提醒：如果要在idear或者eclipse等IDE下运行就必须在HDFS上给你所使用的目录分配权限给windows下的用户，为了方便起见建议给所有权限777
创建目录命令
hdfs dfs -mkdir myproject
分配权限命令 hdfs dfs -chmod 777 myproject HDFS增删改查工具类 package hdfs; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.FileStatus; import org.apache.hadoop.fs.FileSystem; import org.apache.hadoop.fs.Path; import java.io.IOException; import java.util.ArrayList; import java.util.List; /** * Created by LiuwenSheng on 2017/8/7. */ public class HDFSUtils { private final String FILE_PROTOCOL = "file:///"; private final String HDFS_PROTOCOL = "hdfs://xxx:9000/myproject";//此处xxx表示你的IP地址比如：192.168.18.1 /** * 用于从本地文件中选择文件上传至hdfs中 * @param conf org.apache.hadoop.conf.Configuration 配置信息 * @param localPath String 本地文件的存储路径 * @param hdfsPath String 上传到HDFS的路径 eg:/a/b.txt * @throws IOException */ public void file2HDFS( Configuration conf,String localPath,String hdfsPath)throws IOException{ FileSystem fs = FileSystem.get(conf); fs.copyFromLocalFile(new Path(FILE_PROTOCOL+localPath),new Path(HDFS_PROTOCOL+hdfsPath)); fs.close(); } /** * 测试文件是否存在 * @param conf 配置信息 * @param path 文件路径 * @return * @throws IOException */ public boolean isExit(Configuration conf,String path)throws IOException{ FileSystem fs = FileSystem.get(conf); boolean exit = fs.exists(new Path(HDFS_PROTOCOL+path)); fs.close(); return exit; } /** * 删除文件 * @param conf org.apache.hadoop.conf.Configuration 配置信息 * @param path 要删除的文件路径 * @throws IOException */ public Boolean deleteFormHDFS(Configuration conf,String path) throws IOException { FileSystem fs = FileSystem.get(conf); boolean isDel = fs.deleteOnExit(new Path(HDFS_PROTOCOL+path)); fs.close(); return isDel; } /** * 把HDFS上面的文件下载到本地 * @param conf 配置信息 * @param hdfsPath hdfs的文件路径 * @param localPath 本地文件路径 * @throws IOException */ public void file2Loacl(Configuration conf,String hdfsPath,String localPath)throws IOException{ FileSystem fs = FileSystem.get(conf); fs.copyToLocalFile(new Path(HDFS_PROTOCOL+hdfsPath),new Path(FILE_PROTOCOL+localPath)); fs.close(); } /** * 创建hdfs目录 * @param conf 配置信息 * @param path 需要创建的目录路径 * @return 是否创建成功 * @throws IOException */ public Boolean mkHDFSDir(Configuration conf,String path)throws IOException{ FileSystem fs = FileSystem.get(conf); Path mypath = new Path(HDFS_PROTOCOL + path); boolean ismk = false; if(!fs.exists(mypath)) { ismk = fs.mkdirs(mypath); } fs.close(); return ismk; } /** * 查看当前目录内文件列表 * @param conf 配置信息 * @param path 查看的目录 * @return 文件状态数组 * @throws IOException */ public List lsHDFSDir(Configuration conf, String path) throws IOException{ List list = new ArrayList(); FileSystem fs = FileSystem.get(conf); FileStatus[] fileStatuses = fs.listStatus(new Path(HDFS_PROTOCOL + path)); for (FileStatus fileStatus:fileStatuses){ list.add(fileStatus.getPath().toString()); } fs.close(); return list; } } 测试用例 package test; import hdfs.HDFSUtils; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.FileStatus; import org.junit.Before; import org.junit.Test; import javax.ws.rs.core.Context; import java.io.IOException; import java.util.List; /** * Created by lws on 2017/8/7. */ public class MyHDFSTest { private HDFSUtils hdfsUtils = new HDFSUtils(); private Configuration conf = new Configuration(); @Before public void beforeBegining(){ conf.set("fs.defaultFS", "hdfs://xxx:9000/");//此处xxx为你的IP地址，如192.168.12.8 } @Test public void test_file2HDFS()throws IOException{ hdfsUtils.file2HDFS(conf,"D:\\BugReport.txt","/myuser2/1"); } @Test public void test_deleteFormHDFS()throws IOException{ hdfsUtils.deleteFormHDFS(conf,"/myuser/BugReport.txt"); } @Test public void test_isExit()throws IOException{ boolean is = hdfsUtils.isExit(conf,"/myuser/BugReport.txt"); System.out.print(is); } @Test public void test_file2Local()throws IOException{ hdfsUtils.file2Loacl(conf,"/myuser/BugReport.txt","D://test"); } @Test public void test_mkHDFSDir()throws IOException{ boolean a = hdfsUtils.mkHDFSDir(conf,"/myuser/liming"); System.out.print(a); } @Test public void test_lsHDFSDir()throws IOException{ List list = hdfsUtils.lsHDFSDir(conf,"/myuser2"); for (String file:list){ System.out.println(file); } } }