code: @Override
      protected void _releaseBuffers()
              throws IOException
      {
          super._releaseBuffers();
          char[] buf = _inputBuffer;
          if (buf != null) {
              _inputBuffer = null;
              _ioContext.releaseTokenBuffer(buf);
          }
      }
docs: Method called to release internal buffers owned by the base
  reader. This may be called along with {@link #_closeInput} (for
  example, when explicitly closing this reader instance), or
  separately (if need be).