code: public void skipMark() throws IOException {
          dump(new OutputStream() {
              public void write(int b) throws IOException {}
  
              public void close() throws IOException {}
  
              public void flush() throws IOException {}
  
              public void write(byte[] b, int off, int len) throws IOException {}
  
              public void write(byte[] b) throws IOException {}
  
          });
      }
docs: 不输出，直接跳过 Mark，相当于将当前的 Mark dump 到一个空的输出流
  
  @throws IOException