Map按照String作为key来排序

package com.huawei.test;

import java.util.Comparator;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import java.util.TreeMap;

public class Sorter {
    public static Map sort(Map map,final boolean flag) {
        Map<Object, Object> mapVK = new TreeMap<Object, Object>(
            new Comparator<Object>() {
                public int compare(Object obj1, Object obj2) {
                    String v1 = (String)obj1;
                    String v2 = (String)obj2;
                    int s = v2.compareTo(v1);
                    if(flag)
                    {
                        return s;    
                    }else
                    {
                        return -s;
                    }
                    
                }
            }
        );
        Set col = map.keySet();
        Iterator iter = col.iterator();
        while (iter.hasNext()) {
            String key = (String) iter.next();
            Integer value = (Integer) map.get(key);
            mapVK.put(key, value);
        }
        return mapVK;
    }

}




//Test 

//其中true,代表按String 降序，false 为按String 升序
package com.huawei.test;

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;

public class SortHashMap {
  
    public static void main(String[] args) {
        Map<String, Integer> maps = new HashMap<String, Integer>();
        maps.put("boy", 8);
        maps.put("cat", 7);
        maps.put("dog", 1);
        maps.put("apple", 5);
        maps.put("abcd", 5);
        maps.put("bcasd", 3);
        maps.put("heasdf", 2);
        //排序前的输出
        Set set = maps.entrySet();
        Iterator i = set.iterator();
        while(i.hasNext()){
            Map.Entry<String, Integer> entry1=(Map.Entry<String, Integer>)i.next();
            System.out.println(entry1.getKey() + "-------->" + entry1.getValue());
        }
        System.out.println("----------------");
         //排序后的输出
        Map<String, Integer> sortMaps = Sorter.sort(maps,false);
        Set sortSet = sortMaps.entrySet();
        Iterator ii = sortSet.iterator();
        while(ii.hasNext()){
            Map.Entry<String, Integer> entry1=(Map.Entry<String, Integer>)ii.next();
            System.out.println(entry1.getKey() + ":" + entry1.getValue());
        }
        
    }
}