BAEL-1035 Introduction to Eclipse Collections

libraries/pom.xml

@@ -453,6 +453,12 @@
 			<artifactId>pcollections</artifactId>
 			<version>${pcollections.version}</version>
 		</dependency>
+		<dependency>
+			<groupId>org.eclipse.collections</groupId>
+			<artifactId>eclipse-collections</artifactId>
+			<version>${eclipse-collections.version}</version>
+		</dependency>
+
 	</dependencies>
 	<properties>
 		<multiverse.version>0.7.0</multiverse.version>
@@ -493,5 +499,6 @@
 		<hll.version>1.6.0</hll.version>
 		<bytebuddy.version>1.7.1</bytebuddy.version>
 		<pcollections.version>2.1.2</pcollections.version>
+		<eclipse-collections.version>8.2.0</eclipse-collections.version>
 	</properties>
 </project>

libraries/src/main/java/com/baeldung/eclipsecollections/ConvertContainerToAnother.java

@@ -0,0 +1,20 @@
+package com.baeldung.eclipsecollections;
+
+import java.util.List;
+
+import org.eclipse.collections.api.list.MutableList;
+import org.eclipse.collections.impl.set.mutable.UnifiedSet;
+
+public class ConvertContainerToAnother {
+
+    @SuppressWarnings("rawtypes")
+    public static List convertToList() {
+        UnifiedSet<String> cars = new UnifiedSet<>();
+
+        cars.add("Toyota");
+        cars.add("Mercedes");
+        cars.add("Volkswagen");
+
+        return cars.toList();
+    }
+}

libraries/src/main/java/com/baeldung/eclipsecollections/Student.java

@@ -0,0 +1,20 @@
+package com.baeldung.eclipsecollections;
+
+public class Student {
+
+    private String firstName;
+    private String lastName;
+
+    public Student(String firstName, String lastName) {
+        this.firstName = firstName;
+        this.lastName = lastName;
+    }
+
+    public String getFirstName() {
+        return this.firstName;
+    }
+
+    public String getLastName() {
+        return this.lastName;
+    }
+}

libraries/src/test/java/com/baeldung/eclipsecollections/AllSatisfyPatternTest.java

@@ -0,0 +1,28 @@
+package com.baeldung.eclipsecollections;
+
+import static org.junit.Assert.assertTrue;
+
+import org.eclipse.collections.api.list.MutableList;
+import org.eclipse.collections.impl.block.factory.Predicates;
+import org.eclipse.collections.impl.list.mutable.FastList;
+import org.junit.Test;
+
+public class AllSatisfyPatternTest {
+
+    @Test
+    public void whenAnySatisfiesCondition_thenCorrect() {
+        MutableList<Integer> list = new FastList<>();
+        list.add(1);
+        list.add(8);
+        list.add(5);
+        list.add(41);
+        list.add(31);
+        list.add(17);
+        list.add(23);
+        list.add(38);
+
+        boolean result = list.allSatisfy(Predicates.greaterThan(0));
+
+        assertTrue(result);
+    }
+}

libraries/src/test/java/com/baeldung/eclipsecollections/AnySatisfyPatternTest.java

@@ -0,0 +1,28 @@
+package com.baeldung.eclipsecollections;
+
+import static org.junit.Assert.assertTrue;
+
+import org.eclipse.collections.api.list.MutableList;
+import org.eclipse.collections.impl.block.factory.Predicates;
+import org.eclipse.collections.impl.list.mutable.FastList;
+import org.junit.Test;
+
+public class AnySatisfyPatternTest {
+
+    @Test
+    public void whenAnySatisfiesCondition_thenCorrect() {
+        MutableList<Integer> list = new FastList<>();
+        list.add(1);
+        list.add(8);
+        list.add(5);
+        list.add(41);
+        list.add(31);
+        list.add(17);
+        list.add(23);
+        list.add(38);
+
+        boolean result = list.anySatisfy(Predicates.greaterThan(30));
+
+        assertTrue(result);
+    }
+}

libraries/src/test/java/com/baeldung/eclipsecollections/CollectPatternTest.java

@@ -0,0 +1,22 @@
+package com.baeldung.eclipsecollections;
+
+import org.eclipse.collections.api.list.MutableList;
+import org.eclipse.collections.impl.list.mutable.FastList;
+import static org.junit.Assert.assertEquals;
+import org.junit.Test;
+
+public class CollectPatternTest {
+
+    @Test
+    public void whenCollect_thenCorrect() {
+        Student student1 = new Student("John", "Hopkins");
+        Student student2 = new Student("George", "Adams");
+
+        MutableList<Student> students = FastList.newListWith(student1, student2);
+
+        MutableList<String> lastNames = students.collect(Student::getLastName);
+
+        assertEquals(lastNames.get(0), "Hopkins");
+        assertEquals(lastNames.get(1), "Adams");
+    }
+}

libraries/src/test/java/com/baeldung/eclipsecollections/ConvertContainerToAnotherTest.java

