diff --git a/core-java-modules/core-java-collections-list/src/test/java/com/ossez/collections/JavaCollectionCleanupDuplicatesTest.java b/core-java-modules/core-java-collections-list/src/test/java/com/ossez/collections/JavaCollectionCleanupDuplicatesTest.java
new file mode 100644
index 0000000000..e02be9bb42
--- /dev/null
+++ b/core-java-modules/core-java-collections-list/src/test/java/com/ossez/collections/JavaCollectionCleanupDuplicatesTest.java
@@ -0,0 +1,64 @@
+package com.ossez.collections;
+
+import com.google.common.base.Predicates;
+import com.google.common.collect.Iterables;
+import com.google.common.collect.Lists;
+import com.google.common.collect.Sets;
+import org.apache.commons.collections4.CollectionUtils;
+import org.apache.commons.collections4.PredicateUtils;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.TestInstance;
+
+import java.util.*;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.*;
+
+/**
+ * Test for list Clean up
+ *
+ * https://www.ossez.com/t/java-list/13942
+ *
+ * @author YuCheng
+ */
+@TestInstance(TestInstance.Lifecycle.PER_CLASS)
+public class JavaCollectionCleanupDuplicatesTest {
+
+ // TESTS - REMOVE DUPLICATES
+
+ @Test
+ public void givenListContainsDuplicates_whenRemovingDuplicatesWithPlainJava_thenCorrect() {
+ final List listWithDuplicates = Lists.newArrayList(5, 0, 3, 1, 2, 3, 0, 0);
+ final List listWithoutDuplicates = new ArrayList<>(new HashSet<>(listWithDuplicates));
+
+ assertThat(listWithoutDuplicates, hasSize(5));
+ assertThat(listWithoutDuplicates, containsInAnyOrder(5, 0, 3, 1, 2));
+ }
+
+ @Test
+ public void givenListContainsDuplicates_whenRemovingDuplicatesPreservingOrderWithPlainJava_thenCorrect() {
+ final List listWithDuplicates = Lists.newArrayList(5, 0, 3, 1, 2, 3, 0, 0);
+ final List listWithoutDuplicates = new ArrayList<>(new LinkedHashSet<>(listWithDuplicates));
+
+ assertThat(listWithoutDuplicates, hasSize(5));
+ assertThat(listWithoutDuplicates, containsInRelativeOrder(5, 0, 3, 1, 2));
+ }
+
+ @Test
+ public void givenListContainsDuplicates_whenRemovingDuplicatesWithGuava_thenCorrect() {
+ final List listWithDuplicates = Lists.newArrayList(5, 0, 3, 1, 2, 3, 0, 0);
+ final List listWithoutDuplicates = Lists.newArrayList(Sets.newHashSet(listWithDuplicates));
+
+ assertThat(listWithoutDuplicates, hasSize(5));
+ assertThat(listWithoutDuplicates, containsInAnyOrder(5, 0, 3, 1, 2));
+ }
+
+ @Test
+ public void givenListContainsDuplicates_whenRemovingDuplicatesPreservingOrderWithGuava_thenCorrect() {
+ final List listWithDuplicates = Lists.newArrayList(5, 0, 3, 1, 2, 3, 0, 0);
+ final List listWithoutDuplicates = Lists.newArrayList(Sets.newLinkedHashSet(listWithDuplicates));
+
+ assertThat(listWithoutDuplicates, hasSize(5));
+ assertThat(listWithoutDuplicates, containsInRelativeOrder(5, 0, 3, 1, 2));
+ }
+}
diff --git a/core-java-modules/core-java-collections-list/src/test/java/com/ossez/collections/JavaCollectionCleanupUnitTest.java b/core-java-modules/core-java-collections-list/src/test/java/com/ossez/collections/JavaCollectionCleanupUnitTest.java
index fe746b2dd0..a6b7192f92 100644
--- a/core-java-modules/core-java-collections-list/src/test/java/com/ossez/collections/JavaCollectionCleanupUnitTest.java
+++ b/core-java-modules/core-java-collections-list/src/test/java/com/ossez/collections/JavaCollectionCleanupUnitTest.java
@@ -71,7 +71,7 @@ public class JavaCollectionCleanupUnitTest {
assertThat(list, hasSize(3));
}
- // tests - remove duplicates
+ // TESTS - REMOVE DUPLICATES
@Test
public void givenListContainsDuplicates_whenRemovingDuplicatesWithPlainJava_thenCorrect() {
diff --git a/core-java-modules/core-java-collections-list/src/test/java/com/ossez/java8/Java8CollectionCleanupUnitTest.java b/core-java-modules/core-java-collections-list/src/test/java/com/ossez/java8/Java8CollectionCleanupUnitTest.java
index 6a131da3c1..96a123f7f4 100644
--- a/core-java-modules/core-java-collections-list/src/test/java/com/ossez/java8/Java8CollectionCleanupUnitTest.java
+++ b/core-java-modules/core-java-collections-list/src/test/java/com/ossez/java8/Java8CollectionCleanupUnitTest.java
@@ -2,15 +2,24 @@ package com.ossez.java8;
import com.google.common.collect.Lists;
import org.junit.Test;
+import org.junit.jupiter.api.TestInstance;
import java.util.List;
import java.util.Objects;
import java.util.stream.Collectors;
+import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.Matchers.containsInAnyOrder;
import static org.hamcrest.Matchers.hasSize;
-import static org.junit.Assert.assertThat;
+/**
+ * Test for list Clean up
+ *
+ * https://www.ossez.com/t/java-list/13942
+ *
+ * @author YuCheng
+ */
+@TestInstance(TestInstance.Lifecycle.PER_CLASS)
public class Java8CollectionCleanupUnitTest {
// tests -