Comment 1 Doug Clarke 2010-06-28 13:14:09 EDT

Trying it with SIZE:

SELECT e FROM Employee e WHERE SIZE(e.responsibilities) > 0

gives me a similar NPE

Local Exception Stack: 
Exception [EclipseLink-6168] (Eclipse Persistence Services - 2.1.0.v20100614-r7608): org.eclipse.persistence.exceptions.QueryException
Exception Description: Query failed to prepare, unexpected error occurred: [java.lang.NullPointerException].
Internal Exception: java.lang.NullPointerException
Query: ReadAllQuery(referenceClass=Employee jpql="SELECT e FROM Employee e WHERE SIZE(e.responsibilities) > 0")
	at org.eclipse.persistence.exceptions.QueryException.prepareFailed(QueryException.java:1528)
	at org.eclipse.persistence.queries.DatabaseQuery.checkPrepare(DatabaseQuery.java:521)
	at org.eclipse.persistence.queries.ObjectLevelReadQuery.checkPrepare(ObjectLevelReadQuery.java:818)
	at org.eclipse.persistence.queries.DatabaseQuery.prepareCall(DatabaseQuery.java:1584)
	at org.eclipse.persistence.internal.jpa.EJBQueryImpl.buildEJBQLDatabaseQuery(EJBQueryImpl.java:266)
	at org.eclipse.persistence.internal.jpa.EJBQueryImpl.buildEJBQLDatabaseQuery(EJBQueryImpl.java:182)
	at org.eclipse.persistence.internal.jpa.EJBQueryImpl.<init>(EJBQueryImpl.java:134)
	at org.eclipse.persistence.internal.jpa.EJBQueryImpl.<init>(EJBQueryImpl.java:118)
	at org.eclipse.persistence.internal.jpa.EntityManagerImpl.createQuery(EntityManagerImpl.java:1352)
	at org.eclipse.persistence.internal.jpa.EntityManagerImpl.createQuery(EntityManagerImpl.java:1374)
	at example.Transactions.updateResponsibility(Transactions.java:133)
	at testing.TransactionTests.updateResponsibility(TransactionTests.java:89)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:44)
	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41)
	at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20)
	at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:31)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:76)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)
	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)
	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)
	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)
	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)
	at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:31)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
	at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:49)
	at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
Caused by: java.lang.NullPointerException
	at org.eclipse.persistence.internal.expressions.SubSelectExpression.normalizeSubSelect(SubSelectExpression.java:120)
	at org.eclipse.persistence.internal.expressions.ExpressionNormalizer.normalizeSubSelects(ExpressionNormalizer.java:93)
	at org.eclipse.persistence.internal.expressions.SQLSelectStatement.normalize(SQLSelectStatement.java:1373)
	at org.eclipse.persistence.internal.queries.ExpressionQueryMechanism.buildNormalSelectStatement(ExpressionQueryMechanism.java:491)
	at org.eclipse.persistence.internal.queries.ExpressionQueryMechanism.prepareSelectAllRows(ExpressionQueryMechanism.java:1553)
	at org.eclipse.persistence.queries.ReadAllQuery.prepareSelectAllRows(ReadAllQuery.java:678)
	at org.eclipse.persistence.queries.ReadAllQuery.prepare(ReadAllQuery.java:625)
	at org.eclipse.persistence.queries.DatabaseQuery.checkPrepare(DatabaseQuery.java:509)
	... 34 more

Comment 2 Guy Pelletier 2010-07-28 13:49:26 EDT

Deferring this bug to 2.2.0

In the mean time, the following JPQL can be used as an alternative:

Query query = em.createQuery("select e from Employee e where (SELECT count(e1.responsibilities) from Employee e1) > 0");

Comment 3 Tom Ware 2010-11-08 14:51:16 EST

Correct workaround looks more like this:

"select e from Employee e where (SELECT count(e1.responsibilities) from Employee e1 where e1.id = e.id) > 0"

Comment 4 Tom Ware 2010-11-15 09:59:44 EST

Created attachment 183122 [details]
proposed fix

Comment 5 Tom Ware 2010-11-15 14:43:41 EST

Created attachment 183152 [details]
Updated Patch

Comment 6 Tom Ware 2010-11-15 14:46:44 EST

Fixed in trunk.   The fix stores some information about the subquery and builds it when information about the session is available for subqueries involved in COUNT.

Reviewed by James Sutherland

Tested with JPA and Core LRG

Added 2 tests to JUnitJPQLSimpleTestSuite

Comment 7 Eclipse Webmaster 2022-06-09 10:08:20 EDT

The Eclipselink project has moved to Github: https://github.com/eclipse-ee4j/eclipselink