注：

    转载于 http://www.cnblogs.com/xingyun/archive/2012/12/09/2809962.html

package com.holdobject;

import java.util.ArrayList;

import java.util.Collections;

import java.util.Comparator;

import java.util.HashMap;

import java.util.List;

import java.util.Map;

import java.util.Map.Entry;

public class HashMapSort {

    public static void main(String[] args) {

        Map<String, Integer> map = new HashMap<String, Integer>();

        map.put("d", 3);

        map.put("c", 1);

        map.put("b", 1);

        map.put("a", 2);

        List<Map.Entry<String, Integer>> infoIds = new ArrayList<Map.Entry<String, Integer>>(

                map.entrySet());

        System.out.println("Before Sort....");

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

            System.out.println(infoIds.get(i).toString());

        }

        System.out.println("\n\nAfter Sort(Key)....");

        Collections.sort(infoIds, new Comparator<Map.Entry<String, Integer>>() {

            public int compare(Entry<String, Integer> o1,

                    Entry<String, Integer> o2) {

                return o1.getKey().toString().compareTo(o2.getKey());

            }

        });

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

            System.out.println(infoIds.get(i).toString());

        }

        System.out.println("\n\nAfter Sort(Value)....");

        Collections.sort(infoIds, new Comparator<Map.Entry<String, Integer>>() {

            public int compare(Entry<String, Integer> o1,

                    Entry<String, Integer> o2) {

                return o1.getValue() - (o2.getValue());

            }

        });

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

            System.out.println(infoIds.get(i).toString());

        }

    }

}