NoResultException and NonUniqueResultException are not thrown when expected

• Key: OPENJPA-208
• Type: Bug
• Status: Resolved
• Resolution: Fixed
• Priority: Major
• Assignee: Marc Prud'hommeaux
• Reporter: Marc Prud'hommeaux
• Component/s: jpa
• Affects Version/s: 0.9.6
• Fix Version/s: 0.9.7

Description

When calling Query.getSingleResult() on a query that either has no result or multiple results, either a NoResultException and NonUniqueResultException (respectively) should be thrown in accordance with section 3.6.1 of the JPA spec. Instead, we appear to throw a org.apache.openjpa.persistence.InvalidStateException:

org.apache.openjpa.persistence.InvalidStateException: The query on candidate type "class com.sun.ts.tests.ejb30.persistence.query.apitests.Department" with filter "select d.name from Department d where d.id > 1" was configured to have a unique result, but more than one instance matched the query.
     at org.apache.openjpa.kernel.QueryImpl.singleResult(QueryImpl.java:1282)
     at org.apache.openjpa.kernel.QueryImpl.toResult(QueryImpl.java:1207)
     at org.apache.openjpa.kernel.QueryImpl.execute(QueryImpl.java:982)
     at org.apache.openjpa.kernel.QueryImpl.execute(QueryImpl.java:791)
     at org.apache.openjpa.kernel.QueryImpl.execute(QueryImpl.java:761)
     at org.apache.openjpa.kernel.QueryImpl.execute(QueryImpl.java:757)
     at org.apache.openjpa.kernel.DelegatingQuery.execute(DelegatingQuery.java:514)
     at org.apache.openjpa.persistence.QueryImpl.execute(QueryImpl.java:225)
     at org.apache.openjpa.persistence.QueryImpl.getSingleResult(QueryImpl.java:287)

Comments

This seems to have slipped in in the fix for OPENJPA-168: see http://svn.apache.org/viewvc/incubator/openjpa/trunk/openjpa-persistence/src/main/java/org/apache/openjpa/persistence/QueryImpl.java?p2=%2Fincubator%2Fopenjpa%2Ftrunk%2Fopenjpa-persistence%2Fsrc%2Fmain%2Fjava%2Forg%2Fapache%2Fopenjpa%2Fpersistence%2FQueryImpl.java&p1=%2Fincubator%2Fopenjpa%2Ftrunk%2Fopenjpa-persistence%2Fsrc%2Fmain%2Fjava%2Forg%2Fapache%2Fopenjpa%2Fpersistence%2FQueryImpl.java&r1=522581&r2=522580&view=diff&pathrev=522581

[Marc Prud'hommeaux]

This appears to have been introduced by the commits for the fix for OPENJPA-168.

[Marc Prud'hommeaux]

The change to OPENJPA-168 seems to have been done to make the validation of a single result a little cleaner by having the kernel query perform the validation that there is a single result. However, this meant that we could only do generic exception translation, and so were no longer throwing a NoResultException or NonUniqueResultException. We could fix this by introducing a could new kernel exceptions or exception types, but it might just be easier to revert to having the validation done in the persistence QueryImpl.

Any objections to fixing this the easy way?

[Marc Prud'hommeaux]

Went ahead and restored the previous behavior where the QueryImpl itself checks for non-uniqueness and throws the expected exception.

[Marc Prud'hommeaux]

From Abe on mailing list: That breaks the single result optimization that was added for OPENJPA-168 when getSingleResult() is called. There was a reason we moved the validation to the kernel. The previous code was correct. You need to use the "hard" way of creating new exception types.

[Marc Prud'hommeaux]

Added NoResultException and NonUniqueResultException to kernel to allow the identification of the case where a unique result was selected by either none or too many were found