adding new article BAEL-7497 source codes

core-java-modules/core-java-collections-6/README.md

@@ -0,0 +1,7 @@
+=========
+
+## Core Java Collections Cookbooks and Examples
+
+### Relevant Articles:
+
+- More articles: [[<-- prev]](/core-java-modules/core-java-collections-5)

core-java-modules/core-java-collections-6/pom.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xmlns="http://maven.apache.org/POM/4.0.0"
+  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <artifactId>core-java-collections-6</artifactId>
+  <build>
+    <plugins>
+      <plugin>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <configuration>
+          <source>9</source>
+          <target>9</target>
+        </configuration>
+        <groupId>org.apache.maven.plugins</groupId>
+      </plugin>
+    </plugins>
+  </build>
+  <dependencies>
+    <dependency>
+      <artifactId>junit-platform-runner</artifactId>
+      <groupId>org.junit.platform</groupId>
+      <scope>test</scope>
+      <version>${junit-platform.version}</version>
+    </dependency>
+    <dependency>
+      <artifactId>junit-jupiter</artifactId>
+      <groupId>org.junit.jupiter</groupId>
+      <scope>test</scope>
+      <version>${junit.version}</version>
+    </dependency>
+    <dependency>
+      <artifactId>junit-vintage-engine</artifactId>
+      <groupId>org.junit.vintage</groupId>
+      <scope>test</scope>
+      <version>${junit.version}</version>
+    </dependency>
+  </dependencies>
+  <modelVersion>4.0.0</modelVersion>
+
+  <name>core-java-collections-6</name>
+
+  <packaging>jar</packaging>
+
+  <parent>
+    <artifactId>core-java-modules</artifactId>
+    <groupId>com.baeldung.core-java-modules</groupId>
+    <version>0.0.1-SNAPSHOT</version>
+  </parent>
+
+  <properties>
+    <junit.version>5.10.2</junit.version>
+  </properties>
+
+</project>

core-java-modules/core-java-collections-6/src/test/java/com/baeldung/iteratorvsforeach/IteratorVsForeachUnitTest.java

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+package com.baeldung.iteratorvsforeach;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertIterableEquals;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Iterator;
+import java.util.List;
+import java.util.stream.Stream;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+
+class IteratorVsForeachUnitTest {
+
+  private static Stream<Arguments> listProvider() {
+    return Stream.of(
+        Arguments.of(
+            List.of("String1", "String2", "unwanted"),
+            List.of("String1", "String2"))
+    );
+  }
+
+  @Test
+  public void givenEmptyCollection_whenUsingForEach_thenNoElementsAreIterated() {
+    List<String> names = Collections.emptyList();
+    StringBuilder stringBuilder = new StringBuilder();
+    names.forEach(stringBuilder::append);
+    assertEquals("", stringBuilder.toString());
+  }
+
+  @ParameterizedTest
+  @MethodSource("listProvider")
+  public void givenCollectionWithElements_whenRemovingElementDuringForEachIteration_thenElementIsRemoved(
+      List<String> input, List<String> expected) {
+    List<String> mutableList = new ArrayList<>(input);
+    // Separate collection for items to be removed
+    List<String> toRemove = new ArrayList<>();
+
+    // Using forEach to identify items to remove
+    input.forEach(item -> {
+      if (item.equals("unwanted")) {
+        toRemove.add(item);
+      }
+    });
+
+    // Removing the identified items from the original list
+    mutableList.removeAll(toRemove);
+    assertIterableEquals(expected, mutableList);
+  }
+
+  @ParameterizedTest
+  @MethodSource("listProvider")
+  public void givenCollectionWithElements_whenRemovingElementDuringIteratorIteration_thenElementIsRemoved(
+      List<String> input, List<String> expected) {
+    List<String> mutableList = new ArrayList<>(input);
+    Iterator<String> it = mutableList.iterator();
+    while (it.hasNext()) {
+      String item = it.next();
+      if (item.equals("unwanted")) {
+        it.remove(); // Safely remove item
+      }
+    }
+    assertIterableEquals(expected, mutableList);
+  }
+
+}

core-java-modules/pom.xml

@@ -89,6 +89,7 @@
         <module>core-java-collections-3</module>
         <module>core-java-collections-4</module>
         <module>core-java-collections-5</module>
+        <module>core-java-collections-6</module>
         <module>core-java-collections-conversions</module>
         <module>core-java-collections-set-2</module>
         <module>core-java-collections-list</module>