code: public String readHeader()
          throws IOException
      {
          int tag = read();
  
          if (tag == 'H') {
              _isLastChunk = true;
              _chunkLength = (read() << 8) + read();
  
              _sbuf.setLength(0);
              int ch;
              while ((ch = parseChar()) >= 0)
                  _sbuf.append((char) ch);
  
              return _sbuf.toString();
          }
  
          _peek = tag;
  
          return null;
      }
docs: Reads a header, returning null if there are no headers.
  
  <pre>
  H b16 b8 value
  </pre>