父類

package com.imooc;

public abstract class Shape {

public abstract void zhouchang();

public abstract void mianji();

public int a=3,b=2,c=(a+b)*2,d=a*b;

double π=3.14;

int r=3;

double e=2*r*π;

double s=r*r*π;

}

子類

package com.imooc;

public class Circle extends Shape {

@Override

public void zhouchang() {

// TODO Auto-generated method stub

System.out.println("圓的周長"+e);

}

@Override

public void mianji() {

// TODO Auto-generated method stub

System.out.println("圓的面積"+s);

}

}

子類

package com.imooc;

public class Rectangle extends Shape {

@Override

public void zhouchang() {

// TODO Auto-generated method stub

System.out.println("矩形的周長"+c);

}

@Override

public void mianji() {

// TODO Auto-generated method stub

System.out.println("矩形的面積"+d);

}

}

測試

package com.imooc;

public class Initail {

public static void main(String[] args) {

// TODO Auto-generated method stub

Shape abc=new Rectangle();

abc.zhouchang();

abc.mianji();

Shape ab=new Circle();

ab.zhouchang();

ab.mianji();

}

}