//一个POJO例子

class User {  String name; String age;  public User(String name,String age){   this.name=name;  this.age=age; } public String getAge() {   return age; } public void setAge(String age) {   this.age = age; } public String getName() {   return name; } public void setName(String name) {   this.name = name; } }

//具体的比较类，实现Comparator接口import java.util.Comparator;import java.util.List;import java.util.ArrayList;import java.util.Collections;public class ComparatorUser implements Comparator{

 public int compare(Object arg0, Object arg1) {

  User user0=(User)arg0;  User user1=(User)arg1;   //首先比较年龄，如果年龄相同，则比较名字  int flag=user0.getAge().compareTo(user1.getAge());  if(flag==0){    return user0.getName().compareTo(user1.getName());  }else{    return flag;  }   } }

//测试类public class SortTest {

 

 public static void main(String[] args){   List userlist=new ArrayList();  userlist.add(new User("dd","4"));  userlist.add(new User("aa","1"));  userlist.add(new User("ee","5"));  userlist.add(new User("bb","2"));    userlist.add(new User("ff","5"));  userlist.add(new User("cc","3"));  userlist.add(new User("gg","6"));    ComparatorUser comparator=new ComparatorUser();  Collections.sort(userlist, comparator);     for (int i=0;i<userlist.size();i++){    User user_temp=(User)userlist.get(i);      System.out.println(user_temp.getAge()+","+user_temp.getName());   }   }} //首先年龄排序，如果年龄相同，则按名字排序结果:   1, aa   2, bb   3, cc   4, dd   5, ee                    //注意:同样是5岁的人，则比较名字(ee,ff)，然后排序   5, ff   6, gg