获取类的有关信息

import java.lang.reflect.*;

 

class Rect

{

double width,height,area;

public double getArea()

{

  area=width*height;

  return area;

}

}

public class hello {

public static void main(String[] args) 

{

// TODO Auto-generated method stub

Rect rect=new Rect();

Class cs=rect.getClass();

String classname=cs.getName();

Constructor[] cons=cs.getDeclaredConstructors();

Field[] fields=cs.getDeclaredFields();

Method[] methods=cs.getDeclaredMethods();

System.out.println("类名是："+classname);

System.out.println("/n构造函数是：");

for(int i=0;i<cons.length;i++)

{

System.out.println("/n"+cons[i].toString());

}

System.out.println("/n成员变量：");

for(int i=0;i<fields.length;i++)

{

System.out.println("/n"+fields[i].toString());

}

System.out.println("/n方法：");

for(int i=0;i<methods.length;i++)

{

System.out.println("/n"+methods[i].toString());

}

}

}