java list排序的2种方法

第一种方法，就是list中对象实现Comparable接口，代码如下：
public class Person implements Comparable<Person> {
    private String name;
    private Integer order;

    /**
     * @return the name
     */
    public String getName() {
        return name;
    }

    /**
     * @param name
     *            the name to set
     */
    public void setName(String name) {
        this.name = name;
    }

    /**
     * @return the order
     */
    public Integer getOrder() {
        return order;
    }

    /**
     * @param order
     *            the order to set
     */
    public void setOrder(Integer order) {
        this.order = order;
    }

    @Override
    public int compareTo(Person arg0) {
        return this.getOrder().compareTo(arg0.getOrder());
    }

}

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第二种方法，就是在重载Collections.sort方法，代码如下：

public class Person {
    private String name;
    private Integer order;

    /**
     * @return the name
     */
    public String getName() {
        return name;
    }

    /**
     * @param name
     *            the name to set
     */
    public void setName(String name) {
        this.name = name;
    }

    /**
     * @return the order
     */
    public Integer getOrder() {
        return order;
    }

    /**
     * @param order
     *            the order to set
     */
    public void setOrder(Integer order) {
        this.order = order;
    }

}

public static void main(String[] args) {
        List<Person> listA = new ArrayList<Person>();
        Person p1 = new Person();
        Person p2 = new Person();
        Person p3 = new Person();

        p1.setName("name1");
        p1.setOrder(1);
        p2.setName("name2");
        p2.setOrder(2);
        p3.setName("name3");
        p3.setOrder(3);

        listA.add(p2);
        listA.add(p1);
        listA.add(p3);
        
        Collections.sort(listA, new Comparator<Person>() {
            public int compare(Person arg0, Person arg1) {
                return arg0.getOrder().compareTo(arg1.getOrder());
            }
        });
        
        for (Person p : listA) {
            System.out.println(p.getName());
        }
    }

两次执行的结果都是：

name1

name2

name3

//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;
  } 
from:http://www.cnblogs.com/wentiertong/archive/2011/03/07/1973698.html