LinkedList 实现排序

import java.util.Collections;
import java.util.Comparator;
import java.util.LinkedList;

class Person{
    private float height;
    private String name;
    
    Person(float height)
    {
        this.height=height;
    }

    public float getHeight() {
        return height;
    }

    public void setHeight(float height) {
        this.height = height;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }
}

class PersonHeight implements Comparator<Person>{
     
    @Override
    public int compare(Person e1, Person e2) {
        if(e1.getHeight() < e2.getHeight()){
            return 1;
        } else {
            return -1;
        }
    }
}


public class Question3 {

    public static void main(String[] args) {
        Person p1=new Person(23.4f);
        p1.setName("Stud1");
        Person p2=new Person(2.34f);
        p2.setName("Stud2");
        Person p3=new Person(34.32f);
        p3.setName("Stud3");
        Person p4=new Person(56.45f);
        p4.setName("Stud4");
        Person p5=new Person(21.4f);
        p5.setName("Stud5");
             
        LinkedList<Person> al=new LinkedList<Person>();
        al.add(p1);
        al.add(p2);
        al.add(p3);
        al.add(p4);
        al.add(p5);
        
        
        
        Collections.sort(al,new PersonHeight());
        for(Person p:al)
            System.out.println(p.getName()+" "+p.getHeight());

    }

}

  Collections.sort(al,new PersonHeight());



结果：
Stud4 56.45
Stud3 34.32
Stud1 23.4
Atud5 21.4
Stud2 2.34

package com.cn.aug26;


import java.util.Collections;
import java.util.LinkedList;
7 
class Person1 implements Comparable <Person1>{
    private Float height;
    private String name;
    
    Person1(float height)
    {
        this.height=height;
    }

    public Float getHeight() {
        return height;
    }

    public void setHeight(float height) {
        this.height = height;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    @Override
    public int compareTo(Person1 p) {
        if(this.getHeight()<p.getHeight()){
            return 1;
            
        }else if(this.getHeight()>p.getHeight()){
            return -1;
        }else{
            return 0;    
        }
        
    }
}


public class Question3_1 {

    public static void main(String[] args) {
        Person1 p1=new Person1(23.4f);
        p1.setName("Stud1");
        Person1 p2=new Person1(2.34f);
        p2.setName("Stud2");
        Person1 p3=new Person1(34.32f);
        p3.setName("Stud3");
        Person1 p4=new Person1(56.45f);
        p4.setName("Stud4");
        Person1 p5=new Person1(21.4f);
        p5.setName("Stud5");
        
        LinkedList<Person1> al=new LinkedList<Person1>();
       
        al.add(p1);
        al.add(p2);
        al.add(p3);
        al.add(p4);
        al.add(p5);
        
        Collections.sort(al);//降序
       
        for(Person1 p:al)
            System.out.println(p.getName()+" "+p.getHeight());

    }

}

结果：
Stud4 56.45
Stud3 34.32
Stud1 23.4
Stud5 21.4
Stud2 2.34

 Collections.sort(al,Collections.reverseOrder());//升序

结果：
Stud2 2.34
Stud5 21.4
Stud1 23.4
Stud3 34.32
Stud4 56.45


若身高相同，比较姓名，修改compareTo 方法：

@Override
    public int compareTo(Person1 p) {
        if(this.getHeight()<p.getHeight()){
            return 1;
            
        }else if(this.getHeight()>p.getHeight()){
            return -1;
        }else{
            return this.name.compareTo(p.name);    
        }
        
    }