Restrictions.eq In Criteria Not matching a property of type java.lang.Class --------------------------------------------------------------------------- Key: HHH-1369 URL: http://opensource.atlassian.com/projects/hibernate/browse/HHH-1369 Project: Hibernate3 Issue Type: Bug Components: query-criteria Affects Versions: 3.1 Environment: HB 3.1, Hibernate annotations 3.1-beta-7, Postgres 8.0.3 Reporter: Matt Todd Attachments: criteriaclass.zip When using criteria query to get an entity using the following method: session.createCriteria(Vocabulary.class).add(Restrictions.eq("klass", MethodOfContact.class)).uniqueResult() No results are returned. Using an alternative method: session.createCriteria(Vocabulary.class).add(Restrictions.in("klass", new Object[] {MethodOfContact.class})).uniqueResult() returns the correct result. The annotations on the mapped class are: @Column(unique=true, nullable = false) private Class klass; The error is possibly comming from here looking at the debug: 15:50:55,479 DEBUG SQL:346 - /* criteria query */ select this_.id as id1_1_, this_.default_value as default5_1_1_, this_.name as name1_1_, this_.klass as klass1_1_, this_.type as type1_1_, vocabulary2_.id as id0_0_, vocabulary2_.available as available0_0_, vocabulary2_.value as value0_0_, vocabulary2_.type as type0_0_ from vocabulary this_ left outer join vocabulary_value vocabulary2_ on this_.default_value=vocabulary2_.id where this_.klass=? Hibernate: /* criteria query */ select this_.id as id1_1_, this_.default_value as default5_1_1_, this_.name as name1_1_, this_.klass as klass1_1_, this_.type as type1_1_, vocabulary2_.id as id0_0_, vocabulary2_.available as available0_0_, vocabulary2_.value as value0_0_, vocabulary2_.type as type0_0_ from vocabulary this_ left outer join vocabulary_value vocabulary2_ on this_.default_value=vocabulary2_.id where this_.klass=? 15:50:55,481 DEBUG AbstractBatcher:424 - preparing statement 15:50:55,495 DEBUG GooGooStatementCache:381 - cxnStmtMgr.statementSet( org.postgresql.jdbc3.Jdbc3Connection@650892 ).size(): 1 15:50:55,500 DEBUG GooGooStatementCache:117 - checkoutStatement: com.mchange.v2.c3p0.stmt.GlobalMaxOnlyStatementCache stats -- total size: 1; checked out: 1; num connections: 1; num keys: 1 15:50:55,511 DEBUG StringType:79 - binding ''uk.co.iizuka.advice.MethodOfContact'' to parameter: 1 The last debug line seems a possibility for the error as the binding classname has double quotes around it. When using the "Restrictions.in" method, there are only single quotes.