The Hortonworks Community Connection is now live. A completely rebuilt Q&A forum, Knowledge Base, Code Hub and more, backed by the experts in the industry.

You will be redirected here in 10 seconds. If your are not redirected, click here to visit the new site.

The legacy Hortonworks Forum is now closed. You can view a read-only version of the former site by clicking here. The site will be taken offline on January 31,2016

Hortonworks Sandbox Forum

Running simple Java job

  • #28538

    How do a run a simple Hadoop java job in the Sandbox?

    I’ve tried using using the java type Job Design but I get an error saying ClassNotFound HelloWorld. The myjob.jar file has the HelloWorld class in it.

    My settingings are
    Jar path /user/sample.myjob.jar
    Main class HelloWorld
    And my class is a trivial one that just sets the input file and output directory and uses the default mapper/reducer:

    import java.io.IOException;
    import org.apache.hadoop.mapreduce.Job;
    import org.apache.hadoop.fs.Path;
    import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
    import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
    import org.apache.hadoop.io.Text;

    public class HelloWorld {

    public static void main( String [] args ) throws IOException, ClassNotFoundException, InterruptedException {
    // TODO Auto-generated method stub
    @SuppressWarnings (“unused” )
    Job job = new Job ();
    FileInputFormat.addInputPath (job, new Path( “/user/sample/trivialdata.txt” ));
    FileOutputFormat.setOutputPath (job, new Path( “/user/sample/otest1”)) ;
    job.setOutputKeyClass (Text. class) ;
    job.setOutputValueClass (Text. class) ;
    System.exit (job.waitForCompletion ( true) ? 0 : 1 ) ;
    }
    }

    Thanks,
    Dan

  • Author
    Replies
  • #44978
    Xiandong Su
    Member

    I do not know if you have resolved this issue. If not, try to put the class in a package. I copied your code without any changes, except a package information. Running it on Hortonworks platform, and it ran through without any problems. When specifying main class, you need to have package in it. For exmaple: org.something.HelloWorld

The forum ‘Hortonworks Sandbox’ is closed to new topics and replies.

Support from the Experts

A HDP Support Subscription connects you experts with deep experience running Apache Hadoop in production, at-scale on the most demanding workloads.

Enterprise Support »

Become HDP Certified

Real world training designed by the core architects of Hadoop. Scenario-based training courses are available in-classroom or online from anywhere in the world

Training »

Hortonworks Data Platform
The Hortonworks Data Platform is a 100% open source distribution of Apache Hadoop that is truly enterprise grade having been built, tested and hardened with enterprise rigor.
Get started with Sandbox
Hortonworks Sandbox is a self-contained virtual machine with Apache Hadoop pre-configured alongside a set of hands-on, step-by-step Hadoop tutorials.
Modern Data Architecture
Tackle the challenges of big data. Hadoop integrates with existing EDW, RDBMS and MPP systems to deliver lower cost, higher capacity infrastructure.