code: public BufferBuilder append(ClientProtocolBuffer srcBuffer, int srcOffset, int length) {
          ensureCapacity(length);
  
          srcBuffer.getBytes(srcOffset, protocolBuffer.byteArray(), position, length);
          position += length;
  
          return this;
      }
docs: Append a source buffer to the end of the internal buffer, resizing the internal buffer as required.
  
  @param srcBuffer from which to copy.
  @param srcOffset in the source buffer from which to copy.
  @param length    in bytes to copy from the source buffer.
  @return the builder for fluent API usage.