| /******************************************************************************* |
| * Copyright (c) 2007, 2011 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.jdt.internal.ui.text.java; |
| |
| import org.eclipse.core.runtime.Assert; |
| |
| import org.eclipse.jface.text.templates.ContextTypeRegistry; |
| import org.eclipse.jface.text.templates.TemplateContextType; |
| |
| import org.eclipse.jdt.core.CompletionContext; |
| import org.eclipse.jdt.core.ElementChangedEvent; |
| import org.eclipse.jdt.core.ICompilationUnit; |
| import org.eclipse.jdt.core.IElementChangedListener; |
| import org.eclipse.jdt.core.IJavaElementDelta; |
| import org.eclipse.jdt.core.IJavaProject; |
| import org.eclipse.jdt.core.IType; |
| import org.eclipse.jdt.core.JavaCore; |
| import org.eclipse.jdt.core.JavaModelException; |
| |
| import org.eclipse.jdt.internal.corext.template.java.SWTContextType; |
| |
| import org.eclipse.jdt.ui.text.java.JavaContentAssistInvocationContext; |
| |
| import org.eclipse.jdt.internal.ui.JavaPlugin; |
| import org.eclipse.jdt.internal.ui.text.template.contentassist.TemplateEngine; |
| |
| |
| /** |
| * Computer that computes the template proposals for the SWT context type. |
| * |
| * @since 3.4 |
| */ |
| public class SWTTemplateCompletionProposalComputer extends AbstractTemplateCompletionProposalComputer { |
| |
| /** |
| * The name of <code>org.eclipse.swt.SWT</code> used to detect |
| * if a project uses SWT. |
| */ |
| private static final String SWT_TYPE_NAME= "org.eclipse.swt.SWT"; //$NON-NLS-1$ |
| |
| |
| /** |
| * Listener that resets the cached java project if its build path changes. |
| */ |
| private final class BuildPathChangeListener implements IElementChangedListener { |
| |
| @Override |
| public void elementChanged(ElementChangedEvent event) { |
| IJavaProject javaProject= getCachedJavaProject(); |
| if (javaProject == null) |
| return; |
| |
| IJavaElementDelta[] children= event.getDelta().getChangedChildren(); |
| for (int i= 0; i < children.length; i++) { |
| IJavaElementDelta child= children[i]; |
| if (javaProject.equals(child.getElement())) { |
| if (isClasspathChange(child)) { |
| setCachedJavaProject(null); |
| } |
| } |
| } |
| } |
| |
| /** |
| * Does the delta indicate a classpath change? |
| * @param delta the delta to inspect |
| * @return true if classpath has changed |
| */ |
| private boolean isClasspathChange(IJavaElementDelta delta) { |
| int flags= delta.getFlags(); |
| if (isClasspathChangeFlag(flags)) |
| return true; |
| |
| if ((flags & IJavaElementDelta.F_CHILDREN) != 0) { |
| IJavaElementDelta[] children= delta.getAffectedChildren(); |
| for (int i= 0; i < children.length; i++) { |
| if (isClasspathChangeFlag(children[i].getFlags())) |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| |
| /** |
| * Do the flags indicate a classpath change? |
| * @param flags the flags to inspect |
| * @return true if the flag flags a classpath change |
| */ |
| private boolean isClasspathChangeFlag(int flags) { |
| if ((flags & IJavaElementDelta.F_RESOLVED_CLASSPATH_CHANGED) != 0) |
| return true; |
| |
| if ((flags & IJavaElementDelta.F_ADDED_TO_CLASSPATH) != 0) |
| return true; |
| |
| if ((flags & IJavaElementDelta.F_REMOVED_FROM_CLASSPATH) != 0) |
| return true; |
| |
| if ((flags & IJavaElementDelta.F_ARCHIVE_CONTENT_CHANGED) != 0) |
| return true; |
| |
| return false; |
| } |
| } |
| |
| |
| /** |
| * Engine used to compute the proposals for this computer |
| */ |
| private final TemplateEngine fSWTTemplateEngine; |
| private final TemplateEngine fSWTMembersTemplateEngine; |
| private final TemplateEngine fSWTStatementsTemplateEngine; |
| |
| /** |
| * The Java project of the compilation unit for which a template |
| * engine has been computed last time if any |
| */ |
| private IJavaProject fCachedJavaProject; |
| /** |
| * Is org.eclipse.swt.SWT on class path of <code>fJavaProject</code>. Invalid |
| * if <code>fJavaProject</code> is <code>false</code>. |
| */ |
| private boolean fIsSWTOnClasspath; |
| |
| public SWTTemplateCompletionProposalComputer() { |
| ContextTypeRegistry templateContextRegistry= JavaPlugin.getDefault().getTemplateContextRegistry(); |
| fSWTTemplateEngine= createTemplateEngine(templateContextRegistry, SWTContextType.ID_ALL); |
| fSWTMembersTemplateEngine= createTemplateEngine(templateContextRegistry, SWTContextType.ID_MEMBERS); |
| fSWTStatementsTemplateEngine= createTemplateEngine(templateContextRegistry, SWTContextType.ID_STATEMENTS); |
| |
| JavaCore.addElementChangedListener(new BuildPathChangeListener()); |
| } |
| |
| private static TemplateEngine createTemplateEngine(ContextTypeRegistry templateContextRegistry, String contextTypeId) { |
| TemplateContextType contextType= templateContextRegistry.getContextType(contextTypeId); |
| Assert.isNotNull(contextType); |
| return new TemplateEngine(contextType); |
| } |
| |
| @Override |
| protected TemplateEngine computeCompletionEngine(JavaContentAssistInvocationContext context) { |
| ICompilationUnit unit= context.getCompilationUnit(); |
| if (unit == null) |
| return null; |
| |
| IJavaProject javaProject= unit.getJavaProject(); |
| if (javaProject == null) |
| return null; |
| |
| if (isSWTOnClasspath(javaProject)) { |
| CompletionContext coreContext= context.getCoreContext(); |
| if (coreContext != null) { |
| int tokenLocation= coreContext.getTokenLocation(); |
| if ((tokenLocation & CompletionContext.TL_MEMBER_START) != 0) { |
| return fSWTMembersTemplateEngine; |
| } |
| if ((tokenLocation & CompletionContext.TL_STATEMENT_START) != 0) { |
| return fSWTStatementsTemplateEngine; |
| } |
| } |
| return fSWTTemplateEngine; |
| } |
| |
| return null; |
| } |
| |
| /** |
| * Tells whether SWT is on the given project's class path. |
| * |
| * @param javaProject the Java project |
| * @return <code>true</code> if the given project's class path |
| */ |
| private synchronized boolean isSWTOnClasspath(IJavaProject javaProject) { |
| if (!javaProject.equals(fCachedJavaProject)) { |
| fCachedJavaProject= javaProject; |
| try { |
| IType type= javaProject.findType(SWT_TYPE_NAME); |
| fIsSWTOnClasspath= type != null; |
| } catch (JavaModelException e) { |
| fIsSWTOnClasspath= false; |
| } |
| } |
| return fIsSWTOnClasspath; |
| } |
| |
| /** |
| * Returns the cached Java project. |
| * |
| * @return the cached Java project or <code>null</code> if none |
| */ |
| private synchronized IJavaProject getCachedJavaProject() { |
| return fCachedJavaProject; |
| } |
| |
| /** |
| * Set the cached Java project. |
| * |
| * @param project or <code>null</code> to reset the cache |
| */ |
| private synchronized void setCachedJavaProject(IJavaProject project) { |
| fCachedJavaProject= project; |
| } |
| |
| } |