Merge remote-tracking branch 'upstream/master' into BAEL_4302

2020-07-25 17:26:15 +00:00
parent d52f676eda 4128525f00
commit 74ebfa24ef
324 changed files with 4452 additions and 422 deletions
@@ -8,7 +8,7 @@ This module contains articles about Java 11 core features
 - [Java 11 Local Variable Syntax for Lambda Parameters](https://www.baeldung.com/java-var-lambda-params)
 - [Java 11 String API Additions](https://www.baeldung.com/java-11-string-api)
 - [Java 11 Nest Based Access Control](https://www.baeldung.com/java-nest-based-access-control)
- [Exploring the New HTTP Client in Java 9 and 11](https://www.baeldung.com/java-9-http-client)
+- [Exploring the New HTTP Client in Java](https://www.baeldung.com/java-9-http-client)
 - [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)
@@ -1,12 +1,15 @@
 package com.baeldung.modules.main;

+import com.baeldung.modules.hello.HelloInterface;
 import com.baeldung.modules.hello.HelloModules;
+import java.util.ServiceLoader;

 public class MainApp {
    public static void main(String[] args) {
        HelloModules.doSomething();
-
-        HelloModules module = new HelloModules();
-        module.sayHello();
+        
+        Iterable<HelloInterface> services = ServiceLoader.load(HelloInterface.class);
+        HelloInterface service = services.iterator().next();
+        service.sayHello();
    }
 }
@@ -13,3 +13,4 @@ This module contains articles about core Java features that have been introduced
 - [Java 9 Platform Logging API](https://www.baeldung.com/java-9-logging-api)
 - [Java 9 Reactive Streams](https://www.baeldung.com/java-9-reactive-streams)
 - [Multi-Release JAR Files with Maven](https://www.baeldung.com/maven-multi-release-jars)
+- [The Difference between RxJava API and the Java 9 Flow API](https://www.baeldung.com/rxjava-vs-java-flow-api)
@@ -9,3 +9,4 @@ This module contains articles about Java 9 core features
 - [Iterate Through a Range of Dates in Java](https://www.baeldung.com/java-iterate-date-range)
 - [Initialize a HashMap in Java](https://www.baeldung.com/java-initialize-hashmap)
 - [Immutable ArrayList in Java](https://www.baeldung.com/java-immutable-list)
+- [Easy Ways to Write a Java InputStream to an OutputStream](https://www.baeldung.com/java-inputstream-to-outputstream)
@@ -5,4 +5,4 @@ This module contains complete guides about arrays in Java
 ### Relevant Articles: 
 - [Arrays in Java: A Reference Guide](https://www.baeldung.com/java-arrays-guide)
 - [Guide to the java.util.Arrays Class](https://www.baeldung.com/java-util-arrays)
- [What is [Ljava.lang.Object;?]](https://www.baeldung.com/java-tostring-array)
+- [What is \[Ljava.lang.Object;?](https://www.baeldung.com/java-tostring-array)
@@ -3,6 +3,7 @@
 ## Core Java Collections Cookbooks and Examples

 ### Relevant Articles: 
+
 - [Time Comparison of Arrays.sort(Object[]) and Arrays.sort(int[])](https://www.baeldung.com/arrays-sortobject-vs-sortint)
 - [Java ArrayList vs Vector](https://www.baeldung.com/java-arraylist-vs-vector)
 - [Differences Between HashMap and Hashtable](https://www.baeldung.com/hashmap-hashtable-differences)
@@ -10,3 +11,4 @@
 - [Performance of contains() in a HashSet vs ArrayList](https://www.baeldung.com/java-hashset-arraylist-contains-performance)
 - [Fail-Safe Iterator vs Fail-Fast Iterator](https://www.baeldung.com/java-fail-safe-vs-fail-fast-iterator)
 - [Quick Guide to the Java Stack](https://www.baeldung.com/java-stack)
+- [Convert an Array of Primitives to a List](https://www.baeldung.com/java-primitive-array-to-list)
@@ -15,4 +15,5 @@ This module contains articles about advanced topics about multithreading with co
 - [The ABA Problem in Concurrency](https://www.baeldung.com/cs/aba-concurrency)
 - [Introduction to Lock-Free Data Structures](https://www.baeldung.com/lock-free-programming)
 - [Introduction to Exchanger in Java](https://www.baeldung.com/java-exchanger)
+- [Why Not To Start A Thread In The Constructor?](https://www.baeldung.com/java-thread-constructor)
 - [[<-- previous]](/core-java-modules/core-java-concurrency-advanced-2)
@@ -3,10 +3,12 @@
 This module contains articles about basic Java concurrency

