| /******************************************************************************* |
| * Copyright (c) 2000, 2016 IBM Corporation and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| *******************************************************************************/ |
| package org.eclipse.dltk.ui.viewsupport; |
| |
| import java.util.ArrayList; |
| import java.util.HashMap; |
| import java.util.List; |
| import java.util.Stack; |
| |
| import org.eclipse.core.resources.IResource; |
| import org.eclipse.core.runtime.IAdaptable; |
| import org.eclipse.dltk.core.IModelElement; |
| import org.eclipse.dltk.core.ISourceModule; |
| import org.eclipse.swt.widgets.Item; |
| import org.eclipse.swt.widgets.Widget; |
| |
| |
| /** |
| * Helper class for updating error markers and other decorators that work on resources. |
| * Items are mapped to their element's underlying resource. |
| * Method <code>resourceChanged</code> updates all items that are affected from the changed |
| * elements. |
| */ |
| public class ResourceToItemsMapper { |
| |
| public static interface IContentViewerAccessor { |
| public void doUpdateItem(Widget item); |
| } |
| |
| |
| private static final int NUMBER_LIST_REUSE= 10; |
| |
| // map from resource to item |
| private HashMap fResourceToItem; |
| private Stack fReuseLists; |
| |
| private IContentViewerAccessor fContentViewerAccess; |
| |
| public ResourceToItemsMapper(IContentViewerAccessor viewer) { |
| fResourceToItem= new HashMap(); |
| fReuseLists= new Stack(); |
| |
| fContentViewerAccess= viewer; |
| } |
| |
| /** |
| * Must be called from the UI thread. |
| * @param changedResource Changed resource |
| */ |
| public void resourceChanged(IResource changedResource) { |
| Object obj= fResourceToItem.get(changedResource); |
| if (obj == null) { |
| // not mapped |
| } else if (obj instanceof Item) { |
| updateItem((Item) obj); |
| } else { // List of Items |
| List list= (List) obj; |
| for (int k= 0; k < list.size(); k++) { |
| updateItem((Item) list.get(k)); |
| } |
| } |
| } |
| |
| private void updateItem(Item item) { |
| if (!item.isDisposed()) { |
| fContentViewerAccess.doUpdateItem(item); |
| } |
| } |
| |
| /** |
| * Adds a new item to the map. |
| * @param element Element to map |
| * @param item The item used for the element |
| */ |
| public void addToMap(Object element, Item item) { |
| IResource resource= getCorrespondingResource(element); |
| if (resource != null) { |
| Object existingMapping= fResourceToItem.get(resource); |
| if (existingMapping == null) { |
| fResourceToItem.put(resource, item); |
| } else if (existingMapping instanceof Item) { |
| if (existingMapping != item) { |
| List list= getNewList(); |
| list.add(existingMapping); |
| list.add(item); |
| fResourceToItem.put(resource, list); |
| } |
| } else { // List |
| List list= (List) existingMapping; |
| if (!list.contains(item)) { |
| list.add(item); |
| } |
| } |
| } |
| } |
| |
| /** |
| * Removes an element from the map. |
| * @param element The data element |
| * @param item The table or tree item |
| */ |
| public void removeFromMap(Object element, Item item) { |
| IResource resource= getCorrespondingResource(element); |
| if (resource != null) { |
| Object existingMapping= fResourceToItem.get(resource); |
| if (existingMapping == null) { |
| return; |
| } else if (existingMapping instanceof Item) { |
| fResourceToItem.remove(resource); |
| } else { // List |
| List list= (List) existingMapping; |
| list.remove(item); |
| if (list.isEmpty()) { |
| fResourceToItem.remove(list); |
| releaseList(list); |
| } |
| } |
| } |
| } |
| |
| private List getNewList() { |
| if (!fReuseLists.isEmpty()) { |
| return (List) fReuseLists.pop(); |
| } |
| return new ArrayList(2); |
| } |
| |
| private void releaseList(List list) { |
| if (fReuseLists.size() < NUMBER_LIST_REUSE) { |
| fReuseLists.push(list); |
| } |
| } |
| |
| /** |
| * Clears the map. |
| */ |
| public void clearMap() { |
| fResourceToItem.clear(); |
| } |
| |
| /** |
| * Tests if the map is empty |
| * @return Returns if there are mappings |
| */ |
| public boolean isEmpty() { |
| return fResourceToItem.isEmpty(); |
| } |
| |
| private static IResource getCorrespondingResource(IModelElement elem) { |
| IResource res = elem.getResource(); |
| if (res == null) { |
| ISourceModule cu = (ISourceModule) elem |
| .getAncestor(IModelElement.SOURCE_MODULE); |
| if (cu != null) { |
| // elements in compilation units are mapped to the underlying |
| // resource of the original cu |
| res = cu.getResource(); |
| } |
| } |
| return res; |
| } |
| |
| /** |
| * Method that decides which elements can have error markers |
| * Returns null if an element can not have error markers. |
| * @param element The input element |
| * @return Returns the corresponding resource or null |
| */ |
| private static IResource getCorrespondingResource(Object element) { |
| if (element instanceof IModelElement) { |
| return getCorrespondingResource((IModelElement) element); |
| } else if (element instanceof IResource) { |
| return (IResource) element; |
| } else if (element instanceof IAdaptable) { |
| IResource res; |
| IModelElement elem = ((IAdaptable) element) |
| .getAdapter(IModelElement.class); |
| if (elem != null) { |
| return getCorrespondingResource(elem); |
| } else { |
| res = (((IAdaptable) element) |
| .getAdapter(IResource.class)); |
| } |
| return res; |
| } |
| return null; |
| } |
| |
| } |