BAEL-6831: Convert an int[] Array to HashSet in Java (#14525)

Co-authored-by: Tapan Avasthi <tavasthi@Tapans-MacBook-Air.local>

core-java-modules/core-java-arrays-convert/src/test/java/com/baeldung/array/conversions/PrimitiveIntArrayToHashSetUnitTest.java

@@ -0,0 +1,53 @@
+package com.baeldung.array.conversions;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotEquals;
+
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.stream.Collectors;
+
+import org.apache.commons.lang3.ArrayUtils;
+import org.junit.Test;
+
+import com.google.common.primitives.Ints;
+
+public class PrimitiveIntArrayToHashSetUnitTest {
+    int[] arr = { 1, 2, 3, 4, 5 };
+    HashSet<Integer> expected = new HashSet<>(Arrays.asList(1, 2, 3, 4, 5));
+
+    @Test
+    public void givenPrimitiveIntArray_whenConvertingByDirectConstructor_thenGiveWrongResult() {
+        HashSet<int[]> result = new HashSet<>(Arrays.asList(arr));
+        assertEquals(1, result.size());
+        assertNotEquals(expected, result);
+    }
+
+    @Test
+    public void givenPrimitiveIntArray_whenConvertingByLoop_thenSuccess() {
+        HashSet<Integer> result = new HashSet<>();
+        for (int num : arr) {
+            result.add(num);
+        }
+        assertEquals(expected, result);
+    }
+
+    @Test
+    public void givenPrimitiveIntArray_whenConvertingByStreams_thenSuccess() {
+        HashSet<Integer> result = Arrays.stream(arr).boxed().collect(Collectors.toCollection(HashSet::new));
+        assertEquals(expected, result);
+    }
+
+    @Test
+    public void givenPrimitiveIntArray_whenConvertingByArrayUtils_thenSuccess() {
+        HashSet<Integer> result = new HashSet<>(Arrays.asList(ArrayUtils.toObject(arr)));
+        assertEquals(expected, result);
+    }
+
+    @Test
+    public void givenPrimitiveIntArray_whenConvertingByGuava_thenSuccess() {
+        HashSet<Integer> result = new HashSet<>(Ints.asList(arr));
+        assertEquals(expected, result);
+    }
+
+}