BAEL-7453 - Convert byte[] to Byte[] and Vice Versa in Java

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

@@ -0,0 +1,38 @@
+package com.baeldung.array.conversions;
+
+import org.apache.commons.lang3.ArrayUtils;
+import org.assertj.core.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+class ByteArrayToPrimitiveByteArrayUnitTest {
+    public static byte[] expectedArrayValues = {65, 66, 67, 68};
+    public static Byte[] byteArray = {65, 66, 67, 68};
+
+    @Test
+    void givenByteArray_whenConvertingUsingByteValue_thenGiveExpectedResult() {
+        byte[] newByteArray = new byte[byteArray.length];
+        for (int i = 0; i < byteArray.length; i++) {
+            newByteArray[i] = byteArray[i].byteValue();
+        }
+        Assertions.assertThat(newByteArray)
+          .containsExactly(expectedArrayValues);
+    }
+
+    @Test
+    void givenByteArray_whenConvertingUsingUnboxing_thenGiveExpectedResult() {
+        byte[] newByteArray = new byte[byteArray.length];
+        for (int i = 0; i < byteArray.length; i++) {
+            newByteArray[i] = byteArray[i];
+        }
+        Assertions.assertThat(newByteArray)
+          .containsExactly(expectedArrayValues);
+    }
+
+    @Test
+    void givenByteArray_whenConvertingArrayUtils_thenGiveExpectedResult() {
+        byte[] newByteArray = ArrayUtils.toPrimitive(byteArray);
+
+        Assertions.assertThat(newByteArray)
+          .containsExactly(expectedArrayValues);
+    }
+}

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

@@ -0,0 +1,49 @@
+package com.baeldung.array.conversions;
+
+import java.util.Arrays;
+
+import org.apache.commons.lang3.ArrayUtils;
+import org.assertj.core.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+class PrimitiveByteArrayToByteArrayUnitTest {
+    public static byte[] primitiveByteArray = {65, 66, 67, 68};
+    public static Byte[] expectedArrayValues = {65, 66, 67, 68};
+
+    @Test
+    void givenPrimitiveByteArray_whenConvertingUsingByteValueOf_thenGiveExpectedResult() {
+        Byte[] newByteArray = new Byte[primitiveByteArray.length];
+        for (int i = 0; i < primitiveByteArray.length; i++) {
+            newByteArray[i] = Byte.valueOf(primitiveByteArray[i]);
+        }
+        Assertions.assertThat(newByteArray)
+          .containsExactly(expectedArrayValues);
+    }
+
+    @Test
+    void givenPrimitiveByteArray_whenConvertingUsingAutoboxing_thenGiveExpectedResult() {
+        Byte[] newByteArray = new Byte[primitiveByteArray.length];
+        for (int i = 0; i < primitiveByteArray.length; i++) {
+            newByteArray[i] = primitiveByteArray[i];
+        }
+        Assertions.assertThat(newByteArray)
+            .containsExactly(expectedArrayValues);
+    }
+
+    @Test
+    void givenPrimitiveByteArray_whenConvertingUsingAutoboxingAndArraysSetAll_thenGiveExpectedResult() {
+        Byte[] newByteArray = new Byte[primitiveByteArray.length];
+        Arrays.setAll(newByteArray, n -> primitiveByteArray[n]);
+
+        Assertions.assertThat(newByteArray)
+            .containsExactly(expectedArrayValues);
+    }
+
+    @Test
+    void givenPrimitiveByteArray_whenConvertingUsingArrayUtils_thenGiveExpectedResult() {
+        Byte[] newByteArray = ArrayUtils.toObject(primitiveByteArray);
+
+        Assertions.assertThat(newByteArray)
+            .containsExactly(expectedArrayValues);
+    }
+}