I'm currently trying to implement a ManyToMany Relationship with Data in the JoinTable. I'm following this approach with the Eclipselink JPA Framework. But I'm getting the following exception:
org.eclipse.persistence.exceptions.EntityManagerSetupException.predeployFailed(EntityManagerSetupException.java:210) ... 23 more Caused by: Exception [EclipseLink-7298] (Eclipse Persistence Services - 2.1.1.v20100817-r8050): org.eclipse.persistence.exceptions.ValidationException Exception Description: The mapping [group] from the embedded ID class [class de.kapieren.mbm.server.model.UserGroupPK] is an invalid mapping for this class. An embeddable class that is used with an embedded ID specification (attribute [pk] from the source [class de.kapieren.mbm.server.model.GroupMembership]) can only contain basic mappings. Either remove the non basic mapping or change the embedded ID specification on the source to be embedded
Does anybody know whats the meaning of basic mappings in relationship to embeddedId? What could be wrong here?