Merge branch 'master' of github.com:eugenp/tutorials

core-java-modules/README.md

@@ -1,6 +1,9 @@
+## Core Java Modules
+
+This module contains modules about core Java
+
 ## Relevant articles:
 
 - [Multi-Module Maven Application with Java Modules](https://www.baeldung.com/maven-multi-module-project-java-jpms)
-- [Guide to Java FileChannel](https://www.baeldung.com/java-filechannel)
 - [Understanding the NumberFormatException in Java](https://www.baeldung.com/java-number-format-exception)
 - [Will an Error Be Caught by Catch Block in Java?](https://www.baeldung.com/java-error-catch)

core-java-modules/core-java-10/README.md

@@ -1,3 +1,6 @@
+## Core Java 10
+
+This module contains articles about Java 10 core features
 
 ### Relevant Articles: 
 

core-java-modules/core-java-10/pom.xml

@@ -1,7 +1,7 @@
+<?xml version="1.0" encoding="UTF-8"?>
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+         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>
-    <groupId>com.baeldung</groupId>
     <artifactId>core-java-10</artifactId>
     <version>0.1.0-SNAPSHOT</version>
     <name>core-java-10</name>

core-java-modules/core-java-11/README.md

@@ -1,3 +1,7 @@
+## Core Java 11
+
+This module contains articles about Java 11 core features
+
 ### Relevant articles
 
 - [Java 11 Single File Source Code](https://www.baeldung.com/java-single-file-source-code)
@@ -8,4 +12,3 @@
 - [An Introduction to Epsilon GC: A No-Op Experimental Garbage Collector](https://www.baeldung.com/jvm-epsilon-gc-garbage-collector)
 - [Guide to jlink](https://www.baeldung.com/jlink)
 - [Negate a Predicate Method Reference with Java 11](https://www.baeldung.com/java-negate-predicate-method-reference)
-- [Transforming an Empty String into an Empty Optional](https://www.baeldung.com/java-empty-string-to-empty-optional)

core-java-modules/core-java-11/pom.xml

@@ -1,9 +1,8 @@
-<project
-        xmlns="http://maven.apache.org/POM/4.0.0"
-        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-        xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         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>
-    <groupId>com.baeldung</groupId>
     <artifactId>core-java-11</artifactId>
     <version>0.1.0-SNAPSHOT</version>
     <name>core-java-11</name>
@@ -29,6 +28,27 @@
             <version>${assertj.version}</version>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>org.openjdk.jmh</groupId>
+            <artifactId>jmh-core</artifactId>
+            <version>${jmh.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.openjdk.jmh</groupId>
+            <artifactId>jmh-generator-annprocess</artifactId>
+            <version>${jmh.version}</version>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.eclipse.collections</groupId>
+            <artifactId>eclipse-collections</artifactId>
+            <version>10.0.0</version>
+        </dependency>
+        <dependency>
+            <groupId>org.eclipse.collections</groupId>
+            <artifactId>eclipse-collections-api</artifactId>
+            <version>10.0.0</version>
+        </dependency>
     </dependencies>
 
     <build>
@@ -42,6 +62,42 @@
                     <target>${maven.compiler.target.version}</target>
                 </configuration>
             </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-shade-plugin</artifactId>
+                <version>3.2.1</version>
+                <executions>
+                    <execution>
+                        <phase>package</phase>
+                        <goals>
+                            <goal>shade</goal>
+                        </goals>
+                        <configuration>
+                            <finalName>${uberjar.name}</finalName>
+                            <transformers>
+                                <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
+                                    <mainClass>org.openjdk.jmh.Main</mainClass>
+                                </transformer>
+                                <transformer implementation="org.apache.maven.plugins.shade.resource.ServicesResourceTransformer"/>
+                            </transformers>
+                            <filters>
+                                <filter>
+                                    <!--
+                                        Shading signed JARs will fail without this.
+                                        http://stackoverflow.com/questions/999489/invalid-signature-file-when-attempting-to-run-a-jar
+                                    -->
+                                    <artifact>*:*</artifact>
+                                    <excludes>
+                                        <exclude>META-INF/*.SF</exclude>
+                                        <exclude>META-INF/*.DSA</exclude>
+                                        <exclude>META-INF/*.RSA</exclude>
+                                    </excludes>
+                                </filter>
+                            </filters>
+                        </configuration>
+                    </execution>
+                </executions>
+            </plugin>
         </plugins>
     </build>
 