 ### Relevant Articles: 
+
 - [How to Delay Code Execution in Java](https://www.baeldung.com/java-delay-code-execution)
 - [wait and notify() Methods in Java](https://www.baeldung.com/java-wait-notify)
 - [Difference Between Wait and Sleep in Java](https://www.baeldung.com/java-wait-and-sleep)
 - [Guide to the Synchronized Keyword in Java](https://www.baeldung.com/java-synchronized)
 - [Life Cycle of a Thread in Java](https://www.baeldung.com/java-thread-lifecycle)
 - [Guide to AtomicMarkableReference](https://www.baeldung.com/java-atomicmarkablereference)
+- [Why are Local Variables Thread-Safe in Java](https://www.baeldung.com/java-local-variables-thread-safe)
 - [[<-- Prev]](/core-java-modules/core-java-concurrency-basic)
@@ -2,6 +2,7 @@
 This module contains articles about date operations in Java.

 ### Relevant Articles:
+
 - [Get the Current Date Prior to Java 8](https://www.baeldung.com/java-get-the-current-date-legacy)
 - [Skipping Weekends While Adding Days to LocalDate in Java 8](https://www.baeldung.com/java-localdate-add-days-skip-weekends)
 - [Checking If Two Java Dates Are on the Same Day](https://www.baeldung.com/java-check-two-dates-on-same-day)
@@ -9,4 +10,5 @@ This module contains articles about date operations in Java.
 - [How to Set the JVM Time Zone](https://www.baeldung.com/java-jvm-time-zone)
 - [How to determine day of week by passing specific date in Java?](https://www.baeldung.com/java-get-day-of-week)
 - [Finding Leap Years in Java](https://www.baeldung.com/java-leap-year)
+- [Getting the Week Number From Any Date](https://www.baeldung.com/java-get-week-number)
 - [[<-- Prev]](/core-java-modules/core-java-date-operations-1)
@@ -12,3 +12,5 @@ This module contains articles about core java exceptions
 - [Java – Try with Resources](https://www.baeldung.com/java-try-with-resources)
 - [Java Global Exception Handler](https://www.baeldung.com/java-global-exception-handler)
 - [How to Find an Exception’s Root Cause in Java](https://www.baeldung.com/java-exception-root-cause)
+- [Java IOException “Too many open files”](https://www.baeldung.com/java-too-many-open-files)
+- [When Does Java Throw the ExceptionInInitializerError?](https://www.baeldung.com/java-exceptionininitializererror)
@@ -13,4 +13,4 @@ This module contains articles about core Java input and output (IO)
 - [How to Copy a File with Java](https://www.baeldung.com/java-copy-file)
 - [Create a Directory in Java](https://www.baeldung.com/java-create-directory) 
 - [Java IO vs NIO](https://www.baeldung.com/java-io-vs-nio)
- [[<-- Prev]](/core-java-modules/core-java-io)
+- [[<-- Prev]](/core-java-modules/core-java-io)[[More -->]](/core-java-modules/core-java-io-3)
@@ -0,0 +1,9 @@
+## Core Java IO
+
+This module contains articles about core Java input and output (IO)
+
+### Relevant Articles: 
+
+- [Java – Create a File](https://www.baeldung.com/java-how-to-create-a-file)
+- [Check If a Directory Is Empty in Java](https://www.baeldung.com/java-check-empty-directory)
+- [[<-- Prev]](/core-java-modules/core-java-io-2)
@@ -0,0 +1,86 @@
+<?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>
+    <artifactId>core-java-io-3</artifactId>
+    <version>0.1.0-SNAPSHOT</version>
+    <name>core-java-io-3</name>
+    <packaging>jar</packaging>
+    <parent>
+        <groupId>com.baeldung.core-java-modules</groupId>
+        <artifactId>core-java-modules</artifactId>
+        <version>0.0.1-SNAPSHOT</version>
+        <relativePath>../</relativePath>
+    </parent>
+
+    <dependencies>
+        <!-- utils -->
+        <dependency>
+            <groupId>com.google.guava</groupId>
+            <artifactId>guava</artifactId>
+            <version>${guava.version}</version>
+        </dependency>
+        <!-- utils -->
+        <dependency>
+            <groupId>commons-io</groupId>
+            <artifactId>commons-io</artifactId>
+            <version>${commons-io.version}</version>
+        </dependency>