@@ -0,0 +1,19 @@
+package com.baeldung.eclipsecollections;
+
+import static org.junit.Assert.assertTrue;
+
+import org.eclipse.collections.api.list.MutableList;
+import org.eclipse.collections.impl.block.factory.Predicates;
+import org.junit.Test;
+
+public class ConvertContainerToAnotherTest {
+
+    @SuppressWarnings({ "unchecked", "rawtypes" })
+    @Test
+    public void whenConvertContainerToAnother_thenCorrect() {
+        MutableList<String> cars = (MutableList) ConvertContainerToAnother.convertToList();
+        assertTrue(cars.anySatisfy(Predicates.equal("Toyota")));
+        assertTrue(cars.anySatisfy(Predicates.equal("Mercedes")));
+        assertTrue(cars.anySatisfy(Predicates.equal("Volkswagen")));
+    }
+}

libraries/src/test/java/com/baeldung/eclipsecollections/DetectPatternTest.java

@@ -0,0 +1,27 @@
+package com.baeldung.eclipsecollections;
+
+import org.eclipse.collections.api.list.MutableList;
+import org.eclipse.collections.impl.block.factory.Predicates;
+import org.eclipse.collections.impl.list.mutable.FastList;
+import static org.junit.Assert.assertEquals;
+import org.junit.Test;
+
+public class DetectPatternTest {
+
+    @Test
+    public void whenDetect_thenCorrect() {
+        MutableList<Integer> list = new FastList<>();
+        list.add(1);
+        list.add(8);
+        list.add(5);
+        list.add(41);
+        list.add(31);
+        list.add(17);
+        list.add(23);
+        list.add(38);
+
+        Integer result = list.detect(Predicates.greaterThan(30));
+
+        assertEquals((int) result, 41);
+    }
+}

libraries/src/test/java/com/baeldung/eclipsecollections/ForEachPatternTest.java

@@ -0,0 +1,32 @@
+package com.baeldung.eclipsecollections;
+
+import org.eclipse.collections.api.block.procedure.Procedure;
+import org.eclipse.collections.api.tuple.Pair;
+import org.eclipse.collections.impl.map.mutable.UnifiedMap;
+import org.eclipse.collections.impl.tuple.Tuples;
+import static org.junit.Assert.assertEquals;
+
+import java.util.Map;
+
+import org.junit.Test;
+
+public class ForEachPatternTest {
+
+    @SuppressWarnings("unchecked")
+    @Test
+    public void whenInstantiateAndChangeValues_thenCorrect() {
+        Pair<Integer, String> pair1 = Tuples.pair(1, "One");
+        Pair<Integer, String> pair2 = Tuples.pair(2, "Two");
+        Pair<Integer, String> pair3 = Tuples.pair(3, "Three");
+
+        UnifiedMap<Integer, String> map = UnifiedMap.newMapWith(pair1, pair2, pair3);
+
+        for (int i = 0; i < map.size(); i++) {
+            map.put(i + 1, "New Value");
+        }
+
+        for (int i = 0; i < map.size(); i++) {
+            assertEquals("New Value", map.get(i + 1));
+        }
+    }
+}

libraries/src/test/java/com/baeldung/eclipsecollections/InjectIntoPatternTest.java

@@ -0,0 +1,23 @@
+package com.baeldung.eclipsecollections;
+
+import static org.junit.Assert.assertEquals;
+
+import java.util.List;
+
+import org.eclipse.collections.impl.factory.Lists;
+import org.junit.Test;
+
+public class InjectIntoPatternTest {
+
+    @Test
+    public void whenInjectInto_thenCorrect() {
+        List<Integer> list = Lists.mutable.of(1, 2, 3, 4);
+        int result = 5;
+        for (int i = 0; i < list.size(); i++) {
+            Integer v = list.get(i);
+            result = result + v.intValue();
+        }
+        
+        assertEquals(15, result);
+    }
+}

