一個集合，集合儲存著若干物件，物件有若干屬性，希望按照物件的某個屬性排序，排序完成，list的儲存順序也是按照這個屬性排完以後的順序。

http://lanyinbin.cn/blog/articles/127.html

public class User {

    private String username;
    private int age;
 
    public String getUsername() {
        return username;
    }
 
    public void setUsername(String username) {
        this.username = username;
    }
 
    public int getAge() {
        return age;
    }
 
    public void setAge(int age) {
        this.age = age;
    }
 
    public User() {
    }
}
 
public class ListSortTest {
    public static void main(String args[]){
        List<User> userlist=new ArrayList<User>();
        User user1=new User();
        User user2=new User();
        User user3=new User();
        User user4=new User();
        user1.setAge(10);
        userlist.add(user1);
        user2.setAge(34);
        userlist.add(user2);
        user3.setAge(19);
        userlist.add(user3);
        user4.setAge(6);
        userlist.add(user4);
        System.out.println("排序前");
        for(User user:userlist){
 
            System.out.print(user.getAge() + "-");
        }
        System.out.println("\n");
        System.out.println("排序後");
        for(User user:getSortList(userlist)){
            System.out.print(user.getAge() + "-");
        }
 
    }
 
    public static List<User> getSortList(List<User> list){
        Collections.sort(list, new Comparator<User>() {
            @Override
            public int compare(User o1, User o2) {
                if(o1.getAge()>o2.getAge()){
                    return 1;
                }
                if(o1.getAge()==o2.getAge()){
                    return 0;
                }
                return -1;
            }
        });
        return list;
    }
}
 

6-10-19-34-