| /****************************************************************************** |
| * Copyright (c) 2002, 2003 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.gmf.runtime.diagram.core.providers; |
| |
| import java.util.ArrayList; |
| import java.util.HashMap; |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.Set; |
| |
| import org.eclipse.core.runtime.IAdaptable; |
| import org.eclipse.core.runtime.IConfigurationElement; |
| |
| import org.eclipse.gmf.runtime.common.core.service.AbstractProviderConfiguration; |
| import org.eclipse.gmf.runtime.notation.View; |
| |
| /** |
| * @author melaasar |
| * |
| * A provider configuration for the ViewService. It helps in filtering out |
| * and delay loading unrelated providers. |
| */ |
| public class ViewProviderConfiguration extends AbstractProviderConfiguration { |
| |
| /** constants corresponding to different symbols in the extention schema */ |
| private static final String CONTEXT = "context"; //$NON-NLS-1$ |
| private static final String VIEW_CLASS = "viewClass"; //$NON-NLS-1$ |
| private static final String ELEMENTS = "elements"; //$NON-NLS-1$ |
| private static final String CONTAINERVIEWS = "containerViews"; //$NON-NLS-1$ |
| private static final String SEMANTICHINTS = "semanticHints"; //$NON-NLS-1$ |
| |
| /** a map of requests supported by this provider to their target contexts*/ |
| private List requests = new ArrayList(); |
| |
| /** |
| * Builds a new provider contribution descriptor by parsing its configuration element |
| * |
| * @param configElement A provider configuration element |
| * @return A provider XML contribution descriptor |
| */ |
| public static ViewProviderConfiguration parse(IConfigurationElement configElement) { |
| assert null != configElement : "Null provider configuration elemen in ViewProviderConfiguration";//$NON-NLS-1$ |
| return new ViewProviderConfiguration(configElement); |
| } |
| |
| /** |
| * Creates a new <code>ProviderContributionDescriptor</code> instance |
| * given a provider configuration element |
| * |
| * @param configElement The provider XML configuration element |
| */ |
| private ViewProviderConfiguration(IConfigurationElement configElement) { |
| IConfigurationElement configChildren[]; |
| |
| // read the object descriptors |
| Map objects = new HashMap(); |
| configChildren = configElement.getChildren(OBJECT); |
| for (int i = 0; i < configChildren.length; i++) { |
| String id = configChildren[i].getAttribute(ID); |
| if (id != null) |
| objects.put(id, new ObjectDescriptor(configChildren[i])); |
| } |
| |
| // read the context descriptors |
| configChildren = configElement.getChildren(CONTEXT); |
| for (int i = 0; i < configChildren.length; i++) { |
| String viewClassName = configChildren[i].getAttribute(VIEW_CLASS); |
| List elements = |
| getObjectList( |
| configChildren[i].getAttribute(ELEMENTS), |
| objects, configElement); |
| List parentViews = |
| getObjectList( |
| configChildren[i].getAttribute(CONTAINERVIEWS), |
| objects, configElement); |
| Set semanticHints = |
| getStrings(configChildren[i].getAttribute(SEMANTICHINTS)); |
| if (viewClassName != null |
| || elements != null |
| || parentViews != null |
| || semanticHints != null) |
| requests.add( |
| new ContextDescriptor( |
| viewClassName, |
| elements, |
| parentViews, |
| semanticHints)); |
| } |
| } |
| |
| /** |
| * Determines if the provider understands the given context |
| * The provider understands the request if: |
| * 1- There are no listed provider contexts |
| * 2- The context matches one of the provider contexts |
| * |
| * @param viewKind The view kind |
| * @param semanticAdapter The semantic adapter |
| * @param containerView The container view |
| * @param semanticHint the factory hint |
| * @return boolean <code>true</code> if it supports; <code>false</code> otherwise |
| */ |
| public boolean supports( |
| Class viewKind, |
| IAdaptable semanticAdapter, |
| View containerView, |
| String semanticHint) { |
| if (requests.isEmpty()) |
| return true; |
| |
| for (Iterator iter = requests.iterator();iter.hasNext();) { |
| ContextDescriptor request = (ContextDescriptor) iter.next(); |
| if (request |
| .matches( |
| viewKind, |
| semanticAdapter, |
| containerView, |
| semanticHint)) |
| return true; |
| } |
| return false; |
| } |
| |
| /** |
| * A descriptor for a provider context |
| */ |
| private static class ContextDescriptor { |
| /** the view's kind class name */ |
| private String viewClassName; |
| /** the request's elements */ |
| private final List elements; |
| /** the request's parent views */ |
| private final List parentViews; |
| /** the request's semantic hints */ |
| private final Set semanticHints; |
| |
| /** |
| * creates a new context descriptor from some context |
| * |
| * @param viewKind The view kind |
| * @param semanticAdapter The semantic adapter |
| * @param containerView The container view |
| * @param semanticHint the factory hint |
| */ |
| public ContextDescriptor( |
| String viewClassName, |
| List elements, |
| List parentViews, |
| Set semanticHints) { |
| this.viewClassName = viewClassName; |
| this.elements = elements; |
| this.parentViews = parentViews; |
| this.semanticHints = semanticHints; |
| } |
| |
| /** |
| * Determines if the context descriptor matches the given context |
| * |
| * @param viewKind The view kind |
| * @param semanticAdapter The semantic adapter |
| * @param containerView The container view |
| * @param semanticHint the semantic hint |
| * @return boolean |
| */ |
| public boolean matches( |
| Class viewKind, |
| IAdaptable semanticAdapter, |
| View containerView, |
| String semanticHint) { |
| if (viewClassName != null) { |
| if (!viewClassName.equals(viewKind.getName())) |
| return false; |
| } |
| if (semanticHints != null) { |
| if (!semanticHints.contains(semanticHint)) |
| return false; |
| } |
| if (elements != null) { |
| if (!objectMatches(semanticAdapter, elements)) |
| return false; |
| } |
| if (parentViews != null) { |
| if (!objectMatches(containerView, parentViews)) |
| return false; |
| } |
| return true; |
| } |
| } |
| |
| } |