实现Compareble接口,自定义排序. java

【实现Compareble接口,自定义排序.】-实体类实现Comparable接口

//用户对象 public class UserPOJO implements Comparable {private String name; private int age; @Override public int compareTo(UserPOJO o) { return o.getAge()-this.age; }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; }}

使用Collections的sort()方法排序

public class Test { public static void main(String[] args) {UserPOJO u1 = new UserPOJO(); UserPOJO u2 = new UserPOJO(); UserPOJO u3 = new UserPOJO(); u1.setAge(2); u1.setName("小二"); u2.setAge(3); u2.setName("小三"); u3.setAge(1); u3.setName("小一"); List list = new ArrayList<>(); list.add(u1); list.add(u2); list.add(u3); Collections.sort(list); for (UserPOJO u : list) { System.out.println(u.getAge()); //System.out.println(u.getName()); } } }