Java案例：统计单词个数

1、文本文件test.txt



2、创建Java项目JavaWordCount实现词频统计



package net.hw.wc;

import java.io.BufferedReader;
import java.io.FileReader;
import java.util.HashMap;
import java.util.Map;

/**
* Created by howard on 2018/2/6.
*/
public class WordCount {
public static void main(String[] args) throws Exception {
BufferedReader br = new BufferedReader(new FileReader("test.txt"));
Map<String, Integer> map = new HashMap<>();
String nextLine = "";
while ((nextLine = br.readLine()) != null) {
String[] data = nextLine.split(" ");
for (String word : data) {
map.put(word, map.containsKey(word) ? map.get(word) + 1 : 1);
}
}

for (String key : map.keySet()) {
System.out.println(key + ": " + map.get(key));
}
}
}运行结果如下：