I have a database table with 5 rows.
The first time I do a select all I get a StackOverflowError
em.createQuery("SELECT e FROM " + clazz.getSimpleName() + " e");
How ever if I do a single select on each of the rows
em.find(clazz, 1);
em.find(clazz, 2);
em.find(clazz, 3);
em.find(clazz, 4);
em.find(clazz, 5);
Then the select all works perfectly. I'm guessing this is something to do with the records not being in a cache yet?
Full stack trace is too long here is the top
java.lang.StackOverflowError at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.loadClass(DefaultClassLoader.java:107) at java.lang.ClassLoader.loadClass(Unknown Source) at java.lang.ClassLoader.loadClassInternal(Unknown Source) at com.mysql.jdbc.Util.handleNewInstance(Util.java:427) at com.mysql.jdbc.PreparedStatement.getInstance(PreparedStatement.java:872) at com.mysql.jdbc.ConnectionImpl.clientPrepareStatement(ConnectionImpl.java:1498) at com.mysql.jdbc.ConnectionImpl.prepareStatement(ConnectionImpl.java:4270) at com.mysql.jdbc.ConnectionImpl.prepareStatement(ConnectionImpl.java:4169) at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.prepareStatement(DatabaseAccessor.java:1401) at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.prepareStatement(DatabaseAccessor.java:1350) at org.eclipse.persistence.internal.databaseaccess.DatabaseCall.prepareStatement(DatabaseCall.java:652) at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.basicExecuteCall(DatabaseAccessor.java:576) at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.executeCall(DatabaseAccessor.java:526) at org.eclipse.persistence.sessions.server.ServerSession.executeCall(ServerSession.java:529) at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.executeCall(DatasourceCallQueryMechanism.java:206) at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.executeCall(DatasourceCallQueryMechanism.java:192) at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.selectOneRow(DatasourceCallQueryMechanism.java:664) at org.eclipse.persistence.internal.queries.ExpressionQueryMechanism.selectOneRowFromTable(ExpressionQueryMechanism.java:2582) at org.eclipse.persistence.internal.queries.ExpressionQueryMechanism.selectOneRow(ExpressionQueryMechanism.java:2553) at org.eclipse.persistence.queries.ReadObjectQuery.executeObjectLevelReadQuery(ReadObjectQuery.java:439) at org.eclipse.persistence.queries.ObjectLevelReadQuery.executeDatabaseQuery(ObjectLevelReadQuery.java:1076) at org.eclipse.persistence.queries.DatabaseQuery.execute(DatabaseQuery.java:740) at org.eclipse.persistence.queries.ObjectLevelReadQuery.execute(ObjectLevelReadQuery.java:1036) at org.eclipse.persistence.queries.ReadObjectQuery.execute(ReadObjectQuery.java:407) at org.eclipse.persistence.internal.sessions.AbstractSession.internalExecuteQuery(AbstractSession.java:2392) at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1291) at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1273) at org.eclipse.persistence.internal.indirection.NoIndirectionPolicy.valueFromQuery(NoIndirectionPolicy.java:309) at org.eclipse.persistence.mappings.ForeignReferenceMapping.valueFromRowInternal(ForeignReferenceMapping.java:1850) at org.eclipse.persistence.mappings.OneToOneMapping.valueFromRowInternal(OneToOneMapping.java:1623) at org.eclipse.persistence.mappings.ForeignReferenceMapping.valueFromRow(ForeignReferenceMapping.java:1739) at org.eclipse.persistence.mappings.DatabaseMapping.readFromRowIntoObject(DatabaseMapping.java:1283) at org.eclipse.persistence.internal.descriptors.ObjectBuilder.buildAttributesIntoObject(ObjectBuilder.java:342) at org.eclipse.persistence.internal.descriptors.ObjectBuilder.buildObject(ObjectBuilder.java:717) at org.eclipse.persistence.internal.descriptors.ObjectBuilder.buildObject(ObjectBuilder.java:504) at org.eclipse.persistence.internal.descriptors.ObjectBuilder.buildObject(ObjectBuilder.java:454) at org.eclipse.persistence.queries.ObjectLevelReadQuery.buildObject(ObjectLevelReadQuery.java:723) at org.eclipse.persistence.queries.ReadObjectQuery.executeObjectLevelReadQuery(ReadObjectQuery.java:448) at org.eclipse.persistence.queries.ObjectLevelReadQuery.executeDatabaseQuery(ObjectLevelReadQuery.java:1076) at org.eclipse.persistence.queries.DatabaseQuery.execute(DatabaseQuery.java:740) at org.eclipse.persistence.queries.ObjectLevelReadQuery.execute(ObjectLevelReadQuery.java:1036) at org.eclipse.persistence.queries.ReadObjectQuery.execute(ReadObjectQuery.java:407) at org.eclipse.persistence.internal.sessions.AbstractSession.internalExecuteQuery(AbstractSession.java:2392) at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1291) at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1273) at org.eclipse.persistence.internal.indirection.NoIndirectionPolicy.valueFromQuery(NoIndirectionPolicy.java:309) at org.eclipse.persistence.mappings.ForeignReferenceMapping.valueFromRowInternal(ForeignReferenceMapping.java:1850) at