如何将荧光笔插入JFreeChart？

Question

我正在使用PeakFind算法从数组中查找峰值（最大值）。
我在控制台上得到了结果。我想要一些荧光笔在JFreeChart上显示。
任何人都可以帮助我吗？

以下是peak_finder的代码

public class PeakAlgorithm 
{
   static double[] xArray;
   static double[] yArray;

   static double[] derivative;


   public static void peak_Algorithm(double[] x,double[] y)
  {
      xArray=new double[x.length];
      yArray=new double[y.length];

      xArray=x;
      yArray=y;


      derivative=new double[xArray.length-1];
      derivative=derivativeXY(xArray,yArray);


      for(int i=0;i<derivative.length-1;i++)
      {
          if((sign(derivative[i])>(sign(derivative[i+1])))&derivative[i]>0.5)
                {
                   System.out.println(xArray[i]+" "+yArray[i]);
                 }
            }

         }
           public static int sign(double derivative2) 
    {
        int result=0;
        if (derivative2 != derivative2) 
        if (derivative2 == 0) 
        result= 0;
        derivative2 *= Double.POSITIVE_INFINITY;
        if (derivative2 == Double.POSITIVE_INFINITY) 
        result=1;
        if (derivative2 == Double.NEGATIVE_INFINITY) 
        result=-1;

       return result;
    }

     public static double[] derivativeXY(double[] x,double[] y)
    {
       derivative=new double[x.length-1];
       for (int j=1;j<derivative.length-1;j++)
      {
        derivative[j]=(y[j+1]-y[j-1]) / ((x[j+1]-x[j-1]));
      }
       return derivative;
   }
   }