From: lempinen <lempinen@ac1ea38d-2e2b-0410-8846-a27921b304fc>
Date: Tue, 12 Oct 2010 10:15:36 +0000 (+0000)
Subject: A better solution to prevent directly instantiating a module to itself
X-Git-Tag: simantics-1.2.1~29
X-Git-Url: https://gerrit.simantics.org/r/gitweb?a=commitdiff_plain;h=2bf3b2de5a37411cd66f4943596c0ff9a289d0f3;p=simantics%2Fsysdyn.git

A better solution to prevent directly instantiating a module to itself

git-svn-id: https://www.simantics.org/svn/simantics/sysdyn/trunk@18385 ac1ea38d-2e2b-0410-8846-a27921b304fc
---

diff --git a/org.simantics.sysdyn.ui/src/org/simantics/sysdyn/ui/editor/participant/SysdynPopulateElementDropParticipant.java b/org.simantics.sysdyn.ui/src/org/simantics/sysdyn/ui/editor/participant/SysdynPopulateElementDropParticipant.java
index 6c0cbf61..5c434c2c 100644
--- a/org.simantics.sysdyn.ui/src/org/simantics/sysdyn/ui/editor/participant/SysdynPopulateElementDropParticipant.java
+++ b/org.simantics.sysdyn.ui/src/org/simantics/sysdyn/ui/editor/participant/SysdynPopulateElementDropParticipant.java
@@ -1,25 +1,22 @@
 package org.simantics.sysdyn.ui.editor.participant;
 
-import java.awt.datatransfer.Transferable;
-import java.awt.datatransfer.UnsupportedFlavorException;
 import java.awt.dnd.DropTargetDragEvent;
-import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collection;
 
-import org.eclipse.core.runtime.IAdaptable;
-import org.eclipse.jface.viewers.IStructuredSelection;
 import org.simantics.db.ReadGraph;
 import org.simantics.db.Resource;
 import org.simantics.db.exception.DatabaseException;
 import org.simantics.db.request.Read;
 import org.simantics.diagram.adapter.GraphToDiagramSynchronizer;
 import org.simantics.diagram.ui.DiagramModelHints;
+import org.simantics.g2d.dnd.ElementClassDragItem;
 import org.simantics.g2d.dnd.IDnDContext;
+import org.simantics.g2d.element.handler.impl.StaticObjectAdapter;
 import org.simantics.modeling.ModelingResources;
 import org.simantics.modeling.ui.diagramEditor.PopulateElementDropParticipant;
 import org.simantics.structural.stubs.StructuralResource2;
 import org.simantics.sysdyn.SysdynResource;
-import org.simantics.ui.dnd.LocalObjectTransfer;
-import org.simantics.ui.dnd.LocalObjectTransferable;
 
 public class SysdynPopulateElementDropParticipant extends PopulateElementDropParticipant {
 
@@ -29,66 +26,46 @@ public class SysdynPopulateElementDropParticipant extends PopulateElementDropPar
 
     @Override
     public void dragEnter(DropTargetDragEvent dtde, IDnDContext dp) {
-        Transferable tr = dtde.getTransferable();
-        if (tr.isDataFlavorSupported(LocalObjectTransferable.FLAVOR)) {
-            // This must be done to have SWT transfer set the source data
-            Object obj = null;
-            try {
-                obj = tr.getTransferData(LocalObjectTransferable.FLAVOR);
-            } catch (UnsupportedFlavorException e) {
-                e.printStackTrace();
-            } catch (IOException e) {
-                e.printStackTrace();
-            }
-            
-            // Check SWT
-            if (!(obj instanceof IStructuredSelection)) {
-                obj = LocalObjectTransfer.getTransfer().getObject();
-            }
-            
-            if (obj instanceof IStructuredSelection) {
-                final IStructuredSelection sel = (IStructuredSelection) obj;
-                if (!sel.isEmpty()) {
-                	
-                	boolean allowed = true;
-                	try {
-                		allowed = synchronizer.getSession().syncRequest(new Read<Boolean>(){
+        super.dragEnter(dtde, dp);
+        
+        // Check that user is not trying to populate a module to itself. 
+        // This doesn't prevent infinite recursion if there is one module between two exactly the same modules.
+        // e.g. WorkModule -> WokrforceModule -> WorkModule creates an infinite recursion
+        final Collection<ElementClassDragItem> items = dp.getItemsByClass(ElementClassDragItem.class);
+        if(!items.isEmpty()) {
+        	 Collection<ElementClassDragItem> unvalidModules = null;
+        	try {
+        		unvalidModules = synchronizer.getSession().syncRequest(new Read<Collection<ElementClassDragItem>>() {
 
