiThread_whenBlockSync() throws InterruptedException {
|
||||
ExecutorService service = Executors.newFixedThreadPool(3);
|
||||
BaeldungSynchronizedBlocks synchronizedBlocks = new BaeldungSynchronizedBlocks();
|
||||
|
||||
IntStream.range(0, 1000)
|
||||
.forEach(count -> service.submit(synchronizedBlocks::performSynchronisedTask));
|
||||
service.awaitTermination(100, TimeUnit.MILLISECONDS);
|
||||
|
||||
assertEquals(1000, synchronizedBlocks.getCount());
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenMultiThread_whenStaticSyncBlock() throws InterruptedException {
|
||||
ExecutorService service = Executors.newCachedThreadPool();
|
||||
|
||||
IntStream.range(0, 1000)
|
||||
.forEach(count -> service.submit(BaeldungSynchronizedBlocks::performStaticSyncTask));
|
||||
service.awaitTermination(100, TimeUnit.MILLISECONDS);
|
||||
|
||||
assertEquals(1000, BaeldungSynchronizedBlocks.getStaticCount());
|
||||
}
|
||||
|
||||
}
|
||||
+51
@@ -0,0 +1,51 @@
|
||||
package com.baeldung.concurrent.synchronize;
|
||||
|
||||
import org.junit.Ignore;
|
||||
import org.junit.Test;
|
||||
|
||||
import java.util.concurrent.ExecutorService;
|
||||
import java.util.concurrent.Executors;
|
||||
import java.util.concurrent.TimeUnit;
|
||||
import java.util.stream.IntStream;
|
||||
|
||||
import static org.junit.Assert.assertEquals;
|
||||
|
||||
public class BaeldungSynchronizeMethodsTest {
|
||||
|
||||
@Test
|
||||
@Ignore
|
||||
public void givenMultiThread_whenNonSyncMethod() throws InterruptedException {
|
||||
ExecutorService service = Executors.newFixedThreadPool(3);
|
||||
BaeldungSynchronizedMethods method = new BaeldungSynchronizedMethods();
|
||||
|
||||
IntStream.range(0, 1000)
|
||||
.forEach(count -> service.submit(method::calculate));
|
||||
service.awaitTermination(100, TimeUnit.MILLISECONDS);
|
||||
|
||||
assertEquals(1000, method.getSum());
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenMultiThread_whenMethodSync() throws InterruptedException {
|
||||
ExecutorService service = Executors.newFixedThreadPool(3);
|
||||
BaeldungSynchronizedMethods method = new BaeldungSynchronizedMethods();
|
||||
|
||||
IntStream.range(0, 1000)
|
||||
.forEach(count -> service.submit(method::synchronisedCalculate));
|
||||
service.awaitTermination(100, TimeUnit.MILLISECONDS);
|
||||
|
||||
assertEquals(1000, method.getSyncSum());
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenMultiThread_whenStaticSyncMethod() throws InterruptedException {
|
||||
ExecutorService service = Executors.newCachedThreadPool();
|
||||
|
||||
IntStream.range(0, 1000)
|
||||
.forEach(count -> service.submit(BaeldungSynchronizedMethods::syncStaticCalculate));
|
||||
service.awaitTermination(100, TimeUnit.MILLISECONDS);
|
||||
|
||||
assertEquals(1000, BaeldungSynchronizedMethods.staticSum);
|
||||
}
|
||||
|
||||
}
|
||||
+71
@@ -0,0 +1,71 @@
|
||||
package com.baeldung.concurrent.volatilekeyword;
|
||||
|
||||
import org.junit.After;
|
||||
import org.junit.Before;
|
||||
import org.junit.Test;
|
||||
|
||||
import static junit.framework.Assert.assertEquals;
|
||||
|
||||
public class SharedObjectManualTest {
|
||||
|
||||
private SharedObject sharedObject;
|
||||
private int valueReadByThread2;
|
||||
private int valueReadByThread3;
