java 面向对象中的多态与继承

objectj.java:

public class objectj {
    private String name;
    private String address;
    private int number;

    public objectj(String name, String address, int number) {
        this.name = name;
        this.address = address;
        this.number = number;
    };

    public void mailcheck() {
        System.out.println("send mail to:" + this.name + "address: " + this.address);

    };

    public void promise() {
        System.out.println("pass!");
    };

    public String getname() {
        return this.name;
    };

    public String getaddress() {
        return this.address;
    }
};

salary.java:

import java.io.*;

import javax.security.auth.Subject;

public class salary extends objectj {
    private double sala;

    public salary(String name, String address, int number, double sal) {
        super(name, address, number);
        this.sala = sal;
    }

    public void mailcheck() {
        System.out.println("salary:");
        System.out.println("send mail to:" + getname() + "address: " + getaddress());

    };

    public void computepay() {
        System.out.println("computepay to :" + getname() + "  salary: " + this.sala);
    }

}

testdemo.java:

public class testdemo {

    public static void main(String[] args) {
        objectj obj = new salary("zhangsan", "beijing", 1, 8900);
        salary obj1 = new salary("lisi", "shanghai", 2, 9234.1);
        obj.mailcheck();
        obj1.mailcheck();
        obj1.promise();
        obj1.computepay();
    }

}

输出：

salary:
send mail to:zhangsanaddress: beijing
salary:
send mail to:lisiaddress: shanghai
pass!
computepay to :lisi  salary: 9234.1