-							@Override
-							public Boolean perform(ReadGraph graph)
-									throws DatabaseException {
-			                    for (Object elm : sel.toList()) {
-			                        if (elm instanceof IAdaptable) {
-			                        	Object r = ((IAdaptable) elm).getAdapter(Resource.class);
-			                        	if(r != null && r instanceof Resource) {
-			                        		Resource resource = (Resource)r;
-			                        		SysdynResource sr = SysdynResource.getInstance(graph);
-			                        		if(graph.isInheritedFrom(resource, sr.ModuleSymbol)) {
-			                        			Resource module = graph.getSingleObject(resource, ModelingResources.getInstance(graph).SymbolToComponentType);
-			                        			Resource configuration = graph.getSingleObject(module, StructuralResource2.getInstance(graph).IsDefinedBy);
-			                        			Resource dia = graph.getSingleObject(configuration, ModelingResources.getInstance(graph).CompositeToDiagram);
-			                        			Resource editorDia = diagram.getHint(DiagramModelHints.KEY_DIAGRAM_RESOURCE);
-			                        			if(dia.equals(editorDia))
-			                        				return false;
-			                        		}
-			                        	}
-			                        }
-			                    }
-								return true;
-							}
-							
-						});
-					} catch (DatabaseException e) {
-						e.printStackTrace();
+					@Override
+					public Collection<ElementClassDragItem> perform(ReadGraph graph)
+							throws DatabaseException {
+						 Collection<ElementClassDragItem> unvalidModules = new ArrayList<ElementClassDragItem>();
+				        	for(ElementClassDragItem item : items) {
+				        		StaticObjectAdapter soa = item.getElementClass().getSingleItem(StaticObjectAdapter.class);
+				        		Resource type = soa.adapt(Resource.class);
+				        		
+                        		SysdynResource sr = SysdynResource.getInstance(graph);
+                        		if(graph.isInheritedFrom(type, sr.ModuleSymbol)) {
+                        			Resource module = graph.getSingleObject(type, ModelingResources.getInstance(graph).SymbolToComponentType);
+                        			Resource configuration = graph.getSingleObject(module, StructuralResource2.getInstance(graph).IsDefinedBy);
+                        			Resource dia = graph.getSingleObject(configuration, ModelingResources.getInstance(graph).CompositeToDiagram);
+                        			Resource editorDia = diagram.getHint(DiagramModelHints.KEY_DIAGRAM_RESOURCE);
+                        			if(dia.equals(editorDia))
+                        				unvalidModules.add(item);
+                        		}
+				        	}
+						return unvalidModules;
 					}
-					
-					// Trying to populate an instance of self to diagram -> infinite recursion
-					// This limitation should be removed by allowing differentation (copies) from modules. i.e. detaching from class and creating a new module type
-					if(!allowed)
-						return;
-                }
-            }
+				});
+			} catch (DatabaseException e) {
+				e.printStackTrace();
+			}
+			if(!unvalidModules.isEmpty()) {
+				for(ElementClassDragItem item : unvalidModules) {
+					dp.remove(item);
+				}
+			}
         }
-        super.dragEnter(dtde, dp);
     }
 }