title: IllegalArgumentException: argument type mismatch in Hibernate
body: <p>Out of the blue I started getting “IllegalArgumentException: argument type mismatch” in hibernate. The hibernate entity was working for quite some time and svn logs confirm the code to be intact.   </p>
  
  <p>What might be the case?<br>
  Here’s part of the exception </p>
  
  <pre><code>Jan 16, 2010 10:47:09 PM org.apache.catalina.core.StandardWrapperValve invoke
  SEVERE: Servlet.service() for servlet Faces Servlet threw exception
  java.lang.IllegalArgumentException: argument type mismatch
      at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
      at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
      at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
      at java.lang.reflect.Method.invoke(Method.java:597)
      at org.hibernate.property.BasicPropertyAccessor$BasicSetter.set(BasicPropertyAccessor.java:42)
      at org.hibernate.tuple.entity.AbstractEntityTuplizer.setPropertyValues(AbstractEntityTuplizer.java:337)
      at org.hibernate.tuple.entity.PojoEntityTuplizer.setPropertyValues(PojoEntityTuplizer.java:200)
      at org.hibernate.persister.entity.AbstractEntityPersister.setPropertyValues(AbstractEntityPersister.java:3566)
      at org.hibernate.engine.TwoPhaseLoad.initializeEntity(TwoPhaseLoad.java:129)
      at org.hibernate.loader.Loader.initializeEntitiesAndCollections(Loader.java:854)
      at org.hibernate.loader.Loader.doQuery(Loader.java:729)
      at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:236)
      at org.hibernate.loader.Loader.doList(Loader.java:2220)
      at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2104)
      at org.hibernate.loader.Loader.list(Loader.java:2099)
      at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:378)
      at org.hibernate.hql.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:338)
      at org.hibernate.engine.query.HQLQueryPlan.performList(HQLQueryPlan.java:172)
      at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1121)
      at org.hibernate.impl.QueryImpl.list(QueryImpl.java:79)
      at org.springframework.orm.hibernate3.HibernateTemplate$30.doInHibernate(HibernateTemplate.java:930)
      at org.springframework.orm.hibernate3.HibernateTemplate.doExecute(HibernateTemplate.java:419)
      at org.springframework.orm.hibernate3.HibernateTemplate.executeWithNativeSession(HibernateTemplate.java:374)
      at org.springframework.orm.hibernate3.HibernateTemplate.find(HibernateTemplate.java:921)
  </code></pre>