1,寫一個對象,實現Comparable
package com.baizhi.test1.pojo;
public class User implements Comparable {
private int id;
private String name;
private int age;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public User(String name, int age) {
this.name = name;
this.age = age;
}
@Override
public int compareTo(User o) {
if (o.age<this.age){//這裏是大於的話最後出來的結果是倒敘,否則是從小到大
return 1;
}else if (o.age<this.age){
return 0;
} else {
return -1;
}
}
@Override
public String toString() {
return "User{" +
"name='" + name + '\'' +
", age=" + age +
'}';
}
}
2,寫一個測試方法
package com.baizhi.test1.test;
import com.baizhi.test1.pojo.User;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
public class Test {
public static void main(String[] args) {
List<User> list = new ArrayList<User>();
list.add(new User("zhou", 12));
list.add(new User("meng", 11));
list.add(new User("jun", 13));
Collections.sort(list);//通過Collections類的sort()方法排序
//遍歷
for(User user : list){
System.out.println(user);
}
}
}