HDFs Java Client to the HDFs file additions and deletions to check and change

Step1: Increased dependency pom.xml ...     <!--Https://mvnrepository.com/artifact/org.apache.hadoop/hadoop-common --           <Dependency>                <groupId>Org.apache.hadoop</groupId>                <Artifactid> Hadoop-common</Artifactid>                <version>2.2.0</version>                <Exclusions>                     <exclusion>                           <Artifactid>Jdk.tools</Artifactid>                           <groupId>Jdk.tools</groupId>                     </exclusion>                </Exclusions>           </Dependency>           <Dependency>                <groupId>Org.apache.hadoop</groupId>                <Artifactid> Hadoop-HDFs </Artifactid>                <version>2.2.0</version>           </Dependency>Step2: Copy config file ' hdfs-site.xml ' and ' Core-site.xml ' step3: Test code

 PackageCjkjcn.demo.hadoop.hdfs;ImportJava.io.BufferedReader;Importjava.io.IOException;ImportJava.io.InputStreamReader;Importjava.util.LinkedList;Importjava.util.List;Importorg.apache.hadoop.conf.Configuration;ImportOrg.apache.hadoop.fs.FSDataInputStream;ImportOrg.apache.hadoop.fs.FileSystem;ImportOrg.apache.hadoop.fs.Path;/** * * @authorJunhong * * May 18, 2017*/ Public classHdfsdao {Private StaticConfiguration conf =NewConfiguration (); PrivateFileSystem HDFs; Final StaticString Root_path = "/user";  PublicHdfsdao () {Conf.addresource ("Hdfs-site.xml"); Conf.addresource ("Core-site.xml"); Try{HDFs= Filesystem.get (conf);//Initialize HDFs}Catch(IOException e) {e.printstacktrace (); } System.out.println ("Param size=" +conf.size ()); }     /*** Scan test file exists*/      Public voidScanfiles () {Try{path Path=NewPath (Root_path);           System.out.println (hdfs.exists (path)); } Catch(IOException e) {e.printstacktrace (); }     }     /*** Read text files by line *@paramfile *@return      */      PublicList<string>lines (String file) {List<String> list =NewLinkedlist<>(); Path F=NewPath (file); Try{Fsdatainputstream input=Hdfs.open (f); InputStreamReader INR=NewInputStreamReader (input); BufferedReader Read=NewBufferedReader (INR);                String Line;  while(line = Read.readline ())! =NULL) {List.add (line); }           } Catch(IOException e) {e.printstacktrace (); }           returnlist; }}

Note:1) If the lack of dependency<Dependency>                <groupId>Org.apache.hadoop</groupId>                <Artifactid> Hadoop-HDFs </Artifactid>                <version>2.2.0</version>           </Dependency>will cause the following error!! Java.io.Exception:No FileSystem for Scheme:hdfs2) Permission issues may occur when you test a write file or create a directory method interfacepemission denied for test

HDFs Java Client to the HDFs file additions and deletions to check and change