@@ -50,6 +106,8 @@
         <maven.compiler.target.version>11</maven.compiler.target.version>
         <guava.version>27.1-jre</guava.version>
         <assertj.version>3.11.1</assertj.version>
+        <uberjar.name>benchmarks</uberjar.name>
+        <jmh.version>1.22</jmh.version>
     </properties>
 
 </project>

core-java-modules/core-java-11/src/main/java/com/baeldung/benchmark/IntegerListFilter.java

@@ -0,0 +1,70 @@
+package com.baeldung.benchmark;
+
+import org.eclipse.collections.api.list.MutableList;
+import org.eclipse.collections.api.list.primitive.IntList;
+import org.eclipse.collections.api.list.primitive.MutableIntList;
+import org.eclipse.collections.impl.factory.primitive.IntLists;
+import org.eclipse.collections.impl.list.mutable.FastList;
+import org.eclipse.collections.impl.list.mutable.primitive.IntArrayList;
+import org.openjdk.jmh.annotations.*;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.PrimitiveIterator;
+import java.util.Random;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.TimeUnit;
+import java.util.stream.Collectors;
+
+@State(Scope.Benchmark)
+@BenchmarkMode(Mode.Throughput)
+@OutputTimeUnit(TimeUnit.SECONDS)
+@Fork(2)
+public class IntegerListFilter {
+
+    private List<Integer> jdkIntList;
+    private MutableList<Integer> ecMutableList;
+    private IntList ecIntList;
+    private ExecutorService executor;
+
+    @Setup
+    public void setup() {
+        PrimitiveIterator.OfInt iterator = new Random(1L).ints(-10000, 10000).iterator();
+        ecMutableList = FastList.newWithNValues(1_000_000, iterator::nextInt);
+        jdkIntList = new ArrayList<>(1_000_000);
+        jdkIntList.addAll(ecMutableList);
+        ecIntList = ecMutableList.collectInt(i -> i, new IntArrayList(1_000_000));
+        executor = Executors.newWorkStealingPool();
+    }
+
+    @Benchmark
+    public List<Integer> jdkList() {
+        return jdkIntList.stream().filter(i -> i % 5 == 0).collect(Collectors.toList());
+    }
+
+    @Benchmark
+    public MutableList<Integer> ecMutableList() {
+        return ecMutableList.select(i -> i % 5 == 0);
+    }
+
+    @Benchmark
+    public List<Integer> jdkListParallel() {
+        return jdkIntList.parallelStream().filter(i -> i % 5 == 0).collect(Collectors.toList());
+    }
+
+    @Benchmark
+    public MutableList<Integer> ecMutableListParallel() {
+        return ecMutableList.asParallel(executor, 100_000).select(i -> i % 5 == 0).toList();
+    }
+
+    @Benchmark
+    public IntList ecPrimitive() {
+        return this.ecIntList.select(i -> i % 5 == 0);
+    }
+
+    @Benchmark
+    public IntList ecPrimitiveParallel() {
+        return this.ecIntList.primitiveParallelStream().filter(i -> i % 5 == 0).collect(IntLists.mutable::empty, MutableIntList::add, MutableIntList::addAll);
+    }
+}

core-java-modules/core-java-11/src/main/java/com/baeldung/benchmark/IntegerListSum.java

@@ -0,0 +1,67 @@
+package com.baeldung.benchmark;
+
+import org.eclipse.collections.api.list.MutableList;
+import org.eclipse.collections.api.list.primitive.IntList;
+import org.eclipse.collections.impl.list.mutable.FastList;
+import org.eclipse.collections.impl.list.mutable.primitive.IntArrayList;
+import org.openjdk.jmh.annotations.*;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.PrimitiveIterator;
+import java.util.Random;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.TimeUnit;
+
+@State(Scope.Benchmark)
+@BenchmarkMode(Mode.Throughput)
+@OutputTimeUnit(TimeUnit.SECONDS)
+@Fork(2)
+public class IntegerListSum {
+
+    private List<Integer> jdkIntList;
+    private MutableList<Integer> ecMutableList;
+    private ExecutorService executor;
+    private IntList ecIntList;
+
+    @Setup
+    public void setup() {
+        PrimitiveIterator.OfInt iterator = new Random(1L).ints(-10000, 10000).iterator();
+        ecMutableList = FastList.newWithNValues(1_000_000, iterator::nextInt);
+        jdkIntList = new ArrayList<>(1_000_000);
+        jdkIntList.addAll(ecMutableList);
+        ecIntList = ecMutableList.collectInt(i -> i, new IntArrayList(1_000_000));
+        executor = Executors.newWorkStealingPool();
+    }
+
+    @Benchmark
+    public long jdkList() {
+        return jdkIntList.stream().mapToLong(i -> i).sum();
+    }
+
+    @Benchmark
+    public long ecMutableList() {
+        return ecMutableList.sumOfInt(i -> i);
+    }
+
+    @Benchmark
+    public long jdkListParallel() {
+        return jdkIntList.parallelStream().mapToLong(i -> i).sum();
+    }
+
+    @Benchmark
+    public long ecMutableListParallel() {
+        return ecMutableList.asParallel(executor, 100_000).sumOfInt(i -> i);
+    }
+
+    @Benchmark
+    public long ecPrimitive() {
+        return this.ecIntList.sum();
+    }
+
+    @Benchmark
+    public long ecPrimitiveParallel() {
+        return this.ecIntList.primitiveParallelStream().sum();
+    }
+}

