Merge pull request #32 from RUB-NDS/ArrayConverter-ReverseByteOrder

added method in ArrayConverter to reverse bytes in an array

Author: ic0ns

src/main/java/de/rub/nds/modifiablevariable/util/ArrayConverter.java

@@ -177,7 +177,7 @@ public static String bytesToHexString(byte[] array, boolean usePrettyPrinting, b
 
     /**
      * Like bytesToHexString() without any formatting.
-     * 
+     *
      * @param array
      *            byte array
      * @return hex string
@@ -401,4 +401,22 @@ public static byte[] longToUint48Bytes(long input) {
 
         return output;
     }
+
+    /**
+     * Reverses the order of a byte array: So, [0x00,0x01,0x02,0x03] will be
+     * returned as [0x03,0x02,0x01,0x00]
+     *
+     * @param array
+     *            the byte array to reverse
+     * @return byte array with reversed byte order
+     */
+    public static byte[] reverseByteOrder(byte[] array) {
+        int length = array.length;
+        byte[] temp = new byte[length];
+        int counter = length - 1;
+        for (int i = 0; i < length; i++) {
+            temp[i] = array[counter--];
+        }
+        return temp;
+    }
 }

src/test/java/de/rub/nds/modifiablevariable/util/ArrayConverterTest.java

@@ -237,4 +237,14 @@ public void testBytesToHexString_ModifiableByteArray() {
                 ArrayConverter.bytesToHexString(toTest));
     }
 
+    /**
+     * Test of reverseByteOrder method, of class ArrayConverter.
+     */
+    @Test
+    public void testReverseByteOrder() {
+        byte[] array = new byte[] { 0x00, 0x01, 0x02, 0x03, 0x04 };
+
+        assertArrayEquals("Testing byte order reversion", new byte[] { 0x04, 0x03, 0x02, 0x01, 0x00 },
+                ArrayConverter.reverseByteOrder(array));
+    }
 }