Merge pull request #9621 from jesperancinha/BAEL-4281

[BAEL-4281] Examples of array comparisons

core-java-modules/core-java-arrays-operations-advanced/src/main/java/com/baeldung/arraycompare/Plane.java

@@ -0,0 +1,39 @@
+package com.baeldung.arraycompare;
+
+import java.util.Objects;
+
+public class Plane {
+
+    private final String name;
+
+    private final String model;
+
+    public Plane(String name, String model) {
+
+        this.name = name;
+        this.model = model;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public String getModel() {
+        return model;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o)
+            return true;
+        if (o == null || getClass() != o.getClass())
+            return false;
+        Plane plane = (Plane) o;
+        return Objects.equals(name, plane.name) && Objects.equals(model, plane.model);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(name, model);
+    }
+}

core-java-modules/core-java-arrays-operations-advanced/src/test/java/com/baeldung/arraycompare/DeepEqualsCompareUnitTest.java

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+package com.baeldung.arraycompare;
+
+import org.junit.jupiter.api.Test;
+
+import java.util.Arrays;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class DeepEqualsCompareUnitTest {
+
+    @Test
+    public void givenSameContents_whenDeepEquals_thenTrue() {
+        final Plane[][] planes1 = new Plane[][] { new Plane[] { new Plane("Plane 1", "A320") },
+            new Plane[] { new Plane("Plane 2", "B738") } };
+        final Plane[][] planes2 = new Plane[][] { new Plane[] { new Plane("Plane 1", "A320") },
+            new Plane[] { new Plane("Plane 2", "B738") } };
+
+        assertThat(Arrays.deepEquals(planes1, planes2)).isTrue();
+    }
+
+    @Test
+    public void givenSameContentsWithDifferentOrder_whenDeepEquals_thenFalse() {
+        final Plane[][] planes1 = new Plane[][] { new Plane[] { new Plane("Plane 1", "A320") },
+            new Plane[] { new Plane("Plane 2", "B738") } };
+        final Plane[][] planes2 = new Plane[][] { new Plane[] { new Plane("Plane 2", "B738") },
+            new Plane[] { new Plane("Plane 1", "A320") } };
+
+        assertThat(Arrays.deepEquals(planes1, planes2)).isFalse();
+    }
+}

core-java-modules/core-java-arrays-operations-advanced/src/test/java/com/baeldung/arraycompare/EqualsCompareUnitTest.java

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+package com.baeldung.arraycompare;
+
+import org.junit.jupiter.api.Test;
+
+import java.util.Arrays;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class EqualsCompareUnitTest {
+
+    @Test
+    public void givenSameContents_whenEquals_thenTrue() {
+        final String[] planes1 = new String[] { "A320", "B738", "A321", "A319", "B77W", "B737", "A333", "A332" };
+        final String[] planes2 = new String[] { "A320", "B738", "A321", "A319", "B77W", "B737", "A333", "A332" };
+
+        assertThat(Arrays.equals(planes1, planes2)).isTrue();
+    }
+
+    @Test
+    public void givenSameContentsDifferentOrder_whenEquals_thenFalse() {
+        final String[] planes1 = new String[] { "A320", "B738", "A321", "A319", "B77W", "B737", "A333", "A332" };
+        final String[] planes2 = new String[] { "B738", "A320", "A321", "A319", "B77W", "B737", "A333", "A332" };
+
+        assertThat(Arrays.equals(planes1, planes2)).isFalse();
+    }
+}

core-java-modules/core-java-arrays-operations-advanced/src/test/java/com/baeldung/arraycompare/LengthsCompareUnitTest.java

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+package com.baeldung.arraycompare;
+
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class LengthsCompareUnitTest {
+
+    @Test
+    public void givenSameContent_whenSizeCompare_thenTrue() {
+        final String[] planes1 = new String[] { "A320", "B738", "A321", "A319", "B77W", "B737", "A333", "A332" };
+        final Integer[] quantities = new Integer[] { 10, 12, 34, 45, 12, 43, 5, 2 };
+
+        assertThat(planes1).hasSize(8);
+        assertThat(quantities).hasSize(8);
+    }
+}
+

core-java-modules/core-java-arrays-operations-advanced/src/test/java/com/baeldung/arraycompare/OrderCompareUnitTest.java

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+package com.baeldung.arraycompare;
+
+import org.junit.jupiter.api.Test;
+
+import java.util.Arrays;
+import java.util.Comparator;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.Assert.assertTrue;
+
+public class OrderCompareUnitTest {
+    @Test
+    public void givenSameContentDifferentOrder_whenSortedAndDeepEquals_thenTrue() {
+        final Plane[][] planes1 = new Plane[][] {
+            new Plane[] { new Plane("Plane 1", "A320"), new Plane("Plane 2", "B738") } };
+        final Plane[][] planes2 = new Plane[][] {
+            new Plane[] { new Plane("Plane 2", "B738"), new Plane("Plane 1", "A320") } };
+
+        Comparator<Plane> planeComparator = (o1, o2) -> {
+            if (o1.getName()
+                .equals(o2.getName())) {
+                return o2.getModel()
+                    .compareTo(o1.getModel());
+            }
+            return o2.getName()
+                .compareTo(o1.getName());
+        };
+        Arrays.sort(planes1[0], planeComparator);
+        Arrays.sort(planes2[0], planeComparator);
+
+        assertThat(Arrays.deepEquals(planes1, planes2)).isTrue();
+    }
+}

core-java-modules/core-java-arrays-operations-advanced/src/test/java/com/baeldung/arraycompare/ReferenceCompareUnitTest.java

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+package com.baeldung.arraycompare;
+
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class ReferenceCompareUnitTest {
+
+    @Test
+    public void givenSameReferences_whenSame_thenTrue() {
+        final String[] planes1 = new String[] { "A320", "B738", "A321", "A319", "B77W", "B737", "A333", "A332" };
+        final String[] planes2 = planes1;
+
+        assertThat(planes1).isSameAs(planes2);
+
+        planes2[0] = "747";
+
+        assertThat(planes1).isSameAs(planes2);
+        assertThat(planes2[0]).isEqualTo("747");
+        assertThat(planes1[0]).isEqualTo("747");
+    }
+
+    @Test
+    public void givenSameContentDifferentReferences_whenSame_thenFalse() {
+        final String[] planes1 = new String[] { "A320", "B738", "A321", "A319", "B77W", "B737", "A333", "A332" };
+        final String[] planes2 = new String[] { "A320", "B738", "A321", "A319", "B77W", "B737", "A333", "A332" };
+
+        assertThat(planes1).isNotSameAs(planes2);
+    }
+}