org.eclipse.persistence.mappings.OneToOneMapping.valueFromRowInternal(OneToOneMapping.java:1623) at org.eclipse.persistence.mappings.ForeignReferenceMapping.valueFromRow(ForeignReferenceMapping.java:1739) at org.eclipse.persistence.mappings.DatabaseMapping.readFromRowIntoObject(DatabaseMapping.java:1283) at org.eclipse.persistence.internal.descriptors.ObjectBuilder.buildAttributesIntoObject(ObjectBuilder.java:342) at org.eclipse.persistence.internal.descriptors.ObjectBuilder.buildObject(ObjectBuilder.java:717) at org.eclipse.persistence.internal.descriptors.ObjectBuilder.buildObject(ObjectBuilder.java:504) at org.eclipse.persistence.internal.descriptors.ObjectBuilder.buildObject(ObjectBuilder.java:454) at org.eclipse.persistence.queries.ObjectLevelReadQuery.buildObject(ObjectLevelReadQuery.java:723) at org.eclipse.persistence.queries.ReadObjectQuery.executeObjectLevelReadQuery(ReadObjectQuery.java:448) at org.eclipse.persistence.queries.ObjectLevelReadQuery.executeDatabaseQuery(ObjectLevelReadQuery.java:1076) at org.eclipse.persistence.queries.DatabaseQuery.execute(DatabaseQuery.java:740) at org.eclipse.persistence.queries.ObjectLevelReadQuery.execute(ObjectLevelReadQuery.java:1036) at org.eclipse.persistence.queries.ReadObjectQuery.execute(ReadObjectQuery.java:407) at org.eclipse.persistence.internal.sessions.AbstractSession.internalExecuteQuery(AbstractSession.java:2392) at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1291) at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1273) at org.eclipse.persistence.internal.indirection.NoIndirectionPolicy.valueFromQuery(NoIndirectionPolicy.java:309) at org.eclipse.persistence.mappings.ForeignReferenceMapping.valueFromRowInternal(ForeignReferenceMapping.java:1850) at org.eclipse.persistence.mappings.OneToOneMapping.valueFromRowInternal(OneToOneMapping.java:1623) at org.eclipse.persistence.mappings.ForeignReferenceMapping.valueFromRow(ForeignReferenceMapping.java:1739) at org.eclipse.persistence.mappings.DatabaseMapping.readFromRowIntoObject(DatabaseMapping.java:1283) at org.eclipse.persistence.internal.descriptors.ObjectBuilder.buildAttributesIntoObject(ObjectBuilder.java:342) at org.eclipse.persistence.internal.descriptors.ObjectBuilder.buildObject(ObjectBuilder.java:717) at org.eclipse.persistence.internal.descriptors.ObjectBuilder.buildObject(ObjectBuilder.java:504) at org.eclipse.persistence.internal.descriptors.ObjectBuilder.buildObject(ObjectBuilder.java:454) at org.eclipse.persistence.queries.ObjectLevelReadQuery.buildObject(ObjectLevelReadQuery.java:723) at org.eclipse.persistence.queries.ReadObjectQuery.executeObjectLevelReadQuery(ReadObjectQuery.java:448) at org.eclipse.persistence.queries.ObjectLevelReadQuery.executeDatabaseQuery(ObjectLevelReadQuery.java:1076) at org.eclipse.persistence.queries.DatabaseQuery.execute(DatabaseQuery.java:740) at org.eclipse.persistence.queries.ObjectLevelReadQuery.execute(ObjectLevelReadQuery.java:1036) at org.eclipse.persistence.queries.ReadObjectQuery.execute(ReadObjectQuery.java:407) at org.eclipse.persistence.internal.sessions.AbstractSession.internalExecuteQuery(AbstractSession.java:2392) at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1291) at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1273) at org.eclipse.persistence.internal.indirection.NoIndirectionPolicy.valueFromQuery(NoIndirectionPolicy.java:309) at org.eclipse.persistence.mappings.ForeignReferenceMapping.valueFromRowInternal(ForeignReferenceMapping.java:1850) at org.eclipse.persistence.mappings.OneToOneMapping.valueFromRowInternal(OneToOneMapping.java:1623) at org.eclipse.persistence.mappings.ForeignReferenceMapping.valueFromRow(ForeignReferenceMapping.java:1739) at org.eclipse.persistence.mappings.DatabaseMapping.readFromRowIntoObject(DatabaseMapping.java:1283) at org.eclipse.persistence.internal.descriptors.ObjectBuilder.buildAttributesIntoObject(ObjectBuilder.java:342) at org.eclipse.persistence.internal.descriptors.ObjectBuilder.buildObject(ObjectBuilder.java:717) at org.eclipse.persistence.internal.descriptors.ObjectBuilder.buildObject(ObjectBuilder.java:504) at org.eclipse.persistence.internal.descriptors.ObjectBuilder.buildObject(ObjectBuilder.java:454) at org.eclipse.persistence.queries.ObjectLevelReadQuery.buildObject(ObjectLevelReadQuery.java:723) at org.eclipse.persistence.queries.ReadObjectQuery.executeObjectLevelReadQuery(ReadObjectQuery.java:448) at org.eclipse.persistence.queries.ObjectLevelReadQuery.executeDatabaseQuery(ObjectLevelReadQuery.java:1076) at org.eclipse.persistence.queries.DatabaseQuery.execute(DatabaseQuery.java:740)
I assume you have set your cache-type to NONE and have a relationship cycle that does not use LAZY.
Do not set your cache-type to NONE, this is not how you disable the shared cache. cache-type of NONE if for only very special cases.
To disable the shared cache use,
<property name="eclipselink.cache.shared.default" value="false"/>
See, http://wiki.eclipse.org/EclipseLink/FAQ/How_to_disable_the_shared_cache%3F