List<T> 排序问题分享

1. 先写好自己的pojo类 如User类

2. 写好自己的Comparator类，如下

public class ComparatorEmp implements Comparator<User> {

public int compare(User arg0, User arg1) {

int flag = arg0.getWorkNo().compareTo(arg1.getWorkNo());

return flag;

}

public static void main(String[] args) {

List<User> userlist = new ArrayList<User>();

Usere = new User();

e.setWorkNo("001");

Usere1 = new User();

e1.setWorkNo("004");

Usere2 = new User();

e2.setWorkNo("002");

Usere3 = new User();

e3.setWorkNo("003");

userlist.add(e);

userlist.add(e1);

userlist.add(e2);

userlist.add(e3);

ComparatorEmp comparator = new ComparatorEmp();

Collections.sort(userlist, comparator);

for (int i = 0; i < userlist.size(); i++) {

Useruser = (User) userlist.get(i);

System.out.println(user .getWorkNo());

}

}

}

3. 打印001 002 003 004