libraries/src/test/java/com/baeldung/eclipsecollections/LazyIterationTest.java

@@ -0,0 +1,26 @@
+package com.baeldung.eclipsecollections;
+
+import org.eclipse.collections.api.LazyIterable;
+import org.eclipse.collections.api.list.MutableList;
+import org.eclipse.collections.impl.block.factory.Predicates;
+import org.eclipse.collections.impl.factory.Lists;
+import static org.junit.Assert.assertTrue;
+import org.junit.Test;
+
+public class LazyIterationTest {
+
+    @Test
+    public void whenLazyIteration_thenCorrect() {
+        Student student1 = new Student("John", "Hopkins");
+        Student student2 = new Student("George", "Adams");
+        Student student3 = new Student("Jennifer", "Rodriguez");
+
+        MutableList<Student> students = Lists.mutable.with(student1, student2, student3);
+        LazyIterable<Student> lazyStudents = students.asLazy();
+        LazyIterable<String> lastNames = lazyStudents.collect(Student::getLastName);
+
+        assertTrue(lastNames.anySatisfy(Predicates.equal("Hopkins")));
+        assertTrue(lastNames.anySatisfy(Predicates.equal("Adams")));
+        assertTrue(lastNames.anySatisfy(Predicates.equal("Rodriguez")));
+    }
+}

libraries/src/test/java/com/baeldung/eclipsecollections/RejectPatternTest.java

@@ -0,0 +1,32 @@
+package com.baeldung.eclipsecollections;
+
+import org.eclipse.collections.api.list.MutableList;
+import org.eclipse.collections.impl.block.factory.Predicates;
+import org.eclipse.collections.impl.list.mutable.FastList;
+import org.junit.Assert;
+import org.junit.Test;
+
+public class RejectPatternTest {
+
+    @Test
+    public void whenReject_thenCorrect() {
+        MutableList<Integer> list = new FastList<>();
+        list.add(1);
+        list.add(8);
+        list.add(5);
+        list.add(41);
+        list.add(31);
+        list.add(17);
+        list.add(23);
+        list.add(38);
+
+        MutableList<Integer> notGreaterThanThirty = list.reject(Predicates.greaterThan(30))
+            .sortThis();
+
+        Assert.assertEquals(1, (int) notGreaterThanThirty.getFirst());
+        Assert.assertEquals(5, (int) notGreaterThanThirty.get(1));
+        Assert.assertEquals(8, (int) notGreaterThanThirty.get(2));
+        Assert.assertEquals(17, (int) notGreaterThanThirty.get(3));
+        Assert.assertEquals(23, (int) notGreaterThanThirty.getLast());
+    }
+}

libraries/src/test/java/com/baeldung/eclipsecollections/SelectPatternTest.java

@@ -0,0 +1,54 @@
+package com.baeldung.eclipsecollections;
+
+import org.eclipse.collections.api.list.MutableList;
+import org.eclipse.collections.impl.block.factory.Predicates;
+import org.eclipse.collections.impl.list.mutable.FastList;
+import org.junit.Assert;
+import org.junit.Test;
+
+public class SelectPatternTest {
+
+    @Test
+    public void whenSelect_thenCorrect() {
+        MutableList<Integer> list = new FastList<>();
+        list.add(1);
+        list.add(8);
+        list.add(5);
+        list.add(41);
+        list.add(31);
+        list.add(17);
+        list.add(23);
+        list.add(38);
+
+        MutableList<Integer> greaterThanThirty = list.select(Predicates.greaterThan(30))
+            .sortThis();
+
+        Assert.assertEquals(31, (int) greaterThanThirty.getFirst());
+        Assert.assertEquals(38, (int) greaterThanThirty.get(1));
+        Assert.assertEquals(41, (int) greaterThanThirty.getLast());
+    }
+
+    public MutableList selectUsingLambda() {
+        MutableList<Integer> list = new FastList<>();
+        list.add(1);
+        list.add(8);
+        list.add(5);
+        list.add(41);
+        list.add(31);
+        list.add(17);
+        list.add(23);
+        list.add(38);
+
+        return list.select(each -> each > 30)
+            .sortThis();
+    }
+
+    @Test
+    public void whenSelectUsingLambda_thenCorrect() {
+        MutableList<Integer> greaterThanThirty = selectUsingLambda();
+
+        Assert.assertEquals(31, (int) greaterThanThirty.getFirst());
+        Assert.assertEquals(38, (int) greaterThanThirty.get(1));
+        Assert.assertEquals(41, (int) greaterThanThirty.getLast());
+    }
+}