1.使用poi生成excel，上传hdfs
2.当有需要的时候，去下载该文件
3.下载文件是通过rest接口
4.接口中通过hdfs api读取hdfs上的excel文件内容，并转成字符串，响应到客户端

图1 通过hdfs的get命令拉去的文件，显示正常

图2 通过hdfs的java api下载的文件内容，显示乱码
最原始的代码：

public static String readFile(Configuration conf, String filePath) throws IOException, URISyntaxException { String fileContent = null; FileSystem fs = getFileSystem(conf); Path path = new Path(filePath); InputStream inputStream = null; ByteArrayOutputStream outputStream = null; try { inputStream = fs.open(path); outputStream = new ByteArrayOutputStream(inputStream.available()); IOUtils.copyBytes(inputStream, outputStream, conf); byte[] lens = outputStream.toByteArray(); //解决中文乱码 fileContent = new String(lens, "UTF-8"); } finally { IOUtils.closeStream(inputStream); IOUtils.closeStream(outputStream); fs.close(); } return fileContent; }

修改后的代码：

/** * 读取文件内容 * * @param conf * @param filePath * @return * @throws IOException */ public static String readFile(Configuration conf, String filePath) throws IOException, URISyntaxException { String fileContent = null; FileSystem fs = getFileSystem(conf); Path path = new Path(filePath); FSDataInputStream in = null; ByteArrayOutputStream outputStream = null; try { in = fs.open(path); outputStream = new ByteArrayOutputStream(); //IOUtils.copyBytes(in, outputStream, conf); //这个也是乱码 byte[] b = new byte[1024]; int numBytes = 0; while ((numBytes = in.read(b)) > 0) { outputStream.write(b, 0, numBytes); } fileContent = new String(outputStream.toByteArray(), "UTF8"); } finally { IOUtils.closeStream(in); IOUtils.closeStream(outputStream); fs.close(); } return fileContent;

网上的方法基本都用过了，ByteArrayOutputStream换成FsDataOutputStream也尝试过了，也是乱码。

public static String readFile(Configuration conf, String filePath) throws IOException, URISyntaxException { String fileContent = null; FileSystem fs = getFileSystem(conf); Path path = new Path(filePath); FSDataInputStream fin = null; InputStreamReader bin = null; int line; try { StringBuffer buffer = new StringBuffer(); fin = fs.open(path); bin = new InputStreamReader(fin, "UTF-8"); while ((line = bin.read()) > 0) { buffer.append(line); } fileContent = new String(buffer); } finally { IOUtils.closeStream(fin); IOUtils.closeStream(bin); fs.close(); } return fileContent; }

使用System.out也是乱码：

public static String readFile(Configuration conf, String filePath) throws IOException, URISyntaxException { String fileContent = null; FileSystem fs = getFileSystem(conf); Path path = new Path(filePath); FSDataInputStream in = null; int line; try { in = fs.open(path); IOUtils.copyBytes(in, System.out, 4096, false); fileContent = new String(""); } finally { IOUtils.closeStream(in); fs.close(); } return fileContent; }

我对IO流不熟悉，求大神们帮忙看看！