+        <!-- logging -->
+        <dependency>
+            <groupId>log4j</groupId>
+            <artifactId>log4j</artifactId>
+            <version>${log4j.version}</version>
+        </dependency>
+        <dependency> <!-- needed to bridge to slf4j for projects that use the log4j APIs directly -->
+            <groupId>org.slf4j</groupId>
+            <artifactId>log4j-over-slf4j</artifactId>
+            <version>${org.slf4j.version}</version>
+        </dependency>
+        <!-- test scoped -->
+        <dependency>
+            <groupId>org.assertj</groupId>
+            <artifactId>assertj-core</artifactId>
+            <version>${assertj.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <!-- https://mvnrepository.com/artifact/com.github.tomakehurst/wiremock -->
+        <dependency>
+            <groupId>com.github.tomakehurst</groupId>
+            <artifactId>wiremock</artifactId>
+            <version>${wiremock.version}</version>
+            <scope>test</scope>
+        </dependency>
+
+    </dependencies>
+
+    <build>
+        <finalName>core-java-io-3</finalName>
+        <resources>
+            <resource>
+                <directory>src/main/resources</directory>
+                <filtering>true</filtering>
+            </resource>
+        </resources>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-javadoc-plugin</artifactId>
+                <version>${maven-javadoc-plugin.version}</version>
+                <configuration>
+                    <source>${maven.compiler.source}</source>
+                    <target>${maven.compiler.target}</target>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+
+    <properties>
+        <assertj.version>3.6.1</assertj.version>
+        <maven-javadoc-plugin.version>3.0.0-M1</maven-javadoc-plugin.version>
+        <wiremock.version>2.26.3</wiremock.version>
+    </properties>
+
+</project>
@@ -0,0 +1,50 @@
+package com.baeldung.createfile;
+
+import org.apache.commons.io.FileUtils;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+public class CreateFileUnitTest {
+
+    private final String FILE_NAME = "src/test/resources/fileToCreate.txt";
+
+    @AfterEach
+    @BeforeEach
+    public void cleanUpFiles() {
+        File targetFile = new File(FILE_NAME);
+        targetFile.delete();
+    }
+
+    @Test
+    public void givenUsingNio_whenCreatingFile_thenCorrect() throws IOException {
+        Path newFilePath = Paths.get(FILE_NAME);
+        Files.createFile(newFilePath);
+    }
+
+    @Test
+    public void givenUsingFile_whenCreatingFile_thenCorrect() throws IOException {
+        File newFile = new File(FILE_NAME);
+        boolean success = newFile.createNewFile();
+        assertTrue(success);
+    }
+
+    @Test
+    public void givenUsingGuava_whenCreatingFile_thenCorrect() throws IOException {
+        com.google.common.io.Files.touch(new File(FILE_NAME));
+    }
+
+    @Test
+    public void givenUsingCommonsIo_whenCreatingFile_thenCorrect() throws IOException {
+        FileUtils.touch(new File(FILE_NAME));
+    }
+
+}
@@ -0,0 +1,63 @@
+package com.baeldung.emptiness;
+
+import org.junit.Test;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.DirectoryStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.stream.Stream;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class DirectoryEmptinessUnitTest {
+
+    @Test
+    public void givenPath_whenInvalid_thenReturnsFalse() throws IOException {
+        assertThat(isEmpty(Paths.get("invalid-addr"))).isFalse();
+    }
+
+    @Test
+    public void givenPath_whenNotDirectory_thenReturnsFalse() throws IOException {
+        Path aFile = Paths.get(getClass().getResource("/notDir.txt").getPath());
+        assertThat(isEmpty(aFile)).isFalse();
+    }
+
+    @Test
+    public void givenPath_whenNotEmptyDir_thenReturnsFalse() throws IOException {
+        Path currentDir = new File("").toPath().toAbsolutePath();