core-java-modules/core-java-11/src/test/java/com/baeldung/benchmark/IntegerListFilterUnitTest.java

@@ -0,0 +1,33 @@
+package com.baeldung.benchmark;
+
+import org.junit.Before;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+
+public class IntegerListFilterUnitTest {
+
+    private IntegerListFilter integerListFilter;
+
+    @Before
+    public void init() {
+        integerListFilter = new IntegerListFilter();
+        integerListFilter.setup();
+    }
+
+    @Test
+    public void whenBenchmarkIsExecute_thenJDKListsMustBeOfSameSize() {
+        assertEquals(integerListFilter.jdkList().size(), integerListFilter.jdkListParallel().size());
+    }
+
+    @Test
+    public void whenBenchmarkIsExecute_thenMutableListsMustBeOfSameSize() {
+        assertEquals(integerListFilter.ecMutableList().size(), integerListFilter.ecMutableListParallel().size());
+    }
+
+    @Test
+    public void whenBenchmarkIsExecute_thenPrimitiveListsMustBeOfSameSize() {
+        assertEquals(integerListFilter.ecPrimitive().size(), integerListFilter.ecPrimitiveParallel().size());
+    }
+}

core-java-modules/core-java-11/src/test/java/com/baeldung/benchmark/IntegerListSumUnitTest.java

@@ -0,0 +1,33 @@
+package com.baeldung.benchmark;
+
+import org.junit.Before;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+
+public class IntegerListSumUnitTest {
+
+    private IntegerListSum integerListSum;
+
+    @Before
+    public void init() {
+        integerListSum = new IntegerListSum();
+        integerListSum.setup();
+    }
+
+    @Test
+    public void whenBenchmarkIsExecute_thenJDKListsMustHaveSameValue() {
+        assertEquals(integerListSum.jdkList(), integerListSum.jdkListParallel());
+    }
+
+    @Test
+    public void whenBenchmarkIsExecute_thenMutableListsMustHaveSameValue() {
+        assertEquals(integerListSum.ecMutableList(), integerListSum.ecMutableListParallel());
+    }
+
+    @Test
+    public void whenBenchmarkIsExecute_thenPrimitiveListsMustHaveSameValue() {
+        assertEquals(integerListSum.ecPrimitive(), integerListSum.ecPrimitiveParallel());
+    }
+}

core-java-modules/core-java-11/src/test/resources/sample.txt

@@ -0,0 +1 @@
+Sample file content

core-java-modules/core-java-12/pom.xml

@@ -1,9 +1,8 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project xmlns="http://maven.apache.org/POM/4.0.0"
-    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         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>
-    <groupId>com.baeldung</groupId>
     <artifactId>core-java-12</artifactId>
     <version>0.1.0-SNAPSHOT</version>
     <name>core-java-12</name>

core-java-modules/core-java-8-2/README.md

@@ -1,10 +1,11 @@
-=========
+## Core Java 8 (part 2)
 
-## Core Java 8 Cookbooks and Examples (part 2)
+This module contains articles about Java 8 core features
 