|
||||
|
||||
@Before
|
||||
public void setUp() {
|
||||
sharedObject = new SharedObject();
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenOneThreadWrites_thenVolatileReadsFromMainMemory() throws InterruptedException {
|
||||
Thread writer = new Thread(() -> sharedObject.increamentCount());
|
||||
writer.start();
|
||||
|
||||
|
||||
Thread readerOne = new Thread(() -> {
|
||||
try {
|
||||
Thread.sleep(1000);
|
||||
} catch (InterruptedException e) {
|
||||
e.printStackTrace();
|
||||
}
|
||||
valueReadByThread2 = sharedObject.getCount();
|
||||
});
|
||||
readerOne.start();
|
||||
|
||||
Thread readerTwo = new Thread(() -> {
|
||||
try {
|
||||
Thread.sleep(1000);
|
||||
} catch (InterruptedException e) {
|
||||
e.printStackTrace();
|
||||
}
|
||||
valueReadByThread3 = sharedObject.getCount();
|
||||
});
|
||||
readerTwo.start();
|
||||
|
||||
assertEquals(1, valueReadByThread2);
|
||||
assertEquals(1, valueReadByThread3);
|
||||
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenTwoThreadWrites_thenVolatileReadsFromMainMemory() throws InterruptedException {
|
||||
Thread writerOne = new Thread(() -> sharedObject.increamentCount());
|
||||
writerOne.start();
|
||||
Thread.sleep(100);
|
||||
|
||||
Thread writerTwo = new Thread(() -> sharedObject.increamentCount());
|
||||
writerTwo.start();
|
||||
Thread.sleep(100);
|
||||
|
||||
Thread readerOne = new Thread(() -> valueReadByThread2 = sharedObject.getCount());
|
||||
readerOne.start();
|
||||
|
||||
Thread readerTwo = new Thread(() -> valueReadByThread3 = sharedObject.getCount());
|
||||
readerTwo.start();
|
||||
|
||||
assertEquals(2, valueReadByThread2);
|
||||
assertEquals(2, valueReadByThread3);
|
||||
|
||||
}
|
||||
}
|
||||
+76
@@ -0,0 +1,76 @@
|
||||
package com.baeldung.java.concurrentmap;
|
||||
|
||||
import org.junit.Before;
|
||||
import org.junit.Test;
|
||||
|
||||
import java.util.ArrayList;
|
||||
import java.util.List;
|
||||
import java.util.Map;
|
||||
import java.util.concurrent.ConcurrentHashMap;
|
||||
import java.util.concurrent.ExecutorService;
|
||||
import java.util.concurrent.Executors;
|
||||
import java.util.concurrent.TimeUnit;
|
||||
|
||||
import static org.junit.Assert.assertEquals;
|
||||
import static org.junit.Assert.assertNotEquals;
|
||||
|
||||
public class ConcurrentMapAggregateStatusManualTest {
|
||||
|
||||
private ExecutorService executorService;
|
||||
private Map<String, Integer> concurrentMap;
|
||||
private List<Integer> mapSizes;
|
||||
private int MAX_SIZE = 100000;
|
||||
|
||||
@Before
|
||||
public void init() {
|
||||
executorService = Executors.newFixedThreadPool(2);
|
||||
concurrentMap = new ConcurrentHashMap<>();
|
||||
mapSizes = new ArrayList<>(MAX_SIZE);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenConcurrentMap_whenSizeWithoutConcurrentUpdates_thenCorrect() throws InterruptedException {
|
||||
Runnable collectMapSizes = () -> {
|
||||
for (int i = 0; i < MAX_SIZE; i++) {
|
||||
concurrentMap.put(String.valueOf(i), i);
|
||||
mapSizes.add(concurrentMap.size());
|
||||
}
|
||||
};
|
||||
Runnable retrieveMapData = () -> {
|
||||
for (int i = 0; i < MAX_SIZE; i++) {
|
||||
concurrentMap.get(String.valueOf(i));
|
||||
}
|
||||
};
|
||||
executorService.execute(retrieveMapData);
