Question

用java程序编写

创建一个TreeSet对象，并自其中添加一些员工对象，其姓名和工资分别为：张三 1000，李四 2000，王五 3000，马六 4000，最后按照工资的多少进行降序输出（让Employee对象实现Comparable接口）

Answer 1

import java.util.*;
public class Employee implements Comparable<Employee>{
    private String name;
    private double salary;
    public Employee(String name, double salary){
        this.name = name;
        this.salary = salary;
    }
    public int compareTo(Employee emp){
        if(emp.salary > salary){
            return 1;
        }else if(emp.salary < salary){
            return -1;
        }else {
            return 0;
        }
    }
    public String toString(){
        return String.format("Employee[name=%s, salary=%.2f]", name, salary);
    }
    public static void main(String[] args){
        Employee[] emps = new Employee[]{
            new Employee("张三", 1000),
            new Employee("李四", 2000),
            new Employee("王五", 3000),
            new Employee("马六", 4000)
        };
        System.out.println("排序前：" + Arrays.toString(emps));
        Arrays.sort(emps);
        System.out.println("排序后：" + Arrays.toString(emps));
    }
}