java.lang.NullPointerException

Pentaho BI Platform Tracking | Chris Deptula | 5 years ago
  1. 0

    If no data is output to the Map/Reduce Output step as part of a reducer the job fails with a null pointer exception. This can happen if someone accidentally runs the job against an input directory with no data in it, if there is a filter in the mapper or reducer to only process certain records and no records meet the filter criteria, and many other use cases. When running a job with multiple reducers this can cause some reducers with data in them to fail to execute as they may never get kicked off. Easiest way to replicate is to run any Map/Reduce job against an input directory with no data in it. 2012/01/24 15:27:11 - Pentaho MapReduce - ERROR (version 4.3.0, build 16231 from 2012-01-18 12.34.54 by tomcat) : [FAILED] -- Task: 0 Attempt: 2 Event: 3 2012/01/24 15:27:11 - Pentaho MapReduce - ERROR (version 4.3.0, build 16231 from 2012-01-18 12.34.54 by tomcat) : java.lang.NullPointerException 2012/01/24 15:27:11 - Pentaho MapReduce - ERROR (version 4.3.0, build 16231 from 2012-01-18 12.34.54 by tomcat) : at org.pentaho.hadoop.mapreduce.GenericTransReduce.close(GenericTransReduce.java:346) 2012/01/24 15:27:11 - Pentaho MapReduce - ERROR (version 4.3.0, build 16231 from 2012-01-18 12.34.54 by tomcat) : at org.apache.hadoop.mapred.ReduceTask.runOldReducer(ReduceTask.java:479) 2012/01/24 15:27:11 - Pentaho MapReduce - ERROR (version 4.3.0, build 16231 from 2012-01-18 12.34.54 by tomcat) : at org.apache.hadoop.mapred.ReduceTask.run(ReduceTask.java:417) 2012/01/24 15:27:11 - Pentaho MapReduce - ERROR (version 4.3.0, build 16231 from 2012-01-18 12.34.54 by tomcat) : at org.apache.hadoop.mapred.Child$4.run(Child.java:270) 2012/01/24 15:27:11 - Pentaho MapReduce - ERROR (version 4.3.0, build 16231 from 2012-01-18 12.34.54 by tomcat) : at java.security.AccessController.doPrivileged(Native Method) 2012/01/24 15:27:11 - Pentaho MapReduce - ERROR (version 4.3.0, build 16231 from 2012-01-18 12.34.54 by tomcat) : at javax.security.auth.Subject.doAs(Subject.java:396) 2012/01/24 15:27:11 - Pentaho MapReduce - ERROR (version 4.3.0, build 16231 from 2012-01-18 12.34.54 by tomcat) : at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1127) 2012/01/24 15:27:11 - Pentaho MapReduce - ERROR (version 4.3.0, build 16231 from 2012-01-18 12.34.54 by tomcat) : at org.apache.hadoop.mapred.Child.main(Child.java:264)

    Pentaho BI Platform Tracking | 5 years ago | Chris Deptula
    java.lang.NullPointerException
  2. 0

    If no data is output to the Map/Reduce Output step as part of a reducer the job fails with a null pointer exception. This can happen if someone accidentally runs the job against an input directory with no data in it, if there is a filter in the mapper or reducer to only process certain records and no records meet the filter criteria, and many other use cases. When running a job with multiple reducers this can cause some reducers with data in them to fail to execute as they may never get kicked off. Easiest way to replicate is to run any Map/Reduce job against an input directory with no data in it. 2012/01/24 15:27:11 - Pentaho MapReduce - ERROR (version 4.3.0, build 16231 from 2012-01-18 12.34.54 by tomcat) : [FAILED] -- Task: 0 Attempt: 2 Event: 3 2012/01/24 15:27:11 - Pentaho MapReduce - ERROR (version 4.3.0, build 16231 from 2012-01-18 12.34.54 by tomcat) : java.lang.NullPointerException 2012/01/24 15:27:11 - Pentaho MapReduce - ERROR (version 4.3.0, build 16231 from 2012-01-18 12.34.54 by tomcat) : at org.pentaho.hadoop.mapreduce.GenericTransReduce.close(GenericTransReduce.java:346) 2012/01/24 15:27:11 - Pentaho MapReduce - ERROR (version 4.3.0, build 16231 from 2012-01-18 12.34.54 by tomcat) : at org.apache.hadoop.mapred.ReduceTask.runOldReducer(ReduceTask.java:479) 2012/01/24 15:27:11 - Pentaho MapReduce - ERROR (version 4.3.0, build 16231 from 2012-01-18 12.34.54 by tomcat) : at org.apache.hadoop.mapred.ReduceTask.run(ReduceTask.java:417) 2012/01/24 15:27:11 - Pentaho MapReduce - ERROR (version 4.3.0, build 16231 from 2012-01-18 12.34.54 by tomcat) : at org.apache.hadoop.mapred.Child$4.run(Child.java:270) 2012/01/24 15:27:11 - Pentaho MapReduce - ERROR (version 4.3.0, build 16231 from 2012-01-18 12.34.54 by tomcat) : at java.security.AccessController.doPrivileged(Native Method) 2012/01/24 15:27:11 - Pentaho MapReduce - ERROR (version 4.3.0, build 16231 from 2012-01-18 12.34.54 by tomcat) : at javax.security.auth.Subject.doAs(Subject.java:396) 2012/01/24 15:27:11 - Pentaho MapReduce - ERROR (version 4.3.0, build 16231 from 2012-01-18 12.34.54 by tomcat) : at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1127) 2012/01/24 15:27:11 - Pentaho MapReduce - ERROR (version 4.3.0, build 16231 from 2012-01-18 12.34.54 by tomcat) : at org.apache.hadoop.mapred.Child.main(Child.java:264)

    Pentaho BI Platform Tracking | 5 years ago | Chris Deptula
    java.lang.NullPointerException
  3. 0

    Android: Saving Map State in Google map

    Stack Overflow | 11 months ago | Junie Negentien
    java.lang.RuntimeException: Unable to resume activity {com.ourThesis.junieNegentien2015/com.ourThesis.junieNegentien2015.MainActivity}: java.lang.NullPointerException
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    Root Cause Analysis

    1. java.lang.NullPointerException

      No message provided

      at org.pentaho.hadoop.mapreduce.GenericTransReduce.close()
    2. org.pentaho.hadoop
      GenericTransReduce.close
      1. org.pentaho.hadoop.mapreduce.GenericTransReduce.close(GenericTransReduce.java:346)
      1 frame
    3. Hadoop
      Child$4.run
      1. org.apache.hadoop.mapred.ReduceTask.runOldReducer(ReduceTask.java:479)
      2. org.apache.hadoop.mapred.ReduceTask.run(ReduceTask.java:417)
      3. org.apache.hadoop.mapred.Child$4.run(Child.java:270)
      3 frames
    4. Java RT
      Subject.doAs
      1. java.security.AccessController.doPrivileged(Native Method)
      2. javax.security.auth.Subject.doAs(Subject.java:396)
      2 frames
    5. Hadoop
      UserGroupInformation.doAs
      1. org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1127)
      1 frame
    6. Hadoop
      Child.main
      1. org.apache.hadoop.mapred.Child.main(Child.java:264)
      1 frame