private static byte[] incrementAtIndex(final byte[] bytes,final int index){
  final byte[] copy=new byte[bytes.length];
  System.arraycopy(bytes,0,copy,0,bytes.length);
  ++copy[index];
  return copy;
}

private static byte [ ] incrementAtIndex ( final byte [ ] bytes , final int index ) { final byte [ ] copy = new byte [ bytes . length ] ; System . arraycopy ( bytes , 0 , copy , 0 , bytes . length ) ; ++ copy [ index ] ; return copy ; }
increments a single byte in the specified byte array .
