Use TreeMap and Comparable compare

package com.mengge.test;

import java.util.Map;
import java.util.TreeMap;;

public class TestTreeMap {
    
    public static void main(String[] args) {
//      Map<Integer, String> myMap = new TreeMap<Integer, String>();
        
//      Map<Integer, String> map = new java.util.TreeMap<>();
//              
//      map.put(1, "列宁");
//      map.put(3, "斯达克");
//      map.put(100, "时代大厦");
//      map.put(22, "阿斯达");
//      map.put(88, "uuuiw");
//      
//      for (Integer keyIndex : map.keySet()) {
//          System.out.println("key:" + keyIndex + ", value:" + map.get(keyIndex));
//      }

        
        MyEmployee mye1 = new MyEmployee(10, "张三", 1000);
        MyEmployee mye2 = new MyEmployee(90, "李四", 90000);
        MyEmployee mye3 = new MyEmployee(20, "王五", 3000);
        MyEmployee mye4 = new MyEmployee(30, "赵六", 3000);
        MyEmployee mye5 = new MyEmployee(900, "王五", 9000);
        MyEmployee mye6 = new MyEmployee(80, "王七", 7000);
        MyEmployee mye7 = new MyEmployee(22, "王八", 90000);
        MyEmployee mye8 = new MyEmployee(9, "王九", 1000);

        Map<MyEmployee, Integer> objectMap = new TreeMap<MyEmployee, Integer>();
        objectMap.put(mye1, mye1.getNid());
        objectMap.put(mye2, mye2.getNid());
        objectMap.put(mye3, mye3.getNid());
        objectMap.put(mye4, mye4.getNid());
        objectMap.put(mye5, mye5.getNid());
        objectMap.put(mye6, mye6.getNid());
        objectMap.put(mye7, mye7.getNid());
        objectMap.put(mye8, mye8.getNid());
        
        
        for (MyEmployee emp : objectMap.keySet()) {
            System.out.println("姓名:" + emp.getName() + ", 薪资:" + emp.getSalary() + ", id:" + emp.getNid());
        }
        
        
        
    }

}


class MyEmployee implements Comparable<MyEmployee> {
    private int nid;
    private String name;
    private double salary;
    public MyEmployee(int nid, String name, double salary) {
        super();
        this.nid = nid;
        this.name = name;
        this.salary = salary;
    }
    public int getNid() {
        return nid;
    }
    public void setNid(int nid) {
        this.nid = nid;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public double getSalary() {
        return salary;
    }
    public void setSalary(double salary) {
        this.salary = salary;
    }
    
    @Override
    public int compareTo(MyEmployee o) {
        
        if (this.salary < o.salary) {
            return -1;
        }else if (this.salary > o.salary) {
            return 1;
        }else {
             if (this.nid < o.nid) {
                    return -1;
                }else if (this.nid > o.nid) {
                    return 1;
                }else {
                    return 0;
                }
        }
    }
    
    
}