 ### Relevant Articles: 
-- [Anonymous Classes in Java](http://www.baeldung.com/)
+- [Anonymous Classes in Java](https://www.baeldung.com/java-anonymous-classes)
 - [How to Delay Code Execution in Java](https://www.baeldung.com/java-delay-code-execution)
-- [Run JAR Application With Command Line Arguments](https://www.baeldung.com/java-run-jar-with-arguments)
+- [Run a Java Application from the Command Line](https://www.baeldung.com/java-run-jar-with-arguments)
 - [Java 8 Stream skip() vs limit()](https://www.baeldung.com/java-stream-skip-vs-limit)
 - [Guide to Java BiFunction Interface](https://www.baeldung.com/java-bifunction-interface)
+- [[<-- Prev]](/core-java-modules/core-java-8)

core-java-modules/core-java-8-2/pom.xml

@@ -1,9 +1,8 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project xmlns="http://maven.apache.org/POM/4.0.0"
-    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         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>
-    <groupId>com.baeldung</groupId>
     <artifactId>core-java-8-2</artifactId>
     <version>0.1.0-SNAPSHOT</version>
     <name>core-java-8-2</name>
@@ -30,25 +29,9 @@
         </dependency>
     </dependencies>
 
-    <build>
-        <plugins>
-            <plugin>
-                <groupId>org.apache.maven.plugins</groupId>
-                <artifactId>maven-compiler-plugin</artifactId>
-                <version>${maven-compiler-plugin.version}</version>
-                <configuration>
-                    <source>${maven.compiler.source}</source>
-                    <target>${maven.compiler.target}</target>
-                </configuration>
-            </plugin>
-        </plugins>
-    </build>
-
     <properties>
-        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-        <maven.compiler.source>1.8</maven.compiler.source>
-        <maven.compiler.target>1.8</maven.compiler.target>
         <icu.version>64.2</icu.version>
         <assertj.version>3.12.2</assertj.version>
     </properties>
+
 </project>

core-java-modules/core-java-8-2/src/main/resources/META-INF/persistence.xml

@@ -5,14 +5,14 @@
 	version="2.0">
 
 	<persistence-unit
-		name="com.baeldung.optionalReturnType"
+		name="com.baeldung.optionalreturntype"
 		transaction-type="RESOURCE_LOCAL">
 		<description>Persist Optional Return Type Demo</description>
 		<provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
-		<class>com.baeldung.optionalReturnType.User</class>
-		<class>com.baeldung.optionalReturnType.UserOptional</class>
+		<class>com.baeldung.optionalreturntype.User</class>
+		<class>com.baeldung.optionalreturntype.UserOptional</class>
 		<!-- 
-		<class>com.baeldung.optionalReturnType.UserOptionalField</class>
+		<class>com.baeldung.optionalreturntype.UserOptionalField</class>
 		-->
 		<exclude-unlisted-classes>true</exclude-unlisted-classes>
 

core-java-modules/core-java-8/README.md

@@ -1,38 +1,15 @@
-=========
+## Core Java 8
 
-## Core Java 8 Cookbooks and Examples
+This module contains articles about Java 8 core features
 
