Java实现词频统计(Wordcount)-Map或Hashtable的value排序

package com.qian;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.Hashtable;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
/*
* author:合肥工业大学 管院学院 钱洋
* email：1563178220@qq.com
*/
public class WordCount {
public static void main(String args []) throws IOException {
Hashtable<String, Integer>  wordCount = new Hashtable<String, Integer>();
BufferedReader reader = new BufferedReader( new InputStreamReader( new FileInputStream( new File("E:\\钱洋个人\\预测数据\\文本合并\\user_content_combine")),"utf-8"));
BufferedWriter Writer = new BufferedWriter( new OutputStreamWriter( new FileOutputStream( new File("E:\\钱洋个人\\预测数据\\wordcount\\user_content_count.txt")),"utf-8"));
String s=null;
int c=0;
while ((s=reader.readLine())!=null) {
String arry[] =s.split(" ");
for (int i = 0; i < arry.length; i++) {
if (!wordCount.containsKey(arry[i])) {
wordCount.put(arry[i], Integer.valueOf(1));
} else {
wordCount.put(arry[i], Integer.valueOf(wordCount.get(arry[i]).intValue() + 1));
}
}
}
for (java.util.Map.Entry<String, Integer> j : wordCount.entrySet()) {
String key = j.getKey();
int value = j.getValue();
Writer.append(key+" "+value+"\r\n");
}
//if the number of the word is 1,output the word and the number

//将map.entrySet()转换成list
List<Map.Entry<String, Integer>> list = new ArrayList<Map.Entry<String, Integer>>(wordCount.entrySet());
Collections.sort(list, new Comparator<Map.Entry<String, Integer>>() {
//降序排序
public int compare(Entry<String, Integer> o1, Entry<String, Integer> o2) {
//return o1.getValue().compareTo(o2.getValue());
return o2.getValue().compareTo(o1.getValue());
}
});

for (Map.Entry<String, Integer> mapping : list) {
System.out.println(mapping.getKey() + ":" + mapping.getValue());
}

}

}