code: public void setDashedLinePram(double length, double interval) {
          this.dashedLineLength = length;
          this.dashedLineInterval = interval;
          this.dashed = true;
          calcDashedLine();
      }
docs: Sets the parameter for the dashed line.
  
  @param length The length of the dashed lines.
  @param interval The interval of the dashed lines.