java抽象类继承

抽象类

public abstract class Abstract {
    public String name;
    private int age;
    Abstract(){};
    public Abstract(String myname,int myage){
        this.name=myname;
        this.age=myage;
    }
    public void out(){
        System.out.println("这是抽象类，不能直接实例化"+name+" "+age);
    }
    public void out(String name){
        System.out.println("这是抽象类，不能直接实例化"+name+" "+age);
    }
}
class abs extends Abstract{

    public abs(String myname, int myage) {
        super(myname, myage);
    }
    public void out(){
        System.out.println("子类");
    }
    public static void main(String[] args) {
        new Abstract():
    //    abs a=new abs("hadoop",18);
//        Abstract b=new abs("hive",19);
//        a.out();
//        b.out();
//        a.out("mysql");
//        b.out("sqoop");
    }

}

因为抽象类不能直接被实例化，这里运行会报错

用子类继承后，就可以通过子类来调用父类方法

    public static void main(String[] args) {
//        new Abstract():
        abs a=new abs("hadoop",18);
        Abstract b=new abs("hive",19);
        a.out();
        b.out();
        a.out("mysql");
        b.out("sqoop");
    }