 ### Relevant Articles: 
-- [Guide to Java 8’s Collectors](http://www.baeldung.com/java-8-collectors)
-- [New Features in Java 8](http://www.baeldung.com/java-8-new-features)
-- [The Double Colon Operator in Java 8](http://www.baeldung.com/java-8-double-colon-operator)
-- [Guide to Java 8 groupingBy Collector](http://www.baeldung.com/java-groupingby-collector)
-- [Strategy Design Pattern in Java 8](http://www.baeldung.com/java-strategy-pattern)
-- [Guide to Java 8 Comparator.comparing()](http://www.baeldung.com/java-8-comparator-comparing)
-- [Guide To Java 8 Optional](http://www.baeldung.com/java-optional)
-- [Guide to the Java 8 forEach](http://www.baeldung.com/foreach-java)
-- [The Difference Between map() and flatMap()](http://www.baeldung.com/java-difference-map-and-flatmap)
-- [Static and Default Methods in Interfaces in Java](http://www.baeldung.com/java-static-default-methods)
-- [Efficient Word Frequency Calculator in Java](http://www.baeldung.com/java-word-frequency)
-- [Introduction to Spliterator in Java](http://www.baeldung.com/java-spliterator)
-- [Java 8 Math New Methods](http://www.baeldung.com/java-8-math)
-- [Overview of Java Built-in Annotations](http://www.baeldung.com/java-default-annotations)
-- [Finding Min/Max in an Array with Java](http://www.baeldung.com/java-array-min-max)
-- [Internationalization and Localization in Java 8](http://www.baeldung.com/java-8-localization)
-- [Java Optional – orElse() vs orElseGet()](http://www.baeldung.com/java-optional-or-else-vs-or-else-get)
-- [Method Parameter Reflection in Java](http://www.baeldung.com/java-parameter-reflection)
-- [Java 8 Unsigned Arithmetic Support](http://www.baeldung.com/java-unsigned-arithmetic)
-- [Generalized Target-Type Inference in Java](http://www.baeldung.com/java-generalized-target-type-inference)
-- [Overriding System Time for Testing in Java](http://www.baeldung.com/java-override-system-time)
-- [Set the Time Zone of a Date in Java](https://www.baeldung.com/java-set-date-time-zone)
-- [An Overview of Regular Expressions Performance in Java](https://www.baeldung.com/java-regex-performance)
-- [Java Primitives versus Objects](https://www.baeldung.com/java-primitives-vs-objects)
-- [How to Use if/else Logic in Java 8 Streams](https://www.baeldung.com/java-8-streams-if-else-logic)
-- [How to Replace Many if Statements in Java](https://www.baeldung.com/java-replace-if-statements)
-- [Java @Override Annotation](https://www.baeldung.com/java-override)
-- [Java @SuppressWarnings Annotation](https://www.baeldung.com/java-suppresswarnings)
-- [Java @SafeVarargs Annotation](https://www.baeldung.com/java-safevarargs)
-- [Java @Deprecated Annotation](https://www.baeldung.com/java-deprecated)
-- [Java 8 Predicate Chain](https://www.baeldung.com/java-predicate-chain)
-- [Creating a Custom Annotation in Java](https://www.baeldung.com/java-custom-annotation)
-- [The Difference Between Collection.stream().forEach() and Collection.forEach()](https://www.baeldung.com/java-collection-stream-foreach)
+- [New Features in Java 8](https://www.baeldung.com/java-8-new-features)
+- [Guide to Java 8 groupingBy Collector](https://www.baeldung.com/java-groupingby-collector)
+- [Strategy Design Pattern in Java 8](https://www.baeldung.com/java-strategy-pattern)
+- [Guide to Java 8 Comparator.comparing()](https://www.baeldung.com/java-8-comparator-comparing)
+- [Guide to the Java 8 forEach](https://www.baeldung.com/foreach-java)
+- [Introduction to Spliterator in Java](https://www.baeldung.com/java-spliterator)
+- [Finding Min/Max in an Array with Java](https://www.baeldung.com/java-array-min-max)
+- [Internationalization and Localization in Java 8](https://www.baeldung.com/java-8-localization)
+- [Generalized Target-Type Inference in Java](https://www.baeldung.com/java-generalized-target-type-inference)
+- [[More -->]](/core-java-modules/core-java-8-2)

core-java-modules/core-java-8/pom.xml

@@ -1,7 +1,7 @@
+<?xml version="1.0" encoding="UTF-8"?>
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          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>
-    <groupId>com.baeldung</groupId>
     <artifactId>core-java-8</artifactId>
     <version>0.1.0-SNAPSHOT</version>
     <name>core-java-8</name>
@@ -20,31 +20,11 @@
             <artifactId>commons-collections4</artifactId>
             <version>${commons-collections4.version}</version>
         </dependency>
-        <dependency>
-            <groupId>commons-io</groupId>
-            <artifactId>commons-io</artifactId>
-            <version>${commons-io.version}</version>
-        </dependency>
-        <dependency>
-            <groupId>org.apache.commons</groupId>
-            <artifactId>commons-lang3</artifactId>
-            <version>${commons-lang3.version}</version>
-        </dependency>
-        <dependency>
-            <groupId>org.apache.commons</groupId>
-            <artifactId>commons-math3</artifactId>
-            <version>${commons-math3.version}</version>
-        </dependency>
         <dependency>
             <groupId>log4j</groupId>
             <artifactId>log4j</artifactId>
             <version>${log4j.version}</version>
         </dependency>
-        <dependency>
-            <groupId>commons-codec</groupId>
-            <artifactId>commons-codec</artifactId>
-            <version>${commons-codec.version}</version>
-        </dependency>
         <dependency>
             <groupId>org.projectlombok</groupId>
             <artifactId>lombok</artifactId>
@@ -58,70 +38,6 @@
             <version>${assertj.version}</version>
             <scope>test</scope>
         </dependency>
-        <dependency>
-            <groupId>com.jayway.awaitility</groupId>
-            <artifactId>awaitility</artifactId>
-            <version>${avaitility.version}</version>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
-            <groupId>org.openjdk.jmh</groupId>
-            <artifactId>jmh-core</artifactId>
-            <version>${jmh-core.version}</version>
-        </dependency>
-        <dependency>
-            <groupId>org.openjdk.jmh</groupId>
-            <artifactId>jmh-generator-annprocess</artifactId>
-            <version>${jmh-generator.version}</version>
-        </dependency>
-        <dependency>
-            <groupId>org.openjdk.jmh</groupId>
-            <artifactId>jmh-generator-bytecode</artifactId>
-            <version>${jmh-generator.version}</version>
-        </dependency>
-        <dependency>
-            <groupId>com.codepoetics</groupId>
-            <artifactId>protonpack</artifactId>
-            <version>${protonpack.version}</version>
-        </dependency>
-        <dependency>
-            <groupId>io.vavr</groupId>
-            <artifactId>vavr</artifactId>
-            <version>${vavr.version}</version>
-        </dependency>
-        <dependency>
-            <groupId>joda-time</groupId>
-            <artifactId>joda-time</artifactId>
-            <version>${joda.version}</version>
-        </dependency>
-        <dependency>
-            <groupId>org.aspectj</groupId>
-            <artifactId>aspectjrt</artifactId>
-            <version>${asspectj.version}</version>
-        </dependency>
-        <dependency>
-            <groupId>org.aspectj</groupId>
-            <artifactId>aspectjweaver</artifactId>
-            <version>${asspectj.version}</version>
-        </dependency>
-        <dependency>
-            <groupId>org.powermock</groupId>
-            <artifactId>powermock-module-junit4</artifactId>
-            <version>${powermock.version}</version>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
-            <groupId>org.powermock</groupId>
-            <artifactId>powermock-api-mockito2</artifactId>
-            <version>${powermock.version}</version>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
-            <groupId>org.jmockit</groupId>
-            <artifactId>jmockit</artifactId>
-            <version>${jmockit.version}</version>
-            <scope>test</scope>
-        </dependency>
     </dependencies>
 
