[FLINK-4100] RocksDBStateBackend#close() can throw NPE

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 1.1.0
• Fix Version/s: 1.1.3, 1.2.0
• Component/s: Runtime / State Backends, Tests
• Assignee: Unassigned
• Reporter: Chesnay Schepler
• Created: 22/Jun/16 10:48
• Updated: 13/Apr/21 20:41
• Resolved: 28/Nov/16 10:34

Description

When running the RocksDBStateBackendTest on Windows i ran into an NPE. The tests are aborted in the @Before checkOperatingSystem method (which is correct behaviour), but the test still calls dispose() in @After teardown().

This lead to an NPE since the lock object used is null; it was not initialized since initializeForJob() was never called and there is no null check.

testCopyDefaultValue(org.apache.flink.contrib.streaming.state.RocksDBStateBackendTest)  Time elapsed: 0 sec  <<< ERROR!
java.lang.NullPointerException: null
        at org.apache.flink.contrib.streaming.state.RocksDBStateBackend.dispose(RocksDBStateBackend.java:318)
        at org.apache.flink.runtime.state.StateBackendTestBase.teardown(StateBackendTestBase.java:71)
        at sun.reflect.GeneratedMethodAccessor2.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)
        at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
        at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)
        at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:33)
        at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)
        at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)
        at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
        at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
        at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
        at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
        at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
        at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
        at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
        at org.apache.maven.surefire.junit4.JUnit4Provider.execute(JUnit4Provider.java:283)
        at org.apache.maven.surefire.junit4.JUnit4Provider.executeWithRerun(JUnit4Provider.java:173)
        at org.apache.maven.surefire.junit4.JUnit4Provider.executeTestSet(JUnit4Provider.java:153)
        at org.apache.maven.surefire.junit4.JUnit4Provider.invoke(JUnit4Provider.java:128)
        at org.apache.maven.surefire.booter.ForkedBooter.invokeProviderInSameClassLoader(ForkedBooter.java:203)
        at org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:155)
        at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:103)