Hi, Created a JIRA for this: https://issues.apache.org/jira/browse/OPENJPA-1200
Regards, Ravi. Ravi P Palacherla wrote: > > Hi Mike, > > Please download the testcase from : > http://n2.nabble.com/file/n3306514/openJPATestCase.zip openJPATestCase.zip > > The following changes are needed : > build.xml ( point to proper "basedir" and "<path id="libs">" ) > persistence.xml ( jdbc configurations.) > > Regards, > Ravi. > > > > Michael Dick wrote: >> >> Hi Ravi, >> >> Could you upload the testcase you mentioned? This sounds like an >> interesting >> issue, not sure I have the full picture at the moment, but it might >> warrant >> a JIRA for further investigation. >> >> -mike >> >> On Wed, Jul 22, 2009 at 4:43 PM, rpalache >> <[email protected]>wrote: >> >>> >>> Hi , >>> >>> Here is the cause of the issue: >>> >>> getSelectSubclasses() of ValueMappingImpl.java is checking for criteria. >>> >>> "return (_criteria) ? Select.SUBS_JOINABLE >>> : Select.SUBS_ANY_JOINABLE;" >>> >>> If criteria is selected then "Select.SUBS_JOINABLE" is returned which >>> will >>> generate a select statement that has subclass criteria ( in my E.g: >>> t0.ITEM_TYPE = ? ) >>> >>> If criteria is not selected then "Select.SUBS_ANY_JOINABLE" is returned >>> which will not generate the above condition. >>> >>> So the question is if we have to make Select.SUBS_JOINABLE the default >>> behavior. >>> >>> I think throwing class cast exception is bad and hence the default >>> behavior >>> need to be changed to Select.SUBS_JOINABLE. >>> >>> Thanks in advance, >>> Ravi. >>> >>> >>> rpalache wrote: >>> > >>> > Hi All, >>> > >>> > I have an openJPA application with following entities: >>> > >>> > "Item" Entity with SINGLE_TABLE inheritance strategy. >>> > DiscriminatorColumn on this ITEM_TYPE. >>> > >>> > "Book" and "Movie" entities extend "Item." >>> > >>> > "Artist" entity has 1-many relationship with "Book." >>> > >>> > The following results in classcastexception : >>> > Artist artist = em.find(Artist.class, "Herman Hess"); >>> > List<Book> books= artist.getBooks(); >>> > >>> > "artist.getBooks()" results in rows that contain both "Book" >>> and"Movie" >>> > hence I get the following classcast : >>> > Exception in thread "main" java.lang.ClassCastException: >>> > org.apache.openjpa.enhance.model$Movie$pcsubclass >>> > >>> > When I add @ElementClassCriteria to the Artist to Book relationship >>> then >>> > that resolves the issue. >>> > @OneToMany(cascade=CascadeType.ALL, fetch=FetchType.EAGER, >>> > mappedBy="artist") >>> > @org.apache.openjpa.persistence.jdbc.ElementClassCriteria >>> > public List<Book> books; >>> > >>> > The reason for this issue is : >>> > without @ElementClassCriteria the SQL generated is : >>> > SELECT t0.UID1, t0.ITEM_TYPE, t0.title, t0.PAGE_COUNT FROM ITEM t0 >>> WHERE >>> > t0.ARTIST = ? >>> > [params=(String) Herman Hess] >>> > >>> > With @ElementClassCriteria the SQL generated is : >>> > SELECT t0.UID1, t0.ITEM_TYPE, t0.title, t0.PAGE_COUNT FROM ITEM t0 >>> WHERE >>> > t0.ARTIST = ? AND t0.ITEM_TYPE = ? >>> > [params=(String) Herman Hess, (String) BOOK] >>> > >>> > My questions regarding this is as follows: >>> > >>> > 1) @ElementClassCriteria is an openJPA specific annotation. Can I have >>> a >>> > JPA specific solution for this problem ? >>> > >>> > >>> > 2) If I have a very big application(s) and lots of relations with the >>> > above described behavior. >>> > Then do I have to add it to each and every entity class that has >>> the >>> > relationship ? >>> > Is there any property that I can define in the persistence.xml >>> rather >>> > than in entities ? >>> > >>> > I have a simple testcase demonstrating the issue. >>> > I can upload it if needed. >>> > >>> > Regards, >>> > Ravi. >>> > >>> > >>> >>> -- >>> View this message in context: >>> http://n2.nabble.com/ClasscastException-when-ClassCrietria-is-not-used.-tp3290568p3306077.html >>> Sent from the OpenJPA Developers mailing list archive at Nabble.com. >>> >> >> > > -- View this message in context: http://n2.nabble.com/ClasscastException-when-ClassCrietria-is-not-used.-tp3290568p3345152.html Sent from the OpenJPA Developers mailing list archive at Nabble.com.