     <build>
@@ -134,16 +50,6 @@
         </resources>
 
         <plugins>
-            <plugin>
-                <groupId>org.apache.maven.plugins</groupId>
-                <artifactId>maven-compiler-plugin</artifactId>
-                <version>${maven-compiler-plugin.version}</version>
-                <configuration>
-                    <source>1.8</source>
-                    <target>1.8</target>
-                    <compilerArgument>-parameters</compilerArgument>
-                </configuration>
-            </plugin>
             <plugin>
                 <groupId>org.springframework.boot</groupId>
                 <artifactId>spring-boot-maven-plugin</artifactId>
@@ -160,39 +66,16 @@
                     </execution>
                 </executions>
             </plugin>
-            <plugin>
-                <artifactId>maven-surefire-plugin</artifactId>
-                <version>${maven-surefire-plugin.version}</version>
-                <configuration>
-                    <argLine>
-                        -javaagent:${settings.localRepository}/org/jmockit/jmockit/${jmockit.version}/jmockit-${jmockit.version}.jar
-                    </argLine>
-                    <disableXmlReport>true</disableXmlReport>
-                </configuration>
-            </plugin>
         </plugins>
     </build>
 
     <properties>
         <!-- util -->
-        <commons-math3.version>3.6.1</commons-math3.version>
         <commons-collections4.version>4.1</commons-collections4.version>
-        <collections-generic.version>4.01</collections-generic.version>
-        <commons-codec.version>1.10</commons-codec.version>
-        <vavr.version>0.9.0</vavr.version>
-        <protonpack.version>1.13</protonpack.version>
-        <joda.version>2.10</joda.version>
         <!-- testing -->
         <assertj.version>3.6.1</assertj.version>
-        <asspectj.version>1.8.9</asspectj.version>
-        <powermock.version>2.0.0-RC.4</powermock.version>
-        <jmockit.version>1.44</jmockit.version>
-        <avaitility.version>1.7.0</avaitility.version>
-        <jmh-core.version>1.19</jmh-core.version>
-        <jmh-generator.version>1.19</jmh-generator.version>
-        <spring-boot-maven-plugin.version>2.0.4.RELEASE</spring-boot-maven-plugin.version>
         <!-- plugins -->
-        <maven-compiler-plugin.version>3.8.0</maven-compiler-plugin.version>
-        <maven-surefire-plugin.version>2.22.1</maven-surefire-plugin.version>
+        <spring-boot-maven-plugin.version>2.0.4.RELEASE</spring-boot-maven-plugin.version>
     </properties>
+
 </project>

core-java-modules/core-java-8/src/main/java/com/baeldung/java_8_features/groupingby/Tuple.java

