docs: public String encode() throws IOException {
          FastStringWriter fsw = new FastStringWriter();
  
          try {
              ChartUtils.writeDataValue(fsw, "borderWidth", this.borderWidth, false);
              ChartUtils.writeDataValue(fsw, "backgroundColor", this.backgroundColor, true);
              ChartUtils.writeDataValue(fsw, "borderColor", this.borderColor, true);
          }
          finally {
              fsw.close();
          }
  
          return fsw.toString();
      }