查找任意一英文文档，统计其单词出现次数

import java.io.*; import java.util.*; class Demo { public static void main(String[] args) { File f = new File("F:\\tx.txt"); BufferedReader br = null; BufferedWriter bw = null; try { br = new BufferedReader(new FileReader(f)); bw = new BufferedWriter(new FileWriter("cha.txt")); String line = null; Map<String,Integer> map = new TreeMap<String,Integer>(); while ((line = br.readLine()) != null) { // 正则表达式(获取) String reg = "\\b[a-zA-Z]+\\b"; // 将正则表达式封装为对象 Pattern p = Pattern.compile(reg); // 将正则表达式对象和要作用的字符串匹配 Matcher m = p.matcher(line.toLowerCase());//全部变为小写 int temp =0; while (m.find()) { //System.out.println(m.group()); //将单词存入treemap，值为其出现次数 Integer value = map.get(m.group()); if (value != null) temp = value; temp++; map.put(m.group(), temp); temp = 0; } bw.write(map.toString()); } System.out.println(map); } catch (IOException e) { e.printStackTrace(); } finally { try { if (br != null) br.close(); if (bw != null) bw.close(); } catch (IOException e) { e.printStackTrace(); } } } }