/** @return */
 private EClassifier getKeyFieldTypeFromKeyClass() {
   if (isKey()) {
     JavaClass key = getCMPEntity().getPrimaryKey();
     if (key != null
         && key.getQualifiedName() != null
         && !key.getQualifiedName().startsWith("java.lang")) { // $NON-NLS-1$
       Field field = key.getFieldExtended(getName());
       if (field != null) return field.getEType();
     } else return key;
   }
   return null;
 }