content: package oscfg.diagram.edit.policies;
  
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.HashSet;
  import java.util.Iterator;
  import java.util.LinkedList;
  import java.util.List;
  import java.util.Set;
  
  import org.eclipse.core.runtime.IAdaptable;
  import org.eclipse.emf.ecore.EObject;
  import org.eclipse.emf.ecore.EStructuralFeature;
  import org.eclipse.gef.EditPart;
  import org.eclipse.gef.commands.Command;
  import org.eclipse.gmf.runtime.diagram.core.util.ViewUtil;
  import org.eclipse.gmf.runtime.diagram.ui.commands.DeferredLayoutCommand;
  import org.eclipse.gmf.runtime.diagram.ui.commands.ICommandProxy;
  import org.eclipse.gmf.runtime.diagram.ui.commands.SetViewMutabilityCommand;
  import org.eclipse.gmf.runtime.diagram.ui.editpolicies.CanonicalEditPolicy;
  import org.eclipse.gmf.runtime.diagram.ui.requests.CreateViewRequest;
  import org.eclipse.gmf.runtime.emf.core.util.EObjectAdapter;
  import org.eclipse.gmf.runtime.notation.Node;
  import org.eclipse.gmf.runtime.notation.View;
  
  import oscfg.OscfgPackage;
  import oscfg.diagram.edit.parts.SWTimerEditPart;
  import oscfg.diagram.part.OscfgDiagramUpdater;
  import oscfg.diagram.part.OscfgNodeDescriptor;
  import oscfg.diagram.part.OscfgVisualIDRegistry;
  
  /**
   * @generated
   */
  public class HWCounterSoftwareTimersCanonicalEditPolicy extends
  		CanonicalEditPolicy {
  
  	/**
  	 * @generated
  	 */
  	protected void refreshOnActivate() {
  		// Need to activate editpart children before invoking the canonical refresh for EditParts to add event listeners
  		List<?> c = getHost().getChildren();
  		for (int i = 0; i < c.size(); i++) {
  			((EditPart) c.get(i)).activate();
  		}
  		super.refreshOnActivate();
  	}
  
  	/**
  	 * @generated
  	 */
  	protected EStructuralFeature getFeatureToSynchronize() {
  		return OscfgPackage.eINSTANCE.getHWCounter_SWTimers();
  	}
  
  	/**
  	 * @generated
  	 */
  	@SuppressWarnings("rawtypes")
  	protected List getSemanticChildrenList() {
  		View viewObject = (View) getHost().getModel();
  		LinkedList<EObject> result = new LinkedList<EObject>();
  		List<OscfgNodeDescriptor> childDescriptors = OscfgDiagramUpdater
  				.getHWCounterSoftwareTimers_7004SemanticChildren(viewObject);
  		for (OscfgNodeDescriptor d : childDescriptors) {
  			result.add(d.getModelElement());
  		}
  		return result;
  	}
  
  	/**
  	 * @generated
  	 */
  	protected boolean isOrphaned(Collection<EObject> semanticChildren,
  			final View view) {
  		return isMyDiagramElement(view)
  				&& !semanticChildren.contains(view.getElement());
  	}
  
  	/**
  	 * @generated
  	 */
  	private boolean isMyDiagramElement(View view) {
  		return SWTimerEditPart.VISUAL_ID == OscfgVisualIDRegistry
  				.getVisualID(view);
  	}
  
