java：util：MapUtil

import java.util.*;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;

public class MapUtil {




    /**
     * 使用 Map按value進行排序(value爲String類型)
     * @param oriMap
     * @return
     */
    public static Map<String, String> sortMapByValueStr(Map<String, String> oriMap) {
        if (oriMap == null || oriMap.isEmpty()) {
            return null;
        }
        Map<String, String> sortedMap = new LinkedHashMap<String, String>();
        List<Map.Entry<String, String>> entryList = new ArrayList<Map.Entry<String, String>>(
                oriMap.entrySet());
        Collections.sort(entryList, new MapValueComparator());

        Iterator<Map.Entry<String, String>> iter = entryList.iterator();
        Map.Entry<String, String> tmpEntry = null;
        while (iter.hasNext()) {
            tmpEntry = iter.next();
            sortedMap.put(tmpEntry.getKey(), tmpEntry.getValue());
        }
        return sortedMap;
    }


    /**
     * 使用 Map按value進行排序 升序(value爲Double類型)
     * @param map
     * @return
     */
    public static Map<String, Double> sortMapByValueDob(Map<String, Double> map) {
        List<Map.Entry<String, Double>> wordMap = new ArrayList<Map.Entry<String, Double>>(map.entrySet());
//		System.out.println(wordMap);
        Collections.sort(wordMap, new Comparator<Map.Entry<String, Double>>() {// 根據value排序
            public int compare(Map.Entry<String, Double> o1, Map.Entry<String, Double> o2) {
                double result = o1.getValue() - o2.getValue();//升序降序交換位置即可
                if (result > 0)
                    return 1;
                else if (result == 0)
                    return 0;
                else
                    return -1;
            }
        });
        System.out.println("------------map按照value升序排序--------------------");
        Map<String, Double> ma = new LinkedHashMap<String, Double>();
        for (Map.Entry<String, Double> entry : wordMap) {
//	        System.out.println(entry.getKey() + "->" + entry.getValue());
            ma.put(entry.getKey(),entry.getValue());
        }

        return ma;
    }

    /**
     * 使用 Map按value進行排序 降序(value爲Double類型)
     * @param map
     * @return
     */
    public static Map<String, Double> sortMapByValueDobDown(Map<String, Double> map) {
        List<Map.Entry<String, Double>> wordMap = new ArrayList<Map.Entry<String, Double>>(map.entrySet());
//		System.out.println(wordMap);
        Collections.sort(wordMap, new Comparator<Map.Entry<String, Double>>() {// 根據value排序
            public int compare(Map.Entry<String, Double> o1, Map.Entry<String, Double> o2) {
                double result = o2.getValue() - o1.getValue();//升序降序交換位置即可
                if (result > 0)
                    return 1;
                else if (result == 0)
                    return 0;
                else
                    return -1;
            }
        });
        System.out.println("------------map按照value降序排序--------------------");
        Map<String, Double> ma = new LinkedHashMap<String, Double>();
        for (Map.Entry<String, Double> entry : wordMap) {
//	        System.out.println(entry.getKey() + "->" + entry.getValue());
            ma.put(entry.getKey(),entry.getValue());
        }

        return ma;
    }

}