@@ -1,12 +1,12 @@
 package com.baeldung.java_8_features.groupingby;
 
+import java.util.Objects;
+
 public class Tuple {
+    private final BlogPostType type;
+    private final String author;
 
-    private BlogPostType type;
-    private String author;
-    
     public Tuple(BlogPostType type, String author) {
-        super();
         this.type = type;
         this.author = author;
     }
@@ -15,20 +15,27 @@ public class Tuple {
         return type;
     }
 
-    public void setType(BlogPostType type) {
-        this.type = type;
-    }
-
     public String getAuthor() {
         return author;
     }
 
-    public void setAuthor(String author) {
-        this.author = author;
+    @Override
+    public boolean equals(Object o) {
+        if (this == o)
+            return true;
+        if (o == null || getClass() != o.getClass())
+            return false;
+        Tuple tuple = (Tuple) o;
+        return type == tuple.type && author.equals(tuple.author);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(type, author);
     }
 
     @Override
     public String toString() {
-        return "Tuple [type=" + type + ", author=" + author + ", getType()=" + getType() + ", getAuthor()=" + getAuthor() + ", getClass()=" + getClass() + ", hashCode()=" + hashCode() + ", toString()=" + super.toString() + "]";
+        return "Tuple{" + "type=" + type + ", author='" + author + '\'' + '}';
     }
 }

core-java-modules/core-java-8/src/main/java/com/baeldung/optional/PersonRepository.java

@@ -1,9 +0,0 @@
-package com.baeldung.optional;
-
-public class PersonRepository {
-
-    public String findNameById(String id) {
-        return id == null ? null : "Name";
-    }
-
-}

core-java-modules/core-java-8/src/main/java/com/baeldung/reducingIfElse/AddCommand.java

@@ -1,17 +0,0 @@
-package com.baeldung.reducingIfElse;
-
-public class AddCommand implements Command {
-
-    private int a;
-    private int b;
-
-    public AddCommand(int a, int b) {
-        this.a = a;
-        this.b = b;
-    }
-
-    @Override
-    public Integer execute() {
-        return a + b;
-    }
-}

core-java-modules/core-java-8/src/main/java/com/baeldung/reducingIfElse/AddRule.java

@@ -1,21 +0,0 @@
-package com.baeldung.reducingIfElse;
-
-public class AddRule implements Rule {
-
-    private int result;
-
-    @Override
-    public boolean evaluate(Expression expression) {
-        boolean evalResult = false;
-        if (expression.getOperator() == Operator.ADD) {
-            this.result = expression.getX() + expression.getY();
-            evalResult = true;
-        }
-        return evalResult;
-    }
-
-    @Override
-    public Result getResult() {
-        return new Result(result);
-    }
-}

core-java-modules/core-java-8/src/main/java/com/baeldung/reducingIfElse/Addition.java

@@ -1,8 +0,0 @@
-package com.baeldung.reducingIfElse;
-
-public class Addition implements Operation {
-    @Override
-    public int apply(int a, int b) {
-        return a + b;
-    }
-}

core-java-modules/core-java-8/src/main/java/com/baeldung/reducingIfElse/Calculator.java

@@ -1,83 +0,0 @@
-package com.baeldung.reducingIfElse;
-
-public class Calculator {
-
-    public int calculate(int a, int b, String operator) {
-        int result = Integer.MIN_VALUE;
-
-        if ("add".equals(operator)) {
-            result = a + b;
-        } else if ("multiply".equals(operator)) {
-            result = a * b;
-        } else if ("divide".equals(operator)) {
-            result = a / b;
-        } else if ("subtract".equals(operator)) {
-            result = a - b;
-        } else if ("modulo".equals(operator)) {
-            result = a % b;
-        }
-        return result;
-    }
-
-    public int calculateUsingSwitch(int a, int b, String operator) {
-        int result = 0;
-        switch (operator) {
-        case "add":
-            result = a + b;
-            break;
-        case "multiply":
-            result = a * b;
-            break;
-        case "divide":
-            result = a / b;
-            break;
-        case "subtract":
-            result = a - b;
-            break;
-        case "modulo":
-            result = a % b;
-            break;
-        default:
-            result = Integer.MIN_VALUE;
-        }
-        return result;
-    }
-
-    public int calculateUsingSwitch(int a, int b, Operator operator) {
-        int result = 0;
-        switch (operator) {
-        case ADD:
-            result = a + b;
-            break;
-        case MULTIPLY:
-            result = a * b;
-            break;
-        case DIVIDE:
-            result = a / b;
-            break;
-        case SUBTRACT:
-            result = a - b;
-            break;
-        case MODULO:
-            result = a % b;
-            break;
-        default:
-            result = Integer.MIN_VALUE;
-        }
-        return result;
-    }
-
-    public int calculate(int a, int b, Operator operator) {
-        return operator.apply(a, b);
-    }
-
-    public int calculateUsingFactory(int a, int b, String operation) {
-        Operation targetOperation = OperatorFactory.getOperation(operation)
-            .orElseThrow(() -> new IllegalArgumentException("Invalid Operator"));
-        return targetOperation.apply(a, b);
-    }
-
-    public int calculate(Command command) {
-        return command.execute();
-    }
-}

