Java-继承，多态-0922-04

定义类Human，具有若干属性和功能；定义其子类Man、Woman； 在主类Test中分别创建子类、父类和上转型对象，并测试其特性。

父类：

package com.lianxi3;

public class Human {
    private String speak;
    private String jump;
    public String getSpeak() {
        return speak;
    }
    public void setSpeak(String speak) {
        this.speak = speak;
    }
    public String getJump() {
        return jump;
    }
    public void setJump(String jump) {
        this.jump = jump;
    }
    public Human(String speak, String jump) {
        super();
        this.speak = speak;
        this.jump = jump;
    }
    public Human() {
        super();
    }

    public void Jump()
    {
        System.out.println("跳："+jump);
    }
    public void Speak()
    {
        System.out.println("说："+speak);
    }
    public void as()
    {
        System.out.println("我能工作");
    }

}

子类：

package com.lianxi3;

public class Man extends Human {
    private String shui;

    public String getShui() {
        return shui;
    }

    public void setShui(String shui) {
        this.shui = shui;
    }

    public void Shui()
    {
        System.out.println("睡"+shui);
    }

}

测试：

package com.lianxi3;

public class Test {

    public static void main(String[] args) {
        Man m=new Man();
        m.setJump("低");
        m.setShui("长");
        m.setSpeak("粗");
        System.out.println("声音："+m.getSpeak()+" 跳："+m.getJump()+" 睡："+m.getShui());

        //向上转型
        Human h=new Man();
        h.as();  //如果方法被重写，则调用子类的函数

        //向下转型
        Object ob=new Man();//先转形成等级最高的object

        Man ma=(Man)ob;  //在转型所需要的类型

    }

}