[
https://issues.apache.org/jira/browse/DRILL-6234?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16397856#comment-16397856
]
Timothy Farkas commented on DRILL-6234:
---------------------------------------
Hi [~paul-rogers], I agree with your analysis. What I tried doing was having
the vector remember it's value count without being explicitly told it. In the
case of variable length vectors the value count is effectively last index
written to + 1. If someone set a larger value count we would simply increase
the size of the offset vector but internally use the last written index + 1 as
the effective value count. If someone sets a smaller value count than the
current, then we trim the vector as the method does now. I got things to work
as I wanted in isolation, but things broke down in the integration tests when
transferTo, load, and getMetadata were called. Then I realized how pointless
this whole thing was and you were right all along :) and gave up. I'm going to
salvage some of the Javadoc and unit tests I wrote and supplement it with some
of your explanation in an effort to prevent other people from being confused by
this. I'll open a small PR with the documentation improvements and tag you on
it.
> VarCharVector setValueCount can throw IndexOutOfBoundsException
> ---------------------------------------------------------------
>
> Key: DRILL-6234
> URL: https://issues.apache.org/jira/browse/DRILL-6234
> Project: Apache Drill
> Issue Type: Improvement
> Reporter: Timothy Farkas
> Assignee: Timothy Farkas
> Priority: Major
>
> Doing the following will throw an Index out of bounds exception.
> {code}
> final VarCharVector vector = new VarCharVector(field, allocator);
> vector.allocateNew();
> vector.getMutator().setValueCount(100);
> {code}
> The expected behavior is to resize the array appropriately. If an index is
> uninitialized you should not call get for that index.
> {code}
> at
> org.apache.drill.exec.memory.BoundsChecking.checkIndex(BoundsChecking.java:80)
> at
> org.apache.drill.exec.memory.BoundsChecking.lengthCheck(BoundsChecking.java:86)
> at io.netty.buffer.DrillBuf.chk(DrillBuf.java:114)
> at io.netty.buffer.DrillBuf.getInt(DrillBuf.java:484)
> at
> org.apache.drill.exec.vector.UInt4Vector$Accessor.get(UInt4Vector.java:432)
> at
> org.apache.drill.exec.vector.VarCharVector$Mutator.setValueCount(VarCharVector.java:729)
> at
> org.apache.drill.exec.vector.VarCharVectorTest.testExpandingNonEmptyVectorSetValueCount(VarCharVectorTest.java:97)
> at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
> at java.lang.reflect.Method.invoke(Method.java:606)
> at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
> at java.lang.reflect.Method.invoke(Method.java:606)
> at
> com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
> at
> com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
> at
> com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
> at
> com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)
> {code}
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
