| /******************************************************************************* |
| * Copyright (c) 2005, 2008 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 |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| * |
| *******************************************************************************/ |
| package org.eclipse.jst.jsp.core.internal.taglib; |
| |
| |
| import org.eclipse.core.resources.IFile; |
| import org.eclipse.core.resources.IProject; |
| import org.eclipse.jdt.core.ElementChangedEvent; |
| import org.eclipse.jdt.core.IElementChangedListener; |
| import org.eclipse.jdt.core.IJavaElement; |
| import org.eclipse.jdt.core.IJavaElementDelta; |
| import org.eclipse.jdt.core.IJavaProject; |
| import org.eclipse.jdt.core.IType; |
| |
| /** |
| * Manages creation and caching (ordered MRU) of TaglibHelpers. |
| * Removes helpers when their classpath changes (so they are rebuilt). |
| * There is one helper per project (with a specific classpath entry). |
| * |
| * @author pavery |
| */ |
| public class TaglibHelperManager implements IElementChangedListener { |
| |
| |
| private static TaglibHelperManager instance = null; |
| // using a cache of just 3 loaders |
| private TaglibHelperCache fCache = new TaglibHelperCache(3); |
| |
| private TaglibHelperManager() { |
| // use instance |
| } |
| public static synchronized TaglibHelperManager getInstance() { |
| if(instance == null) |
| instance = new TaglibHelperManager(); |
| return instance; |
| } |
| |
| public TaglibHelper getTaglibHelper(IFile f) { |
| IProject p = f.getProject(); |
| return getHelperFromCache(p); |
| } |
| |
| /** |
| * @param projectPath |
| */ |
| private TaglibHelper getHelperFromCache(IProject project) { |
| return fCache.getHelper(project); |
| } |
| |
| /** |
| * Update classpath for appropriate loader. |
| * @see org.eclipse.jdt.core.IElementChangedListener#elementChanged(org.eclipse.jdt.core.ElementChangedEvent) |
| */ |
| public void elementChanged(ElementChangedEvent event) { |
| // handle classpath changes |
| IJavaElementDelta delta = event.getDelta(); |
| if (delta.getElement().getElementType() == IJavaElement.JAVA_MODEL) { |
| IJavaElementDelta[] changed = delta.getChangedChildren(); |
| for (int i = 0; i < changed.length; i++) { |
| if ((changed[i].getFlags() & IJavaElementDelta.F_CLASSPATH_CHANGED) != 0 || (changed[i].getFlags() & IJavaElementDelta.F_REORDER) != 0 || (changed[i].getFlags() & IJavaElementDelta.F_RESOLVED_CLASSPATH_CHANGED) != 0 || (changed[i].getFlags() & IJavaElementDelta.F_PRIMARY_RESOURCE) != 0) { |
| IJavaElement proj = changed[i].getElement(); |
| handleClasspathChange(changed, i, proj); |
| } |
| } |
| } |
| else if (delta.getElement().getElementType() == IJavaElement.COMPILATION_UNIT) { |
| IJavaElementDelta[] changed = delta.getChangedChildren(); |
| for (int i = 0; i < changed.length; i++) { |
| if ((changed[i].getFlags() & IJavaElementDelta.F_SUPER_TYPES) != 0) { |
| IJavaElement element = changed[i].getElement(); |
| handleSuperTypeChange(element); |
| } |
| } |
| } |
| } |
| |
| private void handleSuperTypeChange(IJavaElement element) { |
| IJavaProject project = element.getJavaProject(); |
| if (element instanceof IType) { |
| fCache.invalidate(project.getProject().getName(), ((IType) element).getFullyQualifiedName()); |
| } |
| } |
| |
| /** |
| * @param changed |
| * @param i |
| * @param proj |
| */ |
| private void handleClasspathChange(IJavaElementDelta[] changed, int i, IJavaElement proj) { |
| if (proj.getElementType() == IJavaElement.JAVA_PROJECT) { |
| String projectName = ((IJavaProject) proj).getProject().getName(); |
| fCache.removeHelper(projectName); |
| } |
| } |
| } |