10.15习题2

package com.Hanqi2;

public class _1 
{
    
    public _1()
    {
        
    }
    public String xingming;
    
    public String renzhong;
    
    public int age;
    
    public _1(String xingming, String renzhong,int age)
    {
        System.out.println(xingming + "是一个" + renzhong + "," + age + "岁了");
    }

    //成长
    public void chengzhang(int chengzhang)
    {
        age += chengzhang;
        System.out.println(chengzhang + "年后他" + age + "岁了");
        
    }

    

    
}

package com.Hanqi2;

public class _2 extends _1{

    public _2(String xingming,String renzhong,int age)
    {
        super(xingming,renzhong,age);
    }
    
    public _2()
    {
        
    }
    

    
    public void chengzhang(int grew)
    {
        age += grew;
        System.out.println(grew + "yeas ago,he is " + age);
        
    }
}

package com.Hanqi2;

public class _3 {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        
        _1 body = new _1("mading","白种人",25);
        
        body.age = 25;
        body.chengzhang(9);
        
        _1 b1 = new _2();
        
        b1.age = 15;
        b1.chengzhang(1);
        
        
    }

}

结果为 :

mading是一个白种人,25岁了
9年后他34岁了
1yeas ago,he is 16