抽象类

由于抽象类不能实例化对象，所以抽象类必须被继承，才能被使用。

 1 package test1;
 2 
 3 public class Main
 4 {
 5     public static void main(String[] args)
 6     {
 7         //此时会引发报错
 8         Father f=new Father("张三",30);
 9         System.out.println(f.toString());
10     }
11 }
 1 package test1;
 2 
 3 public abstract class Father
 4 {
 5     private String name;
 6     private int age;
 7     public Father()
 8     {
 9         super();
10     }
11     public Father(String name, int age)
12     {
13         super();
14         this.name = name;
15         this.age = age;
16     }
17     @Override
18     public String toString() 
19     {
20         return "Father [name=" + name + ", age=" + age + "]";
21     }    
22 }

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 1 package test1;
 2 
 3 public class Main
 4 {
 5     public static void main(String[] args)
 6     {
 7         //此时会运行成功
 8         Son s=new Son("张三",30);
 9         System.out.println(s.toString());
10     }
11 }
 1 package test1;
 2 
 3 public abstract class Father
 4 {
 5     private String name;
 6     private int age;
 7     public Father()
 8     {
 9         super();
10     }
11     public Father(String name, int age)
12     {
13         super();
14         this.name = name;
15         this.age = age;
16     }
17     @Override
18     public String toString() 
19     {
20         return "Father [name=" + name + ", age=" + age + "]";
21     }    
22 }
1 package test1;
2 
3 public class Son extends Father
4 {
5     public Son(String name,int age)//定自己的构造方法
6     {
7         super(name,age);//调用父类的构造方法
8     }
9 }

 

posted @ 2016-12-08 10:23  明天会更好！！！！  阅读(127)  评论(0)    收藏  举报