Java 抽象类

、

package com.qugeng.jdk;

public class MethodDemo {
    public static void main(String[] args) {
        AbsDemo a = new AbsDemo();
        a.say();
        a.print();
    }
}

abstract class  Abs{
    private int age;
    public void tell(){
    }
    public abstract void say();
    public abstract void print();
}

 /**
  * 子类必须重写父类的方法
  * @author Administrator
  *
  */
 class AbsDemo extends Abs
{
    public void say() {
    }
    public void print(){
        
    }
}
 

package com.qugeng.jdk;

public class MethodDemo {
    public static void main(String[] args) {
        A a = new A();
        a.tell();
        System.out.println();
    }
}

interface Inter2
{
    public abstract  void say();
    
}

abstract class Abs1{
    public abstract void print();
}

interface Inter1{
    
    public static final int AGE = 100;
    public abstract void tell();
}


 class A extends Abs1 implements Inter1,Inter2{
    public void tell(){
        
    }
    public void say()
    {
        
    }
    public void print()
    {
        
    }
}