[ https://issues.apache.org/jira/browse/PIG-2827?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13418164#comment-13418164 ]
Haitao Yao commented on PIG-2827: --------------------------------- the modified stacktrace should be like this: java.lang.RuntimeException: General Exception executing function: at org.apache.pig.builtin.TOP.exec(TOP.java:133) at org.apache.pig.builtin.TOP.exec(TOP.java:1) at org.apache.pig.backend.hadoop.executionengine.physicalLayer.expressionOperators.POUserFunc.getNext(POUserFunc.java:216) at org.apache.pig.backend.hadoop.executionengine.physicalLayer.expressionOperators.POUserFunc.getNext(POUserFunc.java:258) at org.apache.pig.backend.hadoop.executionengine.physicalLayer.PhysicalOperator.getNext(PhysicalOperator.java:316) at org.apache.pig.backend.hadoop.executionengine.physicalLayer.relationalOperators.POForEach.processPlan(POForEach.java:332) at org.apache.pig.backend.hadoop.executionengine.physicalLayer.relationalOperators.POForEach.getNext(POForEach.java:284) at org.apache.pig.backend.hadoop.executionengine.physicalLayer.PhysicalOperator.processInput(PhysicalOperator.java:290) at org.apache.pig.backend.hadoop.executionengine.physicalLayer.relationalOperators.POLimit.getNext(POLimit.java:85) at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigGenericMapReduce$Reduce.runPipeline(PigGenericMapReduce.java:460) at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigGenericMapReduce$Reduce.processOnePackageOutput(PigGenericMapReduce.java:428) at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigGenericMapReduce$Reduce.reduce(PigGenericMapReduce.java:408) at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigGenericMapReduce$Reduce.reduce(PigGenericMapReduce.java:1) at org.apache.hadoop.mapreduce.Reducer.run(Reducer.java:176) at org.apache.hadoop.mapred.ReduceTask.runNewReducer(ReduceTask.java:650) at org.apache.hadoop.mapred.ReduceTask.run(ReduceTask.java:418) at org.apache.hadoop.mapred.Child$4.run(Child.java:255) at java.security.AccessController.doPrivileged(Native Method) at javax.security.auth.Subject.doAs(Subject.java:415) at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1131) at org.apache.hadoop.mapred.Child.main(Child.java:249) Caused by: java.lang.NullPointerException at org.apache.pig.data.DataType.compare(DataType.java:427) at org.apache.pig.builtin.TOP$TupleComparator.compare(TOP.java:97) at org.apache.pig.builtin.TOP$TupleComparator.compare(TOP.java:1) at java.util.PriorityQueue.siftUpUsingComparator(PriorityQueue.java:649) at java.util.PriorityQueue.siftUp(PriorityQueue.java:627) at java.util.PriorityQueue.offer(PriorityQueue.java:329) at java.util.PriorityQueue.add(PriorityQueue.java:306) at org.apache.pig.builtin.TOP.updateTop(TOP.java:141) at org.apache.pig.builtin.TOP.exec(TOP.java:116) ... 20 more > TOP exception bug > ----------------- > > Key: PIG-2827 > URL: https://issues.apache.org/jira/browse/PIG-2827 > Project: Pig > Issue Type: Bug > Reporter: Haitao Yao > Attachments: TOP.patch > > > the current exception will swallow the inner exception's stacktrace like this: > java.lang.RuntimeException: General Exception executing function: > java.lang.NullPointerException > at org.apache.pig.builtin.TOP.exec(TOP.java:133) > at org.apache.pig.builtin.TOP.exec(TOP.java:1) > at > org.apache.pig.backend.hadoop.executionengine.physicalLayer.expressionOperators.POUserFunc.getNext(POUserFunc.java:216) > at > org.apache.pig.backend.hadoop.executionengine.physicalLayer.expressionOperators.POUserFunc.getNext(POUserFunc.java:258) > at > org.apache.pig.backend.hadoop.executionengine.physicalLayer.PhysicalOperator.getNext(PhysicalOperator.java:316) > at > org.apache.pig.backend.hadoop.executionengine.physicalLayer.relationalOperators.POForEach.processPlan(POForEach.java:332) > at > org.apache.pig.backend.hadoop.executionengine.physicalLayer.relationalOperators.POForEach.getNext(POForEach.java:284) > at > org.apache.pig.backend.hadoop.executionengine.physicalLayer.PhysicalOperator.processInput(PhysicalOperator.java:290) > at > org.apache.pig.backend.hadoop.executionengine.physicalLayer.relationalOperators.POForEach.getNext(POForEach.java:233) > at > org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigGenericMapReduce$Reduce.runPipeline(PigGenericMapReduce.java:460) > at > org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigGenericMapReduce$Reduce.processOnePackageOutput(PigGenericMapReduce.java:428) > at > org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigGenericMapReduce$Reduce.reduce(PigGenericMapReduce.java:408) > at > org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigGenericMapReduce$Reduce.reduce(PigGenericMapReduce.java:1) > at org.apache.hadoop.mapreduce.Reducer.run(Reducer.java:176) > at > org.apache.hadoop.mapred.ReduceTask.runNewReducer(ReduceTask.java:650) > at org.apache.hadoop.mapred.ReduceTask.run(ReduceTask.java:418) > at org.apache.hadoop.mapred.Child$4.run(Child.java:255) > at java.security.AccessController.doPrivileged(Native Method) > at javax.security.auth.Subject.doAs(Subject.java:415) > at > org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1131) > at org.apache.hadoop.mapred.Child.main(Child.java:249) > we can not locate the real errors. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa For more information on JIRA, see: http://www.atlassian.com/software/jira