code: public WrappedByteBuffer putBytesAt(int index, byte[] b) {
          _checkForWriteAt(index, b.length);
          int pos = _buf.position();
          _buf.position(index);
          _buf.put(b, 0, b.length);
          _buf.position(pos);
          return this;
      }
docs: Puts a single-byte array into the buffer at the specified index.
  
  @param index the index
  @param v the single-byte array
  
  @return the buffer