Hadoop之HDFS的Java Interface(三)

package com.hdfs;import java.io.BufferedInputStream;import java.io.FileInputStream;import java.io.IOException;import java.io.InputStream;import java.net.URI;import java.net.URISyntaxException;import java.net.URL;import org.apache.hadoop.conf.Configuration;import org.apache.hadoop.fs.FSDataOutputStream;import org.apache.hadoop.fs.FileStatus;import org.apache.hadoop.fs.FileSystem;import org.apache.hadoop.fs.FsUrlStreamHandlerFactory;import org.apache.hadoop.fs.Path;import org.apache.hadoop.io.IOUtils;public class FileUtilsDemo {public static void main(String[] args) throws Exception {String hdfsPath = "hdfs://192.168.6.108:9000";String fileName = "hdfs://192.168.6.108:9000/usr/input/test.txt";String filePath = "hdfs://192.168.6.108:9000/usr/input/test";String fileList = "hdfs://192.168.6.108:9000/usr/input";String reNameFileName = "hdfs://192.168.6.108:9000/usr/input/a.txt";String inputFileName = "input/test.txt";// 读取文件内容// readFile(fileName);// 获取文件列表// getFileList(fileList);// 创建文件夹// createFile(hdfsPath,filePath);// 删除文件夹以及文件夹中的文件// deleteFile(hdfsPath, filePath, true);// 重命名文件//reNameFileName(hdfsPath, reNameFileName);// 追加内容到指定文件中appendFileToHdfs(hdfsPath, fileName, inputFileName);}/** * 追加内容到指定文件中 *  * @param hdfsPath * @param fileName * @throws inputFileName  * @throws Exception  */public static void appendFileToHdfs(String hdfsPath, String hdfsFileName, String inputFileName) throws Exception {Configuration conf = new Configuration();conf.setBoolean("dfs.support.append", true);// 如果在linux环境修改了这个参数没有重启hdfs则在这里还是重新设置一次，在linux中进行修改时如果在linux环境运行则无需重启hdfsconf.set("dfs.client.block.write.replace-datanode-on-failure.policy", "NEVER");  FileSystem fileSystem = FileSystem.get(new URI(hdfsPath), conf);InputStream in = new BufferedInputStream(new FileInputStream(inputFileName));FSDataOutputStream out = fileSystem.append(new Path(hdfsFileName));IOUtils.copyBytes(in, out, 4096, true);System.out.println("已添加完");}/** * 对文件进行重命名 *  * @param hdfsPath * @param reNameFileName * @throws Exception */public static void reNameFileName(String hdfsPath, String reNameFileName) throws Exception {FileSystem fileSystem = FileSystem.get(new URI(hdfsPath), new Configuration());boolean flag = fileSystem.rename(new Path(reNameFileName), new Path(reNameFileName + "tmp"));System.out.println(flag);}/** * 读取文件的内容 *  * @param filePath * @throws IOException */public static void readFile(String filePath) throws IOException {URL.setURLStreamHandlerFactory(new FsUrlStreamHandlerFactory());URL url = new URL(filePath);InputStream in = url.openStream();IOUtils.copyBytes(in, System.out, 1024, true);}/** * 获取文件列表 *  * @param filePath * @throws URISyntaxException * @throws IOException */@SuppressWarnings("deprecation")public static void getFileList(String filePath) throws Exception {FileSystem fileSystem = FileSystem.get(new URI(filePath), new Configuration());FileStatus[] listStatus = fileSystem.listStatus(new Path(filePath));for (FileStatus fileStatus : listStatus) {if (fileStatus.isDir()) {System.out.println(fileStatus.getPath().toString());getFileList(fileStatus.getPath().toString());} else {System.out.println(fileStatus.isDir() ? "文件夹": "文件" + " " + fileStatus.getOwner() + " " + fileStatus.getReplication() + " "+ fileStatus.getPath());}}}/** * 创建文件夹 *  * @param filePath * @throws Exception */public static void createFile(String hdfsPath, String filePath) throws Exception {Configuration conf = new Configuration();URI uri = new URI(hdfsPath);FileSystem fileSystem = FileSystem.get(uri, conf);boolean flag = fileSystem.mkdirs(new Path(filePath));System.out.println(flag);}/** * 删除文件 *  * @param hdfsPath * @param filePath * @param isDelete 是否递归删除文件夹中的文件 * @throws Exception */public static void deleteFile(String hdfsPath, String filePath, boolean isDelete) throws Exception {Configuration conf = new Configuration();URI uri = new URI(hdfsPath);FileSystem fileSystem = FileSystem.get(uri, conf);boolean flag = fileSystem.delete(new Path(filePath), true);System.out.println(flag);}}