1. 读取txt文件：

使用ClassPathResource的原因在https://blog.csdn.net/nnnora/article/details/80734326中阐述过，因为是springboot内置web容器所以不能使用FileInputStream的方式获取文件流。

            //读取txt文件ClassPathResource classPathResource = new ClassPathResource("test.txt");InputStreamReader inputStreamReader = new InputStreamReader(classPathResource.getInputStream());BufferedReader bufferedReader = new BufferedReader(inputStreamReader);StringBuffer buffer = new StringBuffer();String line = null;while( (line = bufferedReader.readLine()) != null ){buffer.append(line);}bufferedReader.close();String buffer = buffer.toString();

2. 写入txt文件：

            //写入txtBufferedWriter bufw = new BufferedWriter(new FileWriter("D:\\test\\result.txt"));for(Map.Entry<String, Integer> me : list){bufw.write(me+"");bufw.newLine();}bufw.close();

3. 读取word文档

1. 首先需要引入以下jar包：

分别是操作doc和docx格式需要的jar包，关于引入jar包的语句格式可以去http://jareye.com/查找，可以导出maven或者gradle等工具下的compile语句。

2. 读取word文档：

        try {//读取word文件String path = "Shocking level of sexual harassment at music festivals.docx";String buffer = "";if (path.endsWith(".doc")) {ClassPathResource classPathResource = new ClassPathResource(path);WordExtractor wordExtractor = new WordExtractor(classPathResource.getInputStream());buffer = wordExtractor.getText();} else if (path.endsWith("docx")) {ClassPathResource classPathResource = new ClassPathResource(path);XWPFDocument xdoc = new XWPFDocument(classPathResource.getInputStream());POIXMLTextExtractor extractor = new XWPFWordExtractor(xdoc);buffer = extractor.getText();} else {System.out.println("此文件不是word文件！");}}catch (Exception e){logger.error("@@ReadFileError", e);}

4. 写入excel文档