+        assertThat(isEmpty(currentDir)).isFalse();
+    }
+
+    @Test
+    public void givenPath_whenIsEmpty_thenReturnsTrue() throws Exception {
+        Path path = Files.createTempDirectory("baeldung-empty");
+        assertThat(isEmpty(path)).isTrue();
+    }
+
+    private static boolean isEmpty(Path path) throws IOException {
+        if (Files.isDirectory(path)) {
+            try (DirectoryStream<Path> directory = Files.newDirectoryStream(path)) {
+                return !directory.iterator().hasNext();
+            }
+        }
+
+        return false;
+    }
+
+    private static boolean isEmpty2(Path path) throws IOException {
+        if (Files.isDirectory(path)) {
+            try (Stream<Path> entries = Files.list(path)) {
+                return !entries.findFirst().isPresent();
+            }
+        }
+
+        return false;
+    }
+
+    private static boolean isEmptyInefficient(Path path) {
+        return path.toFile().listFiles().length == 0;
+    }
+}
@@ -7,7 +7,6 @@ This module contains articles about core Java input/output(IO) APIs.
 - [A Guide to the Java FileReader Class](https://www.baeldung.com/java-filereader)
 - [The Java File Class](https://www.baeldung.com/java-io-file)
 - [Java FileWriter](https://www.baeldung.com/java-filewriter)
- [Differences Between the Java WatchService API and the Apache Commons IO Monitor Library](https://www.baeldung.com/java-watchservice-vs-apache-commons-io-monitor-library)
 - [Comparing getPath(), getAbsolutePath(), and getCanonicalPath() in Java](https://www.baeldung.com/java-path)
 - [Quick Use of FilenameFilter](https://www.baeldung.com/java-filename-filter)
 - [Guide to BufferedReader](https://www.baeldung.com/java-buffered-reader)
@@ -1,42 +0,0 @@
-package com.baeldung.dirmonitoring;
-
-import org.apache.commons.io.monitor.FileAlterationListener;
-import org.apache.commons.io.monitor.FileAlterationListenerAdaptor;
-import org.apache.commons.io.monitor.FileAlterationMonitor;
-import org.apache.commons.io.monitor.FileAlterationObserver;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import java.io.File;
-
-public class DirectoryMonitoringExample {
-
-    private static final Logger LOG = LoggerFactory.getLogger(DirectoryMonitoringExample.class);
-
-    private static final int POLL_INTERVAL = 500;
-
-    public static void main(String[] args) throws Exception {
-        FileAlterationObserver observer = new FileAlterationObserver(System.getProperty("user.home"));
-        FileAlterationMonitor monitor = new FileAlterationMonitor(POLL_INTERVAL);
-        FileAlterationListener listener = new FileAlterationListenerAdaptor() {
-            @Override
-            public void onFileCreate(File file) {
-                LOG.debug("File: " + file.getName() + " created");
-            }
-
-            @Override
-            public void onFileDelete(File file) {
-                LOG.debug("File: " + file.getName() + " deleted");
-            }
-
-            @Override
-            public void onFileChange(File file) {
-                LOG.debug("File: " + file.getName() + " changed");
-            }
-        };
-        observer.addListener(listener);
-        monitor.addObserver(observer);
-        monitor.start();
-
-    }
-}
@@ -8,4 +8,6 @@ This module contains articles about working with the Java Virtual Machine (JVM).
 - [Measuring Object Sizes in the JVM](https://www.baeldung.com/jvm-measuring-object-sizes)
 - [Adding Shutdown Hooks for JVM Applications](https://www.baeldung.com/jvm-shutdown-hooks)
 - [boolean and boolean[] Memory Layout in the JVM](https://www.baeldung.com/jvm-boolean-memory-layout)
- More articles: [[<-- prev]](/core-java-modules/core-java-jvm)
+- [Where Is the Array Length Stored in JVM?](https://www.baeldung.com/java-jvm-array-length)
+- [Memory Address of Objects in Java](https://www.baeldung.com/java-object-memory-address)
+- More articles: [[<-- prev]](/core-java-modules/core-java-jvm)
@@ -2,4 +2,6 @@

