java面向对象——继承与方法重写

普通方法的继承
public class Emp {
    String name;
    int age;
    public void work(){
        System.out.println("员工正在工作");
    }
}
//维护部员工继承自员工
public class WeiHu extends Emp{
//自己的方法
    public void speak(){
        System.out.println("我叫"+name);
    }
}
//研发部员工继承自员工
public class Yanfa extends Emp{
    
}



public class Test {
    public static void main(String[] args) {
        Yanfa yf=new Yanfa();
        yf.name="小猪佩奇";
        yf.age=18;
        yf.work();
        WeiHu wh=new WeiHu();
        wh.name="乔治";
        wh.age=18;
        wh.work();
        wh.speak();
    }
}

//方法重写
public class Phone {
    public void show(){
        System.out.println("显示电话号码");
    }
    public void duanxin(){
        System.out.println("发短信");
    }
    public void call(){
        System.out.println("打电话");
    }
}
public class Iphone extends Phone{
    public void show(){
        super.show();
        System.out.println("显示头像");
        System.out.println("显示姓名");
    }
}
public class Test1 {
    public static void main(String[] args) {
        Iphone i=new Iphone();
        i.show();
        i.duanxin();
        i.call();
    }
}
//私有化 方法重写
public class School {
    private String name;
    private int age;
    
    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public void work(){
        System.out.println(name+age);
        System.out.println("吃饭");
    }
}
public class Student extends School{
    public void work(){
        super.work();
        System.out.println("学习");
    }
}
public class Teacher extends School{
    public void work(){
        super.work();
        System.out.println("讲课");
    }
}



public class Test1 {
    public static void main(String[] args) {
        Teacher t=new Teacher();
        t.setName("吴丹");
        t.setAge(18);
        t.work();
        Student s=new Student();
        s.setName("赵涛");
        s.setAge(18);
        s.work();
    }
}
抽象方法的继承与重写  关键字abstract  练习在demo10
public abstract class Developer {
    //抽象方法
    public abstract void work();
    //普通方法
    public void speak(){
        System.out.println("研发部员工开会");
    }
}
public class JavaEE extends Developer{
    public void work(){
        System.out.println("Hello everone");
    }
}
public class Test {
    public static void main(String[] args) {
        JavaEE j=new JavaEE();
        j.work();
        j.speak();
    }
}