docs: public String encode() throws IOException {
          FastStringWriter fsw = new FastStringWriter();
  
          try {
              fsw.write("{");
  
              ChartUtils.writeDataValue(fsw, "display", this.display, false);
              ChartUtils.writeDataValue(fsw, "color", this.color, true);
              ChartUtils.writeDataValue(fsw, "borderDash", this.borderDash, true);
              ChartUtils.writeDataValue(fsw, "borderDashOffset", this.borderDashOffset, true);
              ChartUtils.writeDataValue(fsw, "lineWidth", this.lineWidth, true);
              ChartUtils.writeDataValue(fsw, "drawBorder", this.drawBorder, true);
              ChartUtils.writeDataValue(fsw, "drawOnChartArea", this.drawOnChartArea, true);
              ChartUtils.writeDataValue(fsw, "drawTicks", this.drawTicks, true);
              ChartUtils.writeDataValue(fsw, "tickMarkLength", this.tickMarkLength, true);
              ChartUtils.writeDataValue(fsw, "zeroLineWidth", this.zeroLineWidth, true);
              ChartUtils.writeDataValue(fsw, "zeroLineColor", this.zeroLineColor, true);
              ChartUtils.writeDataValue(fsw, "zeroLineBorderDash", this.zeroLineBorderDash, true);
              ChartUtils.writeDataValue(fsw, "zeroLineBorderDashOffset", this.zeroLineBorderDashOffset, true);
              ChartUtils.writeDataValue(fsw, "offsetGridLines", this.offsetGridLines, true);
  
              fsw.write("}");
          }
          finally {
              fsw.close();
          }
  
          return fsw.toString();
      }