|
||||
executorService.execute(collectMapSizes);
|
||||
executorService.shutdown();
|
||||
executorService.awaitTermination(1, TimeUnit.MINUTES);
|
||||
|
||||
for (int i = 1; i <= MAX_SIZE; i++) {
|
||||
assertEquals("map size should be consistently reliable", i, mapSizes.get(i - 1).intValue());
|
||||
}
|
||||
assertEquals(MAX_SIZE, concurrentMap.size());
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenConcurrentMap_whenUpdatingAndGetSize_thenError() throws InterruptedException {
|
||||
Runnable collectMapSizes = () -> {
|
||||
for (int i = 0; i < MAX_SIZE; i++) {
|
||||
mapSizes.add(concurrentMap.size());
|
||||
}
|
||||
};
|
||||
Runnable updateMapData = () -> {
|
||||
for (int i = 0; i < MAX_SIZE; i++) {
|
||||
concurrentMap.put(String.valueOf(i), i);
|
||||
}
|
||||
};
|
||||
executorService.execute(updateMapData);
|
||||
executorService.execute(collectMapSizes);
|
||||
executorService.shutdown();
|
||||
executorService.awaitTermination(1, TimeUnit.MINUTES);
|
||||
|
||||
assertNotEquals("map size collected with concurrent updates not reliable", MAX_SIZE, mapSizes.get(MAX_SIZE - 1).intValue());
|
||||
assertEquals(MAX_SIZE, concurrentMap.size());
|
||||
}
|
||||
|
||||
}
|
||||
+160
@@ -0,0 +1,160 @@
|
||||
package com.baeldung.java.concurrentmap;
|
||||
|
||||
import org.junit.Before;
|
||||
import org.junit.Test;
|
||||
|
||||
import java.util.HashMap;
|
||||
import java.util.Map;
|
||||
import java.util.concurrent.ConcurrentHashMap;
|
||||
import java.util.concurrent.ConcurrentMap;
|
||||
|
||||
import static org.junit.Assert.assertNull;
|
||||
|
||||
public class ConcurrentMapNullKeyValueManualTest {
|
||||
|
||||
ConcurrentMap<String, Object> concurrentMap;
|
||||
|
||||
@Before
|
||||
public void setup() {
|
||||
concurrentMap = new ConcurrentHashMap<>();
|
||||
}
|
||||
|
||||
@Test(expected = NullPointerException.class)
|
||||
public void givenConcurrentHashMap_whenGetWithNullKey_thenThrowsNPE() {
|
||||
concurrentMap.get(null);
|
||||
}
|
||||
|
||||
@Test(expected = NullPointerException.class)
|
||||
public void givenConcurrentHashMap_whenGetOrDefaultWithNullKey_thenThrowsNPE() {
|
||||
concurrentMap.getOrDefault(null, new Object());
|
||||
}
|
||||
|
||||
@Test(expected = NullPointerException.class)
|
||||
public void givenConcurrentHashMap_whenPutWithNullKey_thenThrowsNPE() {
|
||||
concurrentMap.put(null, new Object());
|
||||
}
|
||||
|
||||
@Test(expected = NullPointerException.class)
|
||||
public void givenConcurrentHashMap_whenPutNullValue_thenThrowsNPE() {
|
||||
concurrentMap.put("test", null);
|
||||
}
|
||||
|
||||
@Test(expected = NullPointerException.class)
|
||||
public void givenConcurrentHashMapAndKeyAbsent_whenPutWithNullKey_thenThrowsNPE() {
|
||||
concurrentMap.putIfAbsent(null, new Object());
|
||||
}
|
||||
|
||||
@Test(expected = NullPointerException.class)
|
||||
public void givenConcurrentHashMapAndMapWithNullKey_whenPutNullKeyMap_thenThrowsNPE() {
|
||||
Map<String, Object> nullKeyMap = new HashMap<>();
|
||||
nullKeyMap.put(null, new Object());
|
||||
concurrentMap.putAll(nullKeyMap);
|
||||
}
|
||||
|
||||
@Test(expected = NullPointerException.class)
|
||||
public void givenConcurrentHashMapAndMapWithNullValue_whenPutNullValueMap_thenThrowsNPE() {
