2008-02-29
根据集合中对象属性排序的方法
package Collection;
import java.util.*;
public class Sort {
private static ArrayList list = new ArrayList();
private static UserBean[] user = new UserBean[4];
public static void main(String[] args) {
Sort sort = new Sort();
user[0] = new UserBean("004",34);
user[1] = new UserBean("003",56);
user[2] = new UserBean("010",1);
user[3] = new UserBean("002",22);
for (int i = 0; i < 4; i++) {
list.add(user[i]);
}
//arg1排序列表，arg2列表顺序比较器为null时使用自然排序
Collections.sort(list,new ReverseSort());
//arg1排序列表，arg2改变列表的随机源
//Collections.shuffle(list,new Random());
for (Iterator iterator = list.listIterator();iterator.hasNext()) {
System.out.println(((UserBean)iterator.next()).name);
}
}
}
class UserBean implements Comparable{
public String name;
public int age;
public UserBean(String name,int age) {
this.name = name;
this.age = age;
}
//类对象属性进行比较时，继承一个自然排序接口，重写一个自然比较方法
public int compareTo(Object obj) {
UserBean user = (UserBean)obj;
return this.name.compareTo(user.name);
}
}
//自定义反向排序比较器
class ReverseSort implements Comparator{
public int compare(Object obj1,Object obj2) {
UserBean user1 = (UserBean)obj1;
UserBean user2 = (UserBean)obj2;
return -user1.name.compareTo(user2.name);
}
}
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