java集合排序

实现Comparable接口

@Getter
@Setter
public class User implements Comparable<User> {
    private String age;
     private String name;
    @Override
    public int compareTo(User o) {
        return this.getAge() > o.getAge();
    }
}

实现Comparator接口

public class DemoComparator implements Comparator<User>{
    @Override
    public int compare(User o1, User o2) {
            return o1.getName().compareTo(o2.getName());
    }
}

倒序排序

Collections.reverse(demoList);