|
||||
Map<String, Object> nullValueMap = new HashMap<>();
|
||||
nullValueMap.put("test", null);
|
||||
concurrentMap.putAll(nullValueMap);
|
||||
}
|
||||
|
||||
@Test(expected = NullPointerException.class)
|
||||
public void givenConcurrentHashMap_whenReplaceNullKeyWithValues_thenThrowsNPE() {
|
||||
concurrentMap.replace(null, new Object(), new Object());
|
||||
}
|
||||
|
||||
@Test(expected = NullPointerException.class)
|
||||
public void givenConcurrentHashMap_whenReplaceWithNullNewValue_thenThrowsNPE() {
|
||||
Object o = new Object();
|
||||
concurrentMap.replace("test", o, null);
|
||||
}
|
||||
|
||||
@Test(expected = NullPointerException.class)
|
||||
public void givenConcurrentHashMap_whenReplaceOldNullValue_thenThrowsNPE() {
|
||||
Object o = new Object();
|
||||
concurrentMap.replace("test", null, o);
|
||||
}
|
||||
|
||||
@Test(expected = NullPointerException.class)
|
||||
public void givenConcurrentHashMap_whenReplaceWithNullValue_thenThrowsNPE() {
|
||||
concurrentMap.replace("test", null);
|
||||
}
|
||||
|
||||
@Test(expected = NullPointerException.class)
|
||||
public void givenConcurrentHashMap_whenReplaceNullKey_thenThrowsNPE() {
|
||||
concurrentMap.replace(null, "test");
|
||||
}
|
||||
|
||||
@Test(expected = NullPointerException.class)
|
||||
public void givenConcurrentHashMap_whenReplaceAllMappingNull_thenThrowsNPE() {
|
||||
concurrentMap.put("test", new Object());
|
||||
concurrentMap.replaceAll((s, o) -> null);
|
||||
}
|
||||
|
||||
@Test(expected = NullPointerException.class)
|
||||
public void givenConcurrentHashMap_whenRemoveNullKey_thenThrowsNPE() {
|
||||
concurrentMap.remove(null);
|
||||
}
|
||||
|
||||
@Test(expected = NullPointerException.class)
|
||||
public void givenConcurrentHashMap_whenRemoveNullKeyWithValue_thenThrowsNPE() {
|
||||
concurrentMap.remove(null, new Object());
|
||||
}
|
||||
|
||||
@Test(expected = NullPointerException.class)
|
||||
public void givenConcurrentHashMap_whenMergeNullKeyWithValue_thenThrowsNPE() {
|
||||
concurrentMap.merge(null, new Object(), (o, o2) -> o2);
|
||||
}
|
||||
|
||||
@Test(expected = NullPointerException.class)
|
||||
public void givenConcurrentHashMap_whenMergeKeyWithNullValue_thenThrowsNPE() {
|
||||
concurrentMap.put("test", new Object());
|
||||
concurrentMap.merge("test", null, (o, o2) -> o2);
|
||||
}
|
||||
|
||||
@Test(expected = NullPointerException.class)
|
||||
public void givenConcurrentHashMapAndAssumeKeyAbsent_whenComputeWithNullKey_thenThrowsNPE() {
|
||||
concurrentMap.computeIfAbsent(null, s -> s);
|
||||
}
|
||||
|
||||
@Test(expected = NullPointerException.class)
|
||||
public void givenConcurrentHashMapAndAssumeKeyPresent_whenComputeWithNullKey_thenThrowsNPE() {
|
||||
concurrentMap.computeIfPresent(null, (s, o) -> o);
|
||||
}
|
||||
|
||||
@Test(expected = NullPointerException.class)
|
||||
public void givenConcurrentHashMap_whenComputeWithNullKey_thenThrowsNPE() {
|
||||
concurrentMap.compute(null, (s, o) -> o);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenConcurrentHashMap_whenMergeKeyRemappingNull_thenRemovesMapping() {
|
||||
Object oldValue = new Object();
|
||||
concurrentMap.put("test", oldValue);
|
||||
concurrentMap.merge("test", new Object(), (o, o2) -> null);
|
||||
