两种比较器Comparable 和 Comparator

//通过两种比较器排序
//比较器
//
//Comparable:自然排序使用
//  规则：
//   this属性  参数对象o属性 比较
//   this > o 正数
//   this < o 负数
//   this == o 0
//
//Comparator：外部比较器
//
//
//
//--------------------------------------
//Comparable 和 Comparator区别：
//1.位置。
//  Comparable  代码写在要比较的类中；
//  Comparator  代码写在要比较的类外；
//2.个数。
//  Comparable  就定义一种；
//  Comparator  可以定义多个比较方式。                   
import java.util.Arrays;
public class TestTel {
    public static void main(String[] args) {
        Mumber[] mum = new Mumber[3];
        Mumber m1 = new Mumber("001", "张三", 500);
        Mumber m2 = new Mumber("010", "李四", 1100);
        Mumber m3 = new Mumber("006", "王五", 200);
        mum[0] = m1;
        mum[1] = m2;
        mum[2] = m3;
        //第一种Comparable 外部比较器
        Arrays.sort(mum);
        for(Mumber s :mum) {
            System.out.println(s);
        }    
    }
}

class Mumber implements Comparable<Mumber>{
    private String no;
    private String name;
    private int num;
    public String getNo() {
        return no;
    }
    public void setNo(String no) {
        this.no = no;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public int getNum() {
        return num;
    }
    public void setNum(int num) {
        this.num = num;
    }
    public Mumber(String no, String name, int num) {
        super();
        this.no = no;
        this.name = name;
        this.num = num;
    }
    @Override
    public int compareTo(Mumber o) {
        // TODO Auto-generated method stub
        return o.num-this.num;
    }
    @Override
    public String toString() {
        return "Student [no=" + no + ", name=" + name + ", num=" + num+"]";
    }
    
}

package day13;

import java.util.Arrays;
import java.util.Comparator;

class Employee{
    private String name;
    private int age;
    public Employee(String name, int age) {
        super();
        this.name = name;
        this.age = age;
    }
    public String getName() {
        return name;
    }
    public int getAge() {
        return age;
    }
    @Override
    public String toString() {
        return "Employee [name=" + name + ", age=" + age + "]";
    }
    
}
public class TestSort2 {

    public static void main(String[] args) {
        Employee guojing = new Employee("yangkang", 22);
        Employee yangkang = new Employee("guojing", 20);
        Employee huangrong = new Employee("huangrong", 21);
        
        Employee [] emps = {guojing,yangkang,huangrong};
        Arrays.sort(emps, new Comparator<Employee>(){
            @Override
            public int compare(Employee o1, Employee o2) {

    /*            if(o1.getName().compareTo(o2.getName()) > 0) {
                    return 1;
                }else if(o1.getName().compareTo(o2.getName()) < 0) {
                    return -1;
                }else {
                    if(o1.getAge() > o2.getAge() ) {
                        return 1;
                    }else if(o1.getAge() < o2.getAge()) {
                        return -1;
                    }else {
                        return 0;
                    }
                }*/
              if(o1.getName().compareTo(o2.getName()) == 0) {
                    return o1.getAge() - o2.getAge();
               }
               return o1.getName().compareTo(o2.getName());
            }
            
        });
        for(Employee emp : emps) {
            System.out.println(emp);
        }
        
        
    }

}