Node getBaseVersion causes Exception after node removal

[alexpanov]

When a versioned node gets removed it still can be found by identifier (should it be?).
More importantly node.getBaseVersion() causes UnsupportedRepositoryOperationException like this:
javax.jcr.UnsupportedRepositoryOperationException: This operation requires that the node be versionable (that is, isNodeType("mix:versionable") == true)
at org.modeshape.jcr.AbstractJcrNode.getBaseVersion(AbstractJcrNode.java:3264)
at org.modeshape.jcr.JcrSystemNode.getBaseVersion(JcrSystemNode.java:33)
at org.modeshape.jcr.GetBaseVersionAfterNodeRemovalTest.testName(GetBaseVersionAfterNodeRemovalTest.java:37)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:45)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:42)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:28)
at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:30)
at org.junit.rules.RunRules.evaluate(RunRules.java:18)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:263)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:68)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:47)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:231)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:60)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:229)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:50)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:222)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:28)
at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:30)
at org.junit.runners.ParentRunner.run(ParentRunner.java:300)
at org.junit.runner.JUnitCore.run(JUnitCore.java:157)
at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:77)
at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:195)
at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:63)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:120)

[hchiorean]

Because a versionable node should be able to be restored even if removed, ModeShape uses the same ID to store the version history of the node. Even after the node is removed, the versionHistory still exists.

Therefore, when performing a session.getNodeByIdentifier after the node has been removed, ModeShape will return the versionHistory for that node which explains the reason for the exception - you should not be allowed to call getBaseVersion on a versionHistory instance.

IMO this is not a bug, but rather an invalid versioning usage scenario.

@rhauch thoughts ?

[alexpanov]

I could argue that it is not a good thing that accessing removed node is done with the same method that one regularly retrieves them with, but at least the message is very misleading.

[hchiorean]

According to the spec javadoc from getBaseVersion():

   @throws UnsupportedRepositoryOperationException  if this node is not versionable

[hchiorean]

@madmeat can you please open a JIRA issue and attach this PR to it ?

It's unclear atm. what the exact issue you're reporting is: is it the exception message, the fact that getNodeByIdentifier() retrieves the node or something else. It can be argued that the getNodeByIdentifier() should not return a version history.

Thanks

[hchiorean]

@madmeat: I've opened https://issues.jboss.org/browse/MODE-2055 and we will fix the behavior of session.getNodeByIdentifier

[hchiorean]

Closing, as this issue has been addressed in #956