methodpointertest.java

来自「JAVA继承的例子」· Java 代码 · 共 38 行

import java.lang.reflect.*;

public class MethodPointerTest
{
    public static void main(String[] args) throws Exception
    {
        Method square=MethodPointerTest.class.getMethod("square",double.class);
        Method sqrt=Math.class.getMethod("sqrt",double.class);
        
        printTable(1,10,10,square);
        printTable(1,10,10,sqrt);
    }
    
    public static double square(double x)
    {
        return x*x;
    }
    
    public static void printTable(double from,double to,int n,Method f)
    {
        System.out.println(f);
        
        double dx=(to-from)/(n-1);
        
        for(double x=from;x<=to;x+=dx)
        {
            try
            {
                double y=(Double) f.invoke(null,x);
                System.out.printf("%10.4f|%10.4f%n",x,y);
            }
            catch(Exception e)
            {
                e.printStackTrace();
            }
        }
    }
}