code: public WrappedByteBuffer fillWith(byte b, int size) {
          _autoExpand(size);
          while (size-- > 0) {
              _buf.put(b);
          }
          return this;
      }
docs: Fills the buffer with a specific number of repeated bytes.
  
  @param b
  the byte to repeat
  @param size
  the number of times to repeat
  
  @return the buffer