code: public static void _idx(final byte[] array, int startIndex, byte[] input) {
  		try {
  
  			System.arraycopy(input, 0, array, startIndex, input.length);
  		} catch (Exception ex) {
  			throw new KriptonRuntimeException(String.format("array size %d, startIndex %d, input length %d", array.length, startIndex, input.length), ex);
  		}
  	}
docs: Idx.
  
  @param array the array
  @param startIndex the start index
  @param input the input