assertNull(concurrentMap.get("test"));
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenConcurrentHashMapAndKeyAbsent_whenComputeWithKeyRemappingNull_thenRemainsAbsent() {
|
||||
concurrentMap.computeIfPresent("test", (s, o) -> null);
|
||||
assertNull(concurrentMap.get("test"));
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenKeyPresent_whenComputeIfPresentRemappingNull_thenMappingRemoved() {
|
||||
Object oldValue = new Object();
|
||||
concurrentMap.put("test", oldValue);
|
||||
concurrentMap.computeIfPresent("test", (s, o) -> null);
|
||||
assertNull(concurrentMap.get("test"));
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenKeyPresent_whenComputeRemappingNull_thenMappingRemoved() {
|
||||
Object oldValue = new Object();
|
||||
concurrentMap.put("test", oldValue);
|
||||
concurrentMap.compute("test", (s, o) -> null);
|
||||
assertNull(concurrentMap.get("test"));
|
||||
}
|
||||
|
||||
}
|
||||
+95
@@ -0,0 +1,95 @@
|
||||
package com.baeldung.java.concurrentmap;
|
||||
|
||||
import org.junit.Test;
|
||||
|
||||
import java.util.Collections;
|
||||
import java.util.HashMap;
|
||||
import java.util.Hashtable;
|
||||
import java.util.Map;
|
||||
import java.util.concurrent.*;
|
||||
|
||||
import static org.junit.Assert.assertEquals;
|
||||
import static org.junit.Assert.assertTrue;
|
||||
|
||||
public class ConcurrentMapPerformanceManualTest {
|
||||
|
||||
@Test
|
||||
public void givenMaps_whenGetPut500KTimes_thenConcurrentMapFaster() throws Exception {
|
||||
Map<String, Object> hashtable = new Hashtable<>();
|
||||
Map<String, Object> synchronizedHashMap = Collections.synchronizedMap(new HashMap<>());
|
||||
Map<String, Object> concurrentHashMap = new ConcurrentHashMap<>();
|
||||
|
||||
long hashtableAvgRuntime = timeElapseForGetPut(hashtable);
|
||||
long syncHashMapAvgRuntime = timeElapseForGetPut(synchronizedHashMap);
|
||||
long concurrentHashMapAvgRuntime = timeElapseForGetPut(concurrentHashMap);
|
||||
|
||||
System.out.println(String.format("Hashtable: %s, syncHashMap: %s, ConcurrentHashMap: %s", hashtableAvgRuntime, syncHashMapAvgRuntime, concurrentHashMapAvgRuntime));
|
||||
|
||||
assertTrue(hashtableAvgRuntime > concurrentHashMapAvgRuntime);
|
||||
assertTrue(syncHashMapAvgRuntime > concurrentHashMapAvgRuntime);
|
||||
|
||||
}
|
||||
|
||||
private long timeElapseForGetPut(Map<String, Object> map) throws InterruptedException {
|
||||
ExecutorService executorService = Executors.newFixedThreadPool(4);
|
||||
long startTime = System.nanoTime();
|
||||
for (int i = 0; i < 4; i++) {
|
||||
executorService.execute(() -> {
|
||||
for (int j = 0; j < 500_000; j++) {
|
||||
int value = ThreadLocalRandom.current().nextInt(10000);
|
||||
String key = String.valueOf(value);
|
||||
map.put(key, value);
|
||||
map.get(key);
|
||||
}
|
||||
});
|
||||
}
|
||||
executorService.shutdown();
|
||||
executorService.awaitTermination(1, TimeUnit.MINUTES);
|
||||
return (System.nanoTime() - startTime) / 500_000;
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenConcurrentMap_whenKeyWithSameHashCode_thenPerformanceDegrades() throws InterruptedException {
|
||||
class SameHash {
|
||||
@Override
|
||||
public int hashCode() {
|
||||
return 1;
|
||||
}
|
||||
}
|
||||
int executeTimes = 5000;