  	/**
  	 * @generated
  	 */
  	protected void refreshSemantic() {
  		if (resolveSemanticElement() == null) {
  			return;
  		}
  		LinkedList<IAdaptable> createdViews = new LinkedList<IAdaptable>();
  		List<OscfgNodeDescriptor> childDescriptors = OscfgDiagramUpdater
  				.getHWCounterSoftwareTimers_7004SemanticChildren((View) getHost()
  						.getModel());
  		LinkedList<View> orphaned = new LinkedList<View>();
  		// we care to check only views we recognize as ours
  		LinkedList<View> knownViewChildren = new LinkedList<View>();
  		for (View v : getViewChildren()) {
  			if (isMyDiagramElement(v)) {
  				knownViewChildren.add(v);
  			}
  		}
  		// alternative to #cleanCanonicalSemanticChildren(getViewChildren(), semanticChildren)
  		//
  		// iteration happens over list of desired semantic elements, trying to find best matching View, while original CEP
  		// iterates views, potentially losing view (size/bounds) information - i.e. if there are few views to reference same EObject, only last one 
  		// to answer isOrphaned == true will be used for the domain element representation, see #cleanCanonicalSemanticChildren()
  		for (Iterator<OscfgNodeDescriptor> descriptorsIterator = childDescriptors
  				.iterator(); descriptorsIterator.hasNext();) {
  			OscfgNodeDescriptor next = descriptorsIterator.next();
  			String hint = OscfgVisualIDRegistry.getType(next.getVisualID());
  			LinkedList<View> perfectMatch = new LinkedList<View>(); // both semanticElement and hint match that of NodeDescriptor
  			for (View childView : getViewChildren()) {
  				EObject semanticElement = childView.getElement();
  				if (next.getModelElement().equals(semanticElement)) {
  					if (hint.equals(childView.getType())) {
  						perfectMatch.add(childView);
  						// actually, can stop iteration over view children here, but
  						// may want to use not the first view but last one as a 'real' match (the way original CEP does
  						// with its trick with viewToSemanticMap inside #cleanCanonicalSemanticChildren
  					}
  				}
  			}
  			if (perfectMatch.size() > 0) {
  				descriptorsIterator.remove(); // precise match found no need to create anything for the NodeDescriptor
  				// use only one view (first or last?), keep rest as orphaned for further consideration
  				knownViewChildren.remove(perfectMatch.getFirst());
  			}
  		}
  		// those left in knownViewChildren are subject to removal - they are our diagram elements we didn't find match to,
  		// or those we have potential matches to, and thus need to be recreated, preserving size/location information.
  		orphaned.addAll(knownViewChildren);
  		//
  		ArrayList<CreateViewRequest.ViewDescriptor> viewDescriptors = new ArrayList<CreateViewRequest.ViewDescriptor>(
  				childDescriptors.size());
  		for (OscfgNodeDescriptor next : childDescriptors) {
  			String hint = OscfgVisualIDRegistry.getType(next.getVisualID());
  			IAdaptable elementAdapter = new CanonicalElementAdapter(
  					next.getModelElement(), hint);
  			CreateViewRequest.ViewDescriptor descriptor = new CreateViewRequest.ViewDescriptor(
  					elementAdapter, Node.class, hint, ViewUtil.APPEND, false,
  					host().getDiagramPreferencesHint());
  			viewDescriptors.add(descriptor);
  		}
  
  		boolean changed = deleteViews(orphaned.iterator());
  		//
  		CreateViewRequest request = getCreateViewRequest(viewDescriptors);
  		Command cmd = getCreateViewCommand(request);
  		if (cmd != null && cmd.canExecute()) {
  			SetViewMutabilityCommand.makeMutable(
  					new EObjectAdapter(host().getNotationView())).execute();
  			executeCommand(cmd);
  			@SuppressWarnings("unchecked")
  			List<IAdaptable> nl = (List<IAdaptable>) request.getNewObject();
  			createdViews.addAll(nl);
  		}
  		if (changed || createdViews.size() > 0) {
  			postProcessRefreshSemantic(createdViews);
  		}
  		if (createdViews.size() > 1) {
  			// perform a layout of the container
  			DeferredLayoutCommand layoutCmd = new DeferredLayoutCommand(host()
  					.getEditingDomain(), createdViews, host());
  			executeCommand(new ICommandProxy(layoutCmd));
  		}
  
  		makeViewsImmutable(createdViews);
  	}
  
  }
  