Prevent possibility of assining representation more than one level down. Closes #1660

Author: iTerminate

src/java/CdbWebPortal/src/java/gov/anl/aps/cdb/portal/controllers/ItemDomainMachineDesignBaseController.java

@@ -3475,8 +3475,14 @@ public void prepareMachineAssignRepresentingAssemblyElement() {
         }
 
         if (parentMachineDesign != null) {
+            ItemElement representsCatalogElement = parentMachineDesign.getRepresentsCatalogElement();
+            if (representsCatalogElement != null) {
+                SessionUtility.addErrorMessage("Represented Parent", "Parent item is represented by another assembly part, cannot link another level of representation.");
+                return;
+            }
+            
             Item assignedItem = parentMachineDesign.getAssignedItem();
-
+                        
             if (assignedItem != null && assignedItem.getItemElementDisplayList().size() != 0) {
                 elementsAvaiableForNodeRepresentation = controllerUtility.fetchElementsAvaiableForNodeRepresentation(current);
             } else {

src/java/CdbWebPortal/src/java/gov/anl/aps/cdb/portal/controllers/utilities/ItemDomainMachineDesignBaseControllerUtility.java

@@ -729,6 +729,14 @@ private void updateRepresentingAssemblyElementForMachine(ItemDomainMachineDesign
                 throw new InvalidObjectState(errMessage);
             }
         }
+        
+        ItemDomainMachineDesign parentMachineDesign = node.getParentMachineDesign();
+        if (representedElement != null && parentMachineDesign.getRepresentsCatalogElement() != null) {
+            String errMessage = node.getName();
+            errMessage += " has a parent " + parentMachineDesign.getName();
+            errMessage += " with represented element reference.";
+            throw new InvalidObjectState(errMessage);
+        }
 
         List<ItemElement> elements = fetchElementsAvaiableForNodeRepresentation(node);