|
||||
|
||||
Map<SameHash, Integer> mapOfSameHash = new ConcurrentHashMap<>();
|
||||
ExecutorService executorService = Executors.newFixedThreadPool(2);
|
||||
long sameHashStartTime = System.currentTimeMillis();
|
||||
for (int i = 0; i < 2; i++) {
|
||||
executorService.execute(() -> {
|
||||
for (int j = 0; j < executeTimes; j++) {
|
||||
mapOfSameHash.put(new SameHash(), 1);
|
||||
}
|
||||
});
|
||||
}
|
||||
executorService.shutdown();
|
||||
executorService.awaitTermination(5, TimeUnit.SECONDS);
|
||||
|
||||
long mapOfSameHashDuration = System.currentTimeMillis() - sameHashStartTime;
|
||||
Map<Object, Integer> mapOfDefaultHash = new ConcurrentHashMap<>();
|
||||
executorService = Executors.newFixedThreadPool(2);
|
||||
long defaultHashStartTime = System.currentTimeMillis();
|
||||
for (int i = 0; i < 2; i++) {
|
||||
executorService.execute(() -> {
|
||||
for (int j = 0; j < executeTimes; j++) {
|
||||
mapOfDefaultHash.put(new Object(), 1);
|
||||
}
|
||||
});
|
||||
}
|
||||
executorService.shutdown();
|
||||
executorService.awaitTermination(5, TimeUnit.SECONDS);
|
||||
|
||||
long mapOfDefaultHashDuration = System.currentTimeMillis() - defaultHashStartTime;
|
||||
assertEquals(executeTimes * 2, mapOfDefaultHash.size());
|
||||
assertEquals(executeTimes * 2, mapOfSameHash.size());
|
||||
System.out.println(String.format("same-hash: %s, default-hash: %s", mapOfSameHashDuration, mapOfDefaultHashDuration));
|
||||
assertTrue("same hashCode() should greatly degrade performance", mapOfSameHashDuration > mapOfDefaultHashDuration * 10);
|
||||
}
|
||||
|
||||
}
|
||||
+79
@@ -0,0 +1,79 @@
|
||||
package com.baeldung.java.concurrentmap;
|
||||
|
||||
import org.junit.Test;
|
||||
|
||||
import java.util.Iterator;
|
||||
import java.util.NavigableMap;
|
||||
import java.util.TreeMap;
|
||||
import java.util.concurrent.*;
|
||||
import java.util.concurrent.atomic.AtomicInteger;
|
||||
|
||||
import static org.junit.Assert.assertEquals;
|
||||
import static org.junit.Assert.assertNotEquals;
|
||||
import static org.junit.Assert.assertTrue;
|
||||
|
||||
public class ConcurrentNavigableMapManualTest {
|
||||
|
||||
@Test
|
||||
public void givenSkipListMap_whenAccessInMultiThreads_thenOrderingStable() throws InterruptedException {
|
||||
NavigableMap<Integer, String> skipListMap = new ConcurrentSkipListMap<>();
|
||||
|
||||
updateMapConcurrently(skipListMap, 4);
|
||||
|
||||
Iterator<Integer> skipListIter = skipListMap.keySet().iterator();
|
||||
int previous = skipListIter.next();
|
||||
while (skipListIter.hasNext()) {
|
||||
int current = skipListIter.next();
|
||||
assertTrue(previous < current);
|
||||
}
|
||||
}
|
||||
|
||||
private void updateMapConcurrently(NavigableMap<Integer, String> navigableMap, int concurrencyLevel) throws InterruptedException {
|
||||
ExecutorService executorService = Executors.newFixedThreadPool(concurrencyLevel);
|
||||
for (int i = 0; i < concurrencyLevel; i++) {
|
||||
executorService.execute(() -> {
|
||||
ThreadLocalRandom random = ThreadLocalRandom.current();
|
||||
for (int j = 0; j < 10000; j++) {
|
||||
navigableMap.put(random.nextInt(), "test");
|
||||
}
|
||||
});
|
||||
}
|
||||
executorService.shutdown();
|
||||