 This module contains articles about core features in the Java language

+- [Class.isInstance vs Class.isAssignableFrom](https://www.baeldung.com/java-isinstance-isassignablefrom)
+- [Converting a Java String Into a Boolean](https://www.baeldung.com/java-string-to-boolean)
 - [[<-- Prev]](/core-java-modules/core-java-lang-2)
@@ -39,4 +39,4 @@
        <assertj.version>3.12.2</assertj.version>
    </properties>
      
-</project>
+</project>
@@ -0,0 +1,23 @@
+package com.baeldung.staticvariables;
+
+public class StaticVariableDemo {
+    public static int i;
+    public static int j = 20;
+    public static int z;
+
+    static {
+        z = 30;
+        a = 40;
+    }
+
+    public static int a = 50;
+
+    public static final int b = 100;
+
+    public StaticVariableDemo() {
+    }
+
+    static class Nested {
+        public static String nestedClassStaticVariable = "test";
+    }
+}
@@ -0,0 +1,113 @@
+package com.baeldung.staticvariables;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.lang.reflect.Field;
+
+import org.junit.jupiter.api.Test;
+
+public class StaticVariableUnitTest {
+
+    @Test
+    public void initializeStaticVariable_checkAssignedValues() {
+
+        try {
+            Class<?> staticVariableDemo = this.getClass()
+                .getClassLoader()
+                .loadClass("com.baeldung.staticvariables.StaticVariableDemo");
+
+            Field field1 = staticVariableDemo.getField("i");
+
+            assertThat(field1.getInt(staticVariableDemo)).isEqualTo(0);
+
+            Field field2 = staticVariableDemo.getField("j");
+
+            assertThat(field2.getInt(staticVariableDemo)).isEqualTo(20);
+
+        } catch (ClassNotFoundException | NoSuchFieldException | SecurityException e) {
+            e.printStackTrace();
+        } catch (IllegalArgumentException e) {
+            e.printStackTrace();
+        } catch (IllegalAccessException e) {
+            e.printStackTrace();
+        }
+
+    }
+
+    @Test
+    public void initializeStaticVariable_checkStaticBlock() {
+
+        try {
+            Class<?> staticVariableDemo = this.getClass()
+                .getClassLoader()
+                .loadClass("com.baeldung.staticvariables.StaticVariableDemo");
+
+            Field field1 = staticVariableDemo.getField("z");
+
+            assertThat(field1.getInt(staticVariableDemo)).isEqualTo(30);
+
+            Field field2 = staticVariableDemo.getField("a");
+
+            assertThat(field2.getInt(staticVariableDemo)).isEqualTo(50);
+
+        } catch (ClassNotFoundException | NoSuchFieldException | SecurityException e) {
+            e.printStackTrace();
+        } catch (IllegalArgumentException e) {
+            e.printStackTrace();
+        } catch (IllegalAccessException e) {
+            e.printStackTrace();
+        }
+
+    }
+
+    @Test
+    public void initializeStaticVariable_checkFinalValues() {
+
+        try {
+            Class<?> staticVariableDemo = this.getClass()
+                .getClassLoader()
+                .loadClass("com.baeldung.staticvariables.StaticVariableDemo");
+
+            Field field1 = staticVariableDemo.getField("b");
+
+            assertThat(field1.getInt(staticVariableDemo)).isEqualTo(100);
+
+        } catch (ClassNotFoundException | NoSuchFieldException | SecurityException e) {
+            e.printStackTrace();
+        } catch (IllegalArgumentException e) {
+            e.printStackTrace();
+        } catch (IllegalAccessException e) {
+            e.printStackTrace();
+        }
+
+    }
+
+    @Test
+    public void initializeStaticVariable_checkInnerClassValues() {
+
+        try {
+            Class<?> staticVariableDemo = this.getClass()
+                .getClassLoader()
+                .loadClass("com.baeldung.staticvariables.StaticVariableDemo");
+
+            Class<?>[] nestedClasses = staticVariableDemo.getClasses();
+
+            for (Class<?> nestedClass : nestedClasses) {
+                if (nestedClass.getName()
+                    .equals("Nested")) {
+
+                    Field field1 = nestedClass.getField("nestedClassStaticVariable");
+                    assertThat(field1.get(nestedClass)).isEqualTo("test");
+                }
+            }
+
+        } catch (ClassNotFoundException | NoSuchFieldException | SecurityException e) {
+            e.printStackTrace();
+        } catch (IllegalArgumentException e) {
+            e.printStackTrace();
+        } catch (IllegalAccessException e) {
+            e.printStackTrace();
+        }
+
+    }
+}
@@ -3,7 +3,9 @@
 This module contains articles about methods in Java

