Add switch to set and clear bit

Author: patrickfav

src/main/java/at/favre/lib/bytes/Bytes.java

@@ -690,7 +690,7 @@ public Bytes resize(int newByteLength) {
     }
 
     /**
-     * Returns a Byte whose value is equivalent to this Byte with the designated bit switched to newBitValue. Bits start to count from the LSB (ie. Bytes.from(0).switchBit(0,true) == 1)
+     * Returns a Byte whose value is equivalent to this Byte with the designated bit set to newBitValue. Bits start to count from the LSB (ie. Bytes.from(0).switchBit(0,true) == 1)
      *
      * @param bitPosition not to confuse with byte position
      * @param newBitValue if true set to 1, 0 otherwise
@@ -700,6 +700,16 @@ public Bytes switchBit(int bitPosition, boolean newBitValue) {
         return transform(new BytesTransformer.BitSwitchTransformer(bitPosition, newBitValue));
     }
 
+    /**
+     * Returns a Byte whose value is equivalent to this Byte with the designated bit switched.
+     *
+     * @param bitPosition not to confuse with byte position
+     * @return instance with bit switched
+     */
+    public Bytes switchBit(int bitPosition) {
+        return transform(new BytesTransformer.BitSwitchTransformer(bitPosition, null));
+    }
+
     /**
      * Generic transformation of this instance.
      * <p>

src/main/java/at/favre/lib/bytes/BytesTransformer.java

@@ -290,9 +290,9 @@ public byte[] transform(byte[] currentArray, boolean inPlace) {
      */
     class BitSwitchTransformer implements BytesTransformer {
         private final int position;
-        private final boolean newBitValue;
+        private final Boolean newBitValue;
 
-        BitSwitchTransformer(int position, boolean newBitValue) {
+        BitSwitchTransformer(int position, Boolean newBitValue) {
             this.position = position;
             this.newBitValue = newBitValue;
         }
@@ -307,8 +307,10 @@ public byte[] transform(byte[] currentArray, boolean inPlace) {
 
 
             int bytePosition = currentArray.length - 1 - position / 8;
-            if (newBitValue) {
+            if (newBitValue == null) {
                 out[bytePosition] ^= (1 << position % 8);
+            } else if (newBitValue) {
+                out[bytePosition] |= (1 << position % 8);
             } else {
                 out[bytePosition] &= ~(1 << position % 8);
             }

src/test/java/at/favre/lib/bytes/BytesTransformTest.java

@@ -249,8 +249,11 @@ public void bitSwitch() throws Exception {
         for (int i = 0; i < 63; i++) {
             for (long j = 1; j < 33; j++) {
                 assertEquals("bit position " + i + " is wrong",
-                        BigInteger.valueOf(j).flipBit(i).longValue(),
+                        BigInteger.valueOf(j).setBit(i).longValue(),
                         Bytes.from(j).switchBit(i, true).toLong());
+                assertEquals("bit position " + i + " is wrong",
+                        BigInteger.valueOf(j).flipBit(i).longValue(),
+                        Bytes.from(j).switchBit(i).toLong());
                 assertEquals("bit position " + i + " is wrong",
                         BigInteger.valueOf(j).clearBit(i).longValue(),
                         Bytes.from(j).switchBit(i, false).toLong());