core-java-modules/core-java-8/src/main/java/com/baeldung/reducingIfElse/Command.java

@@ -1,5 +0,0 @@
-package com.baeldung.reducingIfElse;
-
-public interface Command {
-    Integer execute();
-}

core-java-modules/core-java-8/src/main/java/com/baeldung/reducingIfElse/Division.java

@@ -1,7 +0,0 @@
-package com.baeldung.reducingIfElse;
-
-public class Division implements Operation {
-        @Override public int apply(int a, int b) {
-                return a / b;
-        }
-}

core-java-modules/core-java-8/src/main/java/com/baeldung/reducingIfElse/Expression.java

@@ -1,26 +0,0 @@
-package com.baeldung.reducingIfElse;
-
-public class Expression {
-
-        private Integer x;
-        private Integer y;
-        private Operator operator;
-
-        public Expression(Integer x, Integer y, Operator operator) {
-                this.x = x;
-                this.y = y;
-                this.operator = operator;
-        }
-
-        public Integer getX() {
-                return x;
-        }
-
-        public Integer getY() {
-                return y;
-        }
-
-        public Operator getOperator() {
-                return operator;
-        }
-}

core-java-modules/core-java-8/src/main/java/com/baeldung/reducingIfElse/Modulo.java

@@ -1,7 +0,0 @@
-package com.baeldung.reducingIfElse;
-
-public class Modulo implements Operation {
-        @Override public int apply(int a, int b) {
-                return a % b;
-        }
-}

core-java-modules/core-java-8/src/main/java/com/baeldung/reducingIfElse/Multiplication.java

@@ -1,7 +0,0 @@
-package com.baeldung.reducingIfElse;
-
-public class Multiplication implements Operation {
-        @Override public int apply(int a, int b) {
-                return 0;
-        }
-}

core-java-modules/core-java-8/src/main/java/com/baeldung/reducingIfElse/Operation.java

@@ -1,5 +0,0 @@
-package com.baeldung.reducingIfElse;
-
-public interface Operation {
-    int apply(int a, int b);
-}

core-java-modules/core-java-8/src/main/java/com/baeldung/reducingIfElse/Operator.java

@@ -1,41 +0,0 @@
-package com.baeldung.reducingIfElse;
-
-public enum Operator {
-
-    ADD {
-        @Override
-        public int apply(int a, int b) {
-            return a + b;
-        }
-    },
-
-    MULTIPLY {
-        @Override
-        public int apply(int a, int b) {
-            return a * b;
-        }
-    },
-
-    SUBTRACT {
-        @Override
-        public int apply(int a, int b) {
-            return a - b;
-        }
-    },
-
-    DIVIDE {
-        @Override
-        public int apply(int a, int b) {
-            return a / b;
-        }
-    },
-
-    MODULO {
-        @Override
-        public int apply(int a, int b) {
-            return a % b;
-        }
-    };
-
-    public abstract int apply(int a, int b);
-}

core-java-modules/core-java-8/src/main/java/com/baeldung/reducingIfElse/OperatorFactory.java

@@ -1,21 +0,0 @@
-package com.baeldung.reducingIfElse;
-
-import java.util.HashMap;
-import java.util.Map;
-import java.util.Optional;
-
-public class OperatorFactory {
-
-    static Map<String, Operation> operationMap = new HashMap<>();
-    static {
-        operationMap.put("add", new Addition());
-        operationMap.put("divide", new Division());
-        operationMap.put("multiply", new Multiplication());
-        operationMap.put("subtract", new Subtraction());
-        operationMap.put("modulo", new Modulo());
-    }
-
-    public static Optional<Operation> getOperation(String operation) {
-        return Optional.ofNullable(operationMap.get(operation));
-    }
-}