code: public long skip(long len) throws IOException
      { 
          if (_chunkSize<=0 && getChunkSize()<=0)
                  return -1;
          if (len > _chunkSize)
              len=_chunkSize;
          len=_in.skip(len);
          if (len<0)
          {
              _chunkSize=-1;
              throw new IOException(__UNEXPECTED_EOF);
          }
          _chunkSize=_chunkSize-(int)len;
          return len;
      }
docs: /* ------------------------------------------------------------