protected void checkForPrimaryKeys(final Object realObject) throws ClassNotPersistenceCapableException
    {
        // if no PKs are specified OJB can't handle this class !
        if (m_pkValues == null || m_pkValues.length == 0)
        {
            throw createException("OJB needs at least one primary key attribute for class: ", realObject, null);
        }
// arminw: should never happen
//        if(m_pkValues[0] instanceof ValueContainer)
//            throw new OJBRuntimeException("Can't handle pk values of type "+ValueContainer.class.getName());
    }
protected void checkForPrimaryKeys ( final Object realObject ) throws ClassNotPersistenceCapableException { if ( m_pkValues == null || m_pkValues . length == 0 ) { throw createException ( "OJB needs at least one primary key attribute for class: " , realObject , null ) ; } }
OJB can handle only classes that declare at least one primary key attribute,
this method checks this condition.

@param realObject The real object to check
@throws ClassNotPersistenceCapableException thrown if no primary key is specified for the objects class