executorService.awaitTermination(1, TimeUnit.MINUTES);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenSkipListMap_whenNavConcurrently_thenCountCorrect() throws InterruptedException {
|
||||
NavigableMap<Integer, Integer> skipListMap = new ConcurrentSkipListMap<>();
|
||||
int count = countMapElementByPollingFirstEntry(skipListMap, 10000, 4);
|
||||
assertEquals(10000 * 4, count);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenTreeMap_whenNavConcurrently_thenCountError() throws InterruptedException {
|
||||
NavigableMap<Integer, Integer> treeMap = new TreeMap<>();
|
||||
int count = countMapElementByPollingFirstEntry(treeMap, 10000, 4);
|
||||
assertNotEquals(10000 * 4, count);
|
||||
}
|
||||
|
||||
private int countMapElementByPollingFirstEntry(NavigableMap<Integer, Integer> navigableMap, int elementCount, int concurrencyLevel) throws InterruptedException {
|
||||
for (int i = 0; i < elementCount * concurrencyLevel; i++) {
|
||||
navigableMap.put(i, i);
|
||||
}
|
||||
AtomicInteger counter = new AtomicInteger(0);
|
||||
ExecutorService executorService = Executors.newFixedThreadPool(concurrencyLevel);
|
||||
for (int j = 0; j < concurrencyLevel; j++) {
|
||||
executorService.execute(() -> {
|
||||
for (int i = 0; i < elementCount; i++) {
|
||||
if (navigableMap.pollFirstEntry() != null) {
|
||||
counter.incrementAndGet();
|
||||
}
|
||||
}
|
||||
});
|
||||
}
|
||||
executorService.shutdown();
|
||||
executorService.awaitTermination(1, TimeUnit.MINUTES);
|
||||
return counter.get();
|
||||
}
|
||||
|
||||
}
|
||||
+60
@@ -0,0 +1,60 @@
|
||||
package com.baeldung.java.concurrentmap;
|
||||
|
||||
import org.junit.Test;
|
||||
|
||||
import java.util.*;
|
||||
import java.util.concurrent.ConcurrentHashMap;
|
||||
import java.util.concurrent.ExecutorService;
|
||||
import java.util.concurrent.Executors;
|
||||
import java.util.concurrent.TimeUnit;
|
||||
|
||||
import static org.junit.Assert.*;
|
||||
|
||||
public class ConcurretMapMemoryConsistencyManualTest {
|
||||
|
||||
@Test
|
||||
public void givenConcurrentMap_whenSumParallel_thenCorrect() throws Exception {
|
||||
Map<String, Integer> map = new ConcurrentHashMap<>();
|
||||
List<Integer> sumList = parallelSum100(map, 1000);
|
||||
assertEquals(1, sumList.stream().distinct().count());
|
||||
long wrongResultCount = sumList.stream().filter(num -> num != 100).count();
|
||||
assertEquals(0, wrongResultCount);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenHashtable_whenSumParallel_thenCorrect() throws Exception {
|
||||
Map<String, Integer> map = new Hashtable<>();
|
||||
List<Integer> sumList = parallelSum100(map, 1000);
|
||||
assertEquals(1, sumList.stream().distinct().count());
|
||||
long wrongResultCount = sumList.stream().filter(num -> num != 100).count();
|
||||
assertEquals(0, wrongResultCount);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenHashMap_whenSumParallel_thenError() throws Exception {
|
||||
Map<String, Integer> map = new HashMap<>();
|
||||
List<Integer> sumList = parallelSum100(map, 100);
|
||||
assertNotEquals(1, sumList.stream().distinct().count());
|
||||
long wrongResultCount = sumList.stream().filter(num -> num != 100).count();
|
||||
assertTrue(wrongResultCount > 0);
|
||||
}
|
||||
|
||||
