Java中list<Object[]>、list<Student>、list<Map<String,String>>排序

public static void main(String[] args) {

// TODO Auto-generated method stub

Object[] o1=new Object[4];

o1[0]="5";

o1[1]="o1";

o1[2]="o11";

o1[3]="o111";

Object[] o2=new Object[4];

o2[0]="3";

o2[1]="o2";

o2[2]="o22";

o2[3]="o222";

List<Object[]> list=new ArrayList<>();

list.add(o1);

list.add(o2);

 

//很明显我们先添加的对象o1，所以先打印o1，

for(inti=0;i<list.size();i++){

for(intj=0;j<4;j++){

System.out.print(list.get(i)[j]+"  ");

}

}

 

System.out.println("\n排序后-------");

sortList(list);

 

//排序后：

for(inti=0;i<list.size();i++){

for(intj=0;j<4;j++){

System.out.print(list.get(i)[j]+"  ");

}

}

public staticvoid sortList(List<Object[]>ls){

Collections.sort(ls,new Comparator<Object[]>() {

@Override

public int compare(Object[] o1, Object[] o2) {

if(Integer.valueOf(o1[0].toString())>Integer.valueOf(o2[0].toString()))

{

return 1;

}

 

return -1;

}

});

}

package com.model;

 

public class Student {

public Stringname;

publicintage;

public Student(Stringname,intage){

this.name=name;

this.age=age;

}

public void setName(String name){

this.name=name;

}

public String getName(){

returnname;

}

 

public void setAge(int age){

this.age=age;

}

public int getAge(){

returnage;

}

}

Student stu1=new Student("张三",23);

Student stu2=new Student("李四",25);

List<Student> listStudent=new ArrayList<>();

listStudent.add(stu1);

listStudent.add(stu2);

 

System.out.println();

for(int i=0;i<listStudent.size();i++){

System.out.print(listStudent.get(i).getName()+"---"+listStudent.get(i).getAge());

 

}

System.out.println("\n排序后");

sortListStudent(listStudent);

for(int i=0;i<listStudent.size();i++){

System.out.print(listStudent.get(i).getName()+"---"+listStudent.get(i).getAge());

 

}

public staticvoid sortListStudent(List<Student>ls){

Collections.sort(ls,new Comparator<Student>() {

 

@Override

public int compare(Student o1, Student o2) {

String s1=o1.getName();

String s2=o2.getName();

if(s1.compareTo(s2)>0){

return -1;

}

return 1;

}

 

});

 

}

 
 
}

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class MapListSort {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        List<Map<String,String>> listMap=new ArrayList<>();
        Map<String, String> map1=new HashMap<String, String>();
        map1.put("map001", "001");
        map1.put("map003", "map003");
        map1.put("map002", "map002");
        Map<String, String> map2=new HashMap<String, String>();
        map2.put("map001", "101");
        map2.put("map003", "map303");
        map2.put("map002", "map202");
        //先添加的map2，但是map2中map001的值大于map1中的map001的值。
        listMap.add(map2);
        listMap.add(map1);
        
        for(int i=0;i<listMap.size();i++){
                System.out.print(listMap.get(i).get("map001")+","+listMap.get(i).get("map002")+","+listMap.get(i).get("map003")+"\n");
                
        }
        
        mapSorts(listMap);
        
        System.out.println("\n排序后：");
        for(int i=0;i<listMap.size();i++){
            System.out.print(listMap.get(i).get("map001")+","+listMap.get(i).get("map002")+","+listMap.get(i).get("map003")+"\n");
    }


    }
    
    public static void mapSorts(List<Map<String,String>> map){
        Collections.sort(map,new Comparator<Map<String,String>>() {

            @Override
            public int compare(Map<String, String> o1, Map<String, String> o2) {
                // TODO Auto-generated method stub
                if(o1.get("map001").compareTo(o2.get("map001"))>0){
                    return 1;
                    
                }
                return -1;
            }
        });

    }

}