"Hadoop"--modifying Hadoop Fileutil.java To resolve permissions check issues

in the Hadoop Eclipse Development Environment Building In this article, the 15th.) mentions permission-related exceptions, as follows:

15/01/30 10:08:17 WARN util. nativecodeloader:unable to load Native-hadoop library for your platform ... using Builtin-java classes where applicable15/ 01/30 10:08:17 ERROR Security. Usergroupinformation:priviledgedactionexception As:zhangchao3 cause:java.io.IOException:Failed to set permissions of Path: \tmp\hadoop-zhangchao3\mapred\staging\zhangchao3502228304\.staging to 0700Exception in thread "main" Java.io.IOException:Failed to set permissions of path: \tmp\hadoop-zhangchao3\mapred\staging\zhangchao3502228304\. Staging to 0700 atOrg.apache.hadoop.fs.FileUtil.checkReturnValue (fileutil.java:689)    At Org.apache.hadoop.fs.FileUtil.setPermission (fileutil.java:662) at Org.apache.hadoop.fs.RawLocalFileSystem.setPermission (rawlocalfilesystem.java:509) at Org.apache.hadoop.fs.RawLocalFileSystem.mkdirs (rawlocalfilesystem.java:344) at Org.apache.hadoop.fs.FilterFileSystem.mkdirs (filterfilesystem.java:189) at Org.apache.hadoop.mapreduce.JobSubmissionFiles.getStagingDir (jobsubmissionfiles.java:116) at Org.apache.hadoop.mapred.jobclient$2.run (jobclient.java:856) at Org.apache.hadoop.mapred.jobclient$2.run ( jobclient.java:850) at java.security.AccessController.doPrivileged (Native Method) at javax.security.auth.Subject.do As (subject.java:415) at Org.apache.hadoop.security.UserGroupInformation.doAs (usergroupinformation.java:1121) at Org.apache.hadoop.mapred.JobClient.submitJobInternal (jobclient.java:850) at Org.apache.hadoop.mapreduce.Job.submit (job.java:500) at Org.apache.hadoop.mapreduce.Job.waitForCompletion ( job.java:530) at Org.apache.hadoop.examplEs. Wordcount.main (wordcount.java:68)

According to the prompt information, you can see that this exception is Org.apache.hadoop.fs.FileUtil.checkReturnValue (fileutil.java:689) line thrown out, the source code of this location to paste out, study:

private static void Checkreturnvalue (Boolean rv, File p,                                        fspermission permission                                       ) throws IOException {    if (! RV) {      throw new IOException ("Failed to set permissions of path:" + P +                             "to" +                             String.Format ("%04o", Permiss Ion.toshort ()));    }  }

In the above exception information, the fileutil.java:689 line is the throw new IOException ("Failed to ..., I will directly remove the IF statement of this function, as follows:

private static void Checkreturnvalue (Boolean rv, File p, fspermission permission)    throws IOException  {}

In this way, Chekreturnvalue becomes an empty function so that permissions are not checked, executed in/home/hadoop/hadoop-1.0.3/, the Ant Jar is compiled, and problems that may be encountered in the compilation are as follows: compiling Hadoop encounters maven Timeout, after compiling, generate the following file:

Copy the generated Hadoop-core-1.0.4-snapshot.jar file to Windows and use Java decoder to see that the Checkreturnvalue has been modified:

Change the Hadoop-core-1.0.4-snapshot.jar to Hadoop-core-1.0.3.jar file, overwriting the Hadoop-core-1.0.3.jar file in the Eclipse project:

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rerun run on Hadoop and it will run successfully. (How to execute run on Hadoop see:Hadoop Eclipse Development Environment Build 11 section)

Modified JAR Package: http://download.csdn.net/download/uestczhangchao/8420249

"Hadoop"--modifying Hadoop Fileutil.java To resolve permissions check issues