Java List集合排序实现方法解析

这篇文章主要介绍了Java List集合排序实现方法解析,文中通过示例代码介绍的非常详细，对大家的学习或者工作具有一定的参考学习价值,需要的朋友可以参考下

1.使用 Collections 工具类中的 sort() 方法

参数不同：

void sort(List list) 在自定义类User里面实现Comparable<User>接口，并重写抽象方法compareTo(Student o);

void sort(List list, Comparator c) 第二个参数为了省事，可以直接使用匿名内部类

public class User implements Comparable<User>{

private int score;

private int age;

public User(int score, int age){
   super();
   this.score = score;
   this.age = age;
 }

public int getScore() {
   return score;
 }

public void setScore(int score) {
   this.score = score;
 }

public int getAge() {
   return age;
 }

public void setAge(int age) {
   this.age = age;
 }

@Override
 public int compareTo(User o) {
   int i = this.getAge() - o.getAge();//先按照年龄排序
   if(i == 0){
     return this.score - o.getScore();//如果年龄相等了再用分数进行排序
   }
   return i;
 }

}

public static void main(String[] args) {
   List<User> users = new ArrayList<User>();
   users.add(new User(78, 26));
   users.add(new User(67, 23));
   users.add(new User(34, 56));
   users.add(new User(55, 23));
   Collections.sort(users);
   for(User user : users){
     System.out.println(user.getScore() + "," + user.getAge());
   }
}

public class Students {

private int age;
 private int score;

public Students(int age, int score){
   super();
   this.age = age;
   this.score = score;
 }

public int getAge() {
   return age;
 }
 public void setAge(int age) {
   this.age = age;
 }
 public int getScore() {
   return score;
 }
 public void setScore(int score) {
   this.score = score;
 }
}
public static void main(String[] args) {
   List<Students> students = new ArrayList<Students>();
   students.add(new Students(23, 100));
   students.add(new Students(27, 98));
   students.add(new Students(29, 99));
   students.add(new Students(29, 98));
   students.add(new Students(22, 89));
   Collections.sort(students, new Comparator<Students>() {

@Override
     public int compare(Students o1, Students o2) {
       int i = o1.getScore() - o2.getScore();
       if(i == 0){
         return o1.getAge() - o2.getAge();
       }
       return i;
     }
   });
   for(Students stu : students){
     System.out.println("score:" + stu.getScore() + ":age" + stu.getAge());
   }
}

2.直接使用list.sort()方法，传入实现Comparator接口的实现类的实例，为了省事直接传入匿名内部类

public class Students {

private int age;
 private int score;

public Students(int age, int score){
   this.age = age;
   this.score = score;
 }

public int getAge() {
   return age;
 }
 public void setAge(int age) {
   this.age = age;
 }
 public int getScore() {
   return score;
 }
 public void setScore(int score) {
   this.score = score;
 }
}
public static void main(String[] args) {
List<Students> students = new ArrayList<Students>();
students.add(new Students(23, 100));
students.add(new Students(27, 98));
students.add(new Students(29, 99));
students.add(new Students(29, 98));
students.add(new Students(22, 89));

students.sort(new Comparator<Students>() {
@Override
public int compare(Students o1, Students o2) {
int i = o1.getScore() - o2.getScore();
if (i == 0) {
return o1.getAge() - o2.getAge();
}
return i;
}
});

for (Students stu : students) {
System.out.println("score:" + stu.getScore() + ":age" + stu.getAge());
}
}

来源：https://www.cnblogs.com/roadlandscape/p/12093907.html