code: public static int putBytes(byte[] tgtBytes, int tgtOffset, byte[] srcBytes,
        int srcOffset, int srcLength) {
      System.arraycopy(srcBytes, srcOffset, tgtBytes, tgtOffset, srcLength);
      return tgtOffset + srcLength;
    }
docs: Put bytes at the specified byte array position.
  @param tgtBytes the byte array
  @param tgtOffset position in the array
  @param srcBytes array to write out
  @param srcOffset source offset
  @param srcLength source length
  @return incremented offset