對 List<map>內對象進行排序

 

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.*;


public class Main {

    /**
     * @param args
     */
    public static void main(String[] args) {
        Map<String,String> map1 = new HashMap<String, String>();
        map1.put("operationTime", "2010-01-10 12:20:00");

        Map<String,String> map2 = new HashMap<String, String>();
        map2.put("operationTime", "2010-01-10 12:40:00");

        Map<String,String> map3 = new HashMap<String, String>();
        map3.put("operationTime", "2010-01-10 12:30:00");

        List<Map<String,String>> list = new ArrayList<Map<String,String>>();
        list.add(map1);
        list.add(map2);
        list.add(map3);

        System.out.println("排序前的list：");
        System.out.println(list);

        final SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        Collections.sort(list, new Comparator<Map<String,String>>(){

            public int compare(Map<String, String> o1, Map<String, String> o2)
            {
                //取出操作時間
                int ret = 0;
                try
                {
                    ret = df.parse(o1.get("operationTime")).compareTo(df.parse(o2.get("operationTime")));
                } catch (ParseException e)
                {
                    throw new RuntimeException(e);
                }
                return  ret;
            }

        });

        System.out.println("排序後的list：");
        System.out.println(list);
    }

}
轉載地址：http://www.iteye.com/problems/34693