HDFS --API 操作

package com.hdfs;
 import java.io.IOException;
 import java.net.URI;
 import java.util.ArrayList;
 import java.util.List;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FSDataInputStream;
 import org.apache.hadoop.fs.FSDataOutputStream;
 import org.apache.hadoop.fs.FileStatus;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
 
public class HdfsTest {
 private FileSystem fs = null;
 private List<String> hdfsPathsLists;
 private FileSystem local = null;
 @ Before
 public void init() throws Exception {
     fs = FileSystem.get(new URI("hdfs://localhost:9000"), new Configuration(), "root");
     local = FileSystem.getLocal(new Configuration());
 }
 @After
 public void close() throws Exception {
     fs.close();
     local.close();
 }
 @Test
 public void testMkdir() throws Exception {
     boolean flag = fs.mkdirs(new Path("/javaApi/mk/dir1/dir2"));
     System.err.println(flag ? "success" : "fail");
 }
 @Test
 public void getDirList() throws Exception {
     hdfsPathsLists = new ArrayList<>();
     getHdfsPaths(new Path("/"));
     for (String p : hdfsPathsLists) {
         System.err.println(p);
     }
 }
 private void getHdfsPaths(Path path) throws Exception {
     FileStatus[] dirs = fs.listStatus(path);
     for (FileStatus s : dirs) {
         hdfsPathsLists.add(s.getPath().toString());
         if (s.isDirectory()) {
             getHdfsPaths(s.getPath());
         }
     }
 }
 @Test
 public void testRMdir() throws Exception {
     boolean flag = fs.deleteOnExit(new Path("/java"));
     System.err.println(flag ? "success" : "fail");
 }
 @Test
 public void testexistsFile() throws Exception {
     String src = "hdfs://localhost:9000/README1.txt";
     boolean b = fs.exists(new Path(src));
     if (b) {
         System.err.println(b + " exist");
     } else {
         System.err.println(b + " not exist");
     }
 }
 @Test
 public void testfilesFile() throws Exception {
     String src = "hdfs://localhost:9000/README1.txt";
     boolean b = fs.isDirectory(new Path(src));
     if (b) {
         System.err.println("directories");
     } else if (fs.isFile(new Path(src))) {
         System.err.println("file");
     } else {
         System.err.println("I dont know");
     }
 }
 @Test
 public void testrenameFile() throws Exception {
     String oldpath = "hdfs://localhost:9000/README1.txt";
     String newpath = "hdfs://localhost:9000/shiyanbar.txt";
     Boolean b = fs.rename(new Path(oldpath), new Path(newpath));
     System.err.println(b + "rename  sucess");
 }
 @Test
 public void testmovetohdfsFile() throws Exception {
     String oldpath = "file:///simple/test/word.txt";
     String newpath = "hdfs://localhost:9000/user/";
     fs.moveFromLocalFile(new Path(oldpath), new Path(newpath));
     System.err.println("move success");
 }
 @Test
 public void testUploadFile() throws Exception {
     String src = "file:///simple/employees.txt";
     String hdfsDst = "/";
     fs.copyFromLocalFile(new Path(src), new Path(hdfsDst));
     System.err.println("upload  sucess");
 }
 @Test
 public void testDownloadFile() throws Exception {
     String src = "hdfs://localhost:9000/shiyanbar.txt";
     String local = "/data/dataset";
     fs.copyToLocalFile(new Path(src), new Path(local));
     System.err.println("downLoad  sucess");
 }
 @Test
 public void testMergelocalfiles() {
     try {
         Path inputDir = new Path("file:///opt/hadoop-2.7.3/etc/hadoop/");
         Path hdfsFile = new Path( "/output3");
         FileStatus[] inputFiles = local.listStatus(inputDir);
         FSDataOutputStream out = fs.create(hdfsFile);
         for (int i = 0; i < inputFiles.length; i++) {
             System.err.println(inputFiles[i].getPath().getName());
             FSDataInputStream in = local.open(inputFiles[i].getPath());
             byte[] buffer = new byte[256];
             int bytesRead = 0;
             while ((bytesRead = in.read(buffer)) > 0) {
                 out.write(buffer, 0, bytesRead);
             }
             in.close();
         }
         out.close();
     } catch (IOException e) {
         e.printStackTrace();
     }
 }
}