private List<Integer> parallelSum100(Map<String, Integer> map, int executionTimes) throws InterruptedException {
|
||||
List<Integer> sumList = new ArrayList<>(1000);
|
||||
for (int i = 0; i < executionTimes; i++) {
|
||||
map.put("test", 0);
|
||||
ExecutorService executorService = Executors.newFixedThreadPool(4);
|
||||
for (int j = 0; j < 10; j++) {
|
||||
executorService.execute(() -> {
|
||||
for (int k = 0; k < 10; k++)
|
||||
map.computeIfPresent("test", (key, value) -> value + 1);
|
||||
});
|
||||
}
|
||||
executorService.shutdown();
|
||||
executorService.awaitTermination(5, TimeUnit.SECONDS);
|
||||
sumList.add(map.get("test"));
|
||||
}
|
||||
return sumList;
|
||||
}
|
||||
|
||||
}
|
||||
+80
@@ -0,0 +1,80 @@
|
||||
package com.baeldung.java.concurrentmodification;
|
||||
|
||||
import org.junit.Test;
|
||||
|
||||
import java.util.ArrayList;
|
||||
import java.util.Collection;
|
||||
import java.util.ConcurrentModificationException;
|
||||
import java.util.Iterator;
|
||||
import java.util.List;
|
||||
|
||||
import static java.util.stream.Collectors.toList;
|
||||
import static org.assertj.core.api.Assertions.assertThat;
|
||||
import static org.assertj.core.util.Lists.newArrayList;
|
||||
|
||||
public class ConcurrentModificationUnitTest {
|
||||
@Test(expected = ConcurrentModificationException.class)
|
||||
public void givenIterating_whenRemoving_thenThrowException() throws InterruptedException {
|
||||
|
||||
List<Integer> integers = newArrayList(1, 2, 3);
|
||||
|
||||
for (Integer integer : integers) {
|
||||
integers.remove(1);
|
||||
}
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenIterating_whenUsingIteratorRemove_thenNoError() throws InterruptedException {
|
||||
|
||||
List<Integer> integers = newArrayList(1, 2, 3);
|
||||
|
||||
for (Iterator<Integer> iterator = integers.iterator(); iterator.hasNext();) {
|
||||
Integer integer = iterator.next();
|
||||
if(integer == 2) {
|
||||
iterator.remove();
|
||||
}
|
||||
}
|
||||
|
||||
assertThat(integers).containsExactly(1, 3);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenIterating_whenUsingRemovalList_thenNoError() throws InterruptedException {
|
||||
|
||||
List<Integer> integers = newArrayList(1, 2, 3);
|
||||
List<Integer> toRemove = newArrayList();
|
||||
|
||||
for (Integer integer : integers) {
|
||||
if(integer == 2) {
|
||||
toRemove.add(integer);
|
||||
}
|
||||
}
|
||||
integers.removeAll(toRemove);
|
||||
|
||||
assertThat(integers).containsExactly(1, 3);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenUsingRemoveIf_thenRemoveElements() throws InterruptedException {
|
||||
|
||||
Collection<Integer> integers = newArrayList(1, 2, 3);
|
||||
|
||||
integers.removeIf(i -> i == 2);
|
||||
|
||||
assertThat(integers).containsExactly(1, 3);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenUsingStream_thenRemoveElements() {
|
||||
Collection<Integer> integers = newArrayList(1, 2, 3);
|
||||
|
||||
List<String> collected = integers
|
||||
.stream()
|
||||
.filter(i -> i != 2)
|
||||
.map(Object::toString)
|
||||
.collect(toList());
|
||||
|
||||
assertThat(collected).containsExactly("1", "3");
|
||||
}
|
||||
|
||||
}
|
||||
Some files were not shown because too many files have changed in this diff Show More
Reference in New Issue
Block a user