 ### Relevant Articles: 
+
 - [Methods in Java](https://www.baeldung.com/java-methods)
 - [Method Overloading and Overriding in Java](https://www.baeldung.com/java-method-overload-override)
 - [Java equals() and hashCode() Contracts](https://www.baeldung.com/java-equals-hashcode-contracts)
 - [Guide to hashCode() in Java](https://www.baeldung.com/java-hashcode)
+- [The Covariant Return Type in Java](https://www.baeldung.com/java-covariant-return-type)
@@ -12,4 +12,5 @@ This module contains articles about networking in Java
 - [Authentication with HttpUrlConnection](https://www.baeldung.com/java-http-url-connection)
 - [Download a File from an URL in Java](https://www.baeldung.com/java-download-file)
 - [Handling java.net.ConnectException](https://www.baeldung.com/java-net-connectexception)
+- [Getting MAC addresses in Java](https://www.baeldung.com/java-mac-address)
 - [[<-- Prev]](/core-java-modules/core-java-networking)
@@ -0,0 +1,3 @@
+### Relevant Articles:
+
+- [Reading the Value of ‘private’ Fields from a Different Class in Java](https://www.baeldung.com/java-reflection-read-private-field-value)
@@ -8,5 +8,4 @@
 - [Changing Annotation Parameters At Runtime](http://www.baeldung.com/java-reflection-change-annotation-params)
 - [Dynamic Proxies in Java](http://www.baeldung.com/java-dynamic-proxies)
 - [What Causes java.lang.reflect.InvocationTargetException?](https://www.baeldung.com/java-lang-reflect-invocationtargetexception)
- [How to Find all Getters Returning Null](http://www.baeldung.com/java-getters-returning-null)
 - [How to Get a Name of a Method Being Executed?](http://www.baeldung.com/java-name-of-executing-method)
@@ -3,6 +3,7 @@
 ## Core Java 8 Cookbooks and Examples

 ### Relevant Articles: 
+
 - [An Overview of Regular Expressions Performance in Java](https://www.baeldung.com/java-regex-performance)
 - [A Guide To Java Regular Expressions API](http://www.baeldung.com/regular-expressions-java)
 - [Guide to Escaping Characters in Java RegExps](http://www.baeldung.com/java-regexp-escape-char)
@@ -11,3 +12,4 @@
 - [How to Use Regular Expressions to Replace Tokens in Strings](https://www.baeldung.com/java-regex-token-replacement)
 - [Regular Expressions \s and \s+ in Java](https://www.baeldung.com/java-regex-s-splus)
 - [Validate Phone Numbers With Java Regex](https://www.baeldung.com/java-regex-validate-phone-numbers)
+- [How to Count the Number of Matches for a Regex?](https://www.baeldung.com/java-count-regex-matches)
@@ -9,4 +9,5 @@ This module contains articles about core Java Security
 - [Hashing a Password in Java](https://www.baeldung.com/java-password-hashing)
 - [SHA-256 and SHA3-256 Hashing in Java](https://www.baeldung.com/sha-256-hashing-java)
 - [Checksums in Java](https://www.baeldung.com/java-checksums)
+- [How to Read PEM File to Get Public and Private Keys](https://www.baeldung.com/java-read-pem-file-keys)
 - More articles: [[<-- prev]](/core-java-modules/core-java-security)
@@ -0,0 +1,3 @@
+### Relevant Articles:
+
+- [Version Comparison in Java](https://www.baeldung.com/java-comparing-versions)
@@ -72,6 +72,7 @@

        <module>core-java-io</module>
        <module>core-java-io-2</module>
+        <module>core-java-io-3</module>
        <module>core-java-io-apis</module>
        <module>core-java-io-conversions</module>
        <module>core-java-io-conversions-2</module>