[DERBY-5726] Make it more difficult to forget calling super.tearDown() from BaseJDBCTestCase's subclasses

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 10.9.1.0
• Fix Version/s: 10.9.1.0
• Component/s: Test
• Assignee: Knut Anders Hatlen
• Reporter: Knut Anders Hatlen
• Created: 25/Apr/12 12:46
• Updated: 24/Jul/12 17:28
• Resolved: 02/May/12 09:35

Description

Many of the classes that extend BaseJDBCTestCase and override the tearDown() method, forget to call super.tearDown(), and thereby prevent resources from being freed after completion. We should add a mechanism that enforces the correct behaviour.

If we were starting from scratch, we might have made BaseJDBCTestCase.tearDown() final and added a new overridable method that was called from BaseJDBCTestCase.tearDown() before it freed the statements and connections. Then there would be no way to prevent BaseJDBCTestCase.tearDown() from running in the subclasses. That would however require us to change all existing overrides of BaseJDBCTestCase.tearDown() (current count: 131), which would be a chunk of work.

I'd rather suggest that we add an override of runBare() in BaseJDBCTestCase that asserts that the connection has been cleared out when a test case has completed successfully. Something like this:

public void runBare() throws Throwable

{ super.runBare(); // It's quite common to forget to call super.tearDown() when // overriding tearDown() in sub-classes. assertNull( "Connection should be null by now. " + "Missing call to super.tearDown()?", conn); }

Then it would still be possible to forget to call super.tearDown(), but it would be discovered when trying to run the test.

Adding the above method to BaseJDBCTestCase and running InternationalConnectTest gave this result:

.....F.F....F
Time: 5,748
There were 3 failures:
1) testDriverManagerConnect(org.apache.derbyTesting.functionTests.tests.jdbcapi.InternationalConnectTest)junit.framework.AssertionFailedError: Connection should be null by now. Missing call to super.tearDown()?
at org.apache.derbyTesting.junit.BaseJDBCTestCase.runBare(BaseJDBCTestCase.java:431)
at junit.extensions.TestDecorator.basicRun(TestDecorator.java:24)
at junit.extensions.TestSetup$1.protect(TestSetup.java:21)
at junit.extensions.TestSetup.run(TestSetup.java:25)
at org.apache.derbyTesting.junit.BaseTestSetup.run(BaseTestSetup.java:57)
2) testBoundaries(org.apache.derbyTesting.functionTests.tests.jdbcapi.InternationalConnectTest)junit.framework.AssertionFailedError: Connection should be null by now. Missing call to super.tearDown()?
at org.apache.derbyTesting.junit.BaseJDBCTestCase.runBare(BaseJDBCTestCase.java:431)
(...)

Issue Links

• is blocked by: DERBY-5710 BigDataTest.tearDown() doesn't call super.tearDown()
• is blocked by: DERBY-5711 NullsTest doesn't call super.tearDown()
• is blocked by: DERBY-5718 UniqueConstraintSetNullTest calls super.tearDown() too early
• is blocked by: DERBY-5719 UniqueConstraintMultiThreadedTest doesn't call super.tearDown()
• is blocked by: DERBY-5720 UngroupedAggregatesNegativeTest doesn't call super.tearDown()
• is blocked by: DERBY-5721 ParameterMappingTest lacks call to super.tearDown()
• is blocked by: DERBY-5722 InternationalConnectTest forgets to call super.tearDown()
• is blocked by: DERBY-5723 LongColumnTest doesn't call super.tearDown()
• is blocked by: DERBY-5725 ErrorStreamTest doesn't call super.tearDown()