对Map中数据,按value值排序方法

Map<String,Integer>类型Integer

//声明
Map<String,Integer> hashMap = new HashMap<String,Integer>();
//向Map中添加数据
//TODO...
//转换
ArrayList<Entry<String, Integer>> arrayList = new ArrayList<Entry<String, Integer>>(hashMap.entrySet());
//排序
Collections.sort(arrayList, new Comparator<Map.Entry<String, Integer>>() {
    public int compare(Map.Entry<String, Integer> map1, Map.Entry<String, Integer> map2) {
        return (map2.getValue() - map1.getValue());
    }
});

//输出
for (Entry<String, Integer> entry : arrayList) {
    System.out.println(entry.getKey() + "\t" + entry.getValue());
}

Map<String,Float>类型Float

//声明
Map<String,Float> hashMap = new HashMap<String,Float>();
//向Map中添加数据
//.....
//转换
ArrayList<Entry<String, Float>> arrayList = new ArrayList<Map.Entry<String,Float>>(hashMap.entrySet());
//排序
Collections.sort(arrayList, new Comparator<Map.Entry<String, Float>>(){
    public int compare(Map.Entry<String, Float> map1, Map.Entry<String,Float> map2) {
	    return ((map2.getValue() - map1.getValue() == 0) ? 0: (map2.getValue() - map1.getValue() > 0) ? 1: -1);
    }
});
//输出
for (Entry<String, Float> entry : arrayList) {
    System.out.println(entry.getKey() + "\t" + entry.getValue());
}


Map<String,Double>类型Double

//声明
Map<String,Double> hashMap = new HashMap<String,Double>();
//向Map中添加数据
//.....
//转换
ArrayList<Entry<String, Double>> arrayList = new ArrayList<Map.Entry<String,Double>>(hashMap.entrySet());
//排序
Collections.sort(arrayList, new Comparator<Map.Entry<String, Double>>(){
    public int compare(Map.Entry<String, Double> map1, Map.Entry<String,Double> map2) {
        return ((map2.getValue() - map1.getValue() == 0) ? 0 : (map2.getValue() - map1.getValue() > 0) ? 1 : -1);
    }
});
//输出
for (Entry<String, Double> entry : arrayList) {
    System.out.println(entry.getKey() + "\t" + entry.getValue());
}

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