--- /dev/null
+/*******************************************************************************\r
+ * Copyright (c) 2007, 2010 Association for Decentralized Information Management\r
+ * in Industry THTH ry.\r
+ * All rights reserved. This program and the accompanying materials\r
+ * are made available under the terms of the Eclipse Public License v1.0\r
+ * which accompanies this distribution, and is available at\r
+ * http://www.eclipse.org/legal/epl-v10.html\r
+ *\r
+ * Contributors:\r
+ * VTT Technical Research Centre of Finland - initial API and implementation\r
+ *******************************************************************************/\r
+package org.simantics.browsing.ui.common.extension.internal;\r
+\r
+import java.util.Arrays;\r
+import java.util.HashSet;\r
+import java.util.Set;\r
+\r
+import org.eclipse.core.runtime.CoreException;\r
+import org.eclipse.core.runtime.IConfigurationElement;\r
+import org.eclipse.core.runtime.IExtension;\r
+import org.eclipse.core.runtime.IExtensionPoint;\r
+import org.eclipse.core.runtime.Platform;\r
+import org.eclipse.core.runtime.dynamichelpers.ExtensionTracker;\r
+import org.eclipse.core.runtime.dynamichelpers.IExtensionChangeHandler;\r
+import org.eclipse.core.runtime.dynamichelpers.IExtensionTracker;\r
+import org.eclipse.core.runtime.dynamichelpers.IFilter;\r
+import org.simantics.browsing.ui.common.Activator;\r
+import org.simantics.browsing.ui.common.ErrorLogger;\r
+import org.simantics.browsing.ui.content.Contributor;\r
+import org.simantics.utils.strings.StringUtils;\r
+\r
+/**\r
+ * @author Tuukka Lehtonen\r
+ */\r
+public abstract class ContributorExtensionManager<Factory> implements IExtensionChangeHandler {\r
+\r
+ private final static String NAMESPACE = Activator.PLUGIN_ID;\r
+\r
+ private ExtensionTracker tracker;\r
+\r
+ @SuppressWarnings("unchecked")\r
+ ContributorExtension<Factory>[] extensions = new ContributorExtension[0];\r
+\r
+ abstract public String getExtensionPointName();\r
+\r
+ ContributorExtensionManager() {\r
+ tracker = new ExtensionTracker();\r
+\r
+ // Cache defined actions\r
+ IExtensionPoint expt = Platform.getExtensionRegistry().getExtensionPoint(NAMESPACE, getExtensionPointName());\r
+ loadExtensions(expt.getConfigurationElements());\r
+\r
+ // Start tracking for new and removed extensions\r
+ IFilter filter = ExtensionTracker.createExtensionPointFilter(expt);\r
+ tracker.registerHandler(this, filter);\r
+ }\r
+\r
+ @SuppressWarnings("unchecked")\r
+ void close() {\r
+ tracker.close();\r
+ tracker = null;\r
+ extensions = new ContributorExtension[0];\r
+ }\r
+\r
+ public ContributorExtension<Factory>[] getExtensions() {\r
+ return extensions;\r
+ }\r
+\r
+ @SuppressWarnings("unchecked")\r
+ private void loadExtensions(IConfigurationElement[] elements) {\r
+\r
+ Set<ContributorExtension<Factory>> newExtensions = new HashSet<ContributorExtension<Factory>>(Arrays.asList(extensions));\r
+\r
+ for (IConfigurationElement el : elements) {\r
+ try {\r
+\r
+ String id = StringUtils.safeString(el.getAttribute("id"));\r
+ Contributor<Factory> factory = (Contributor<Factory>)el.createExecutableExtension("class");\r
+ ContributorExtension<Factory> ext = new ContributorExtensionImpl<Factory>(id, factory);\r
+\r
+ // Start tracking the new extension object, its removal will be notified of\r
+ // with removeExtension(extension, Object[]).\r
+ tracker.registerObject(el.getDeclaringExtension(), ext, IExtensionTracker.REF_STRONG);\r
+\r
+ newExtensions.add(ext);\r
+ } catch (CoreException e) {\r
+ ErrorLogger.defaultLogError("Failed to initialize " + getExtensionPointName() + " extension \"" + el.getName()\r
+ + "\" with name \"" + el.getAttribute("name") + "\": "\r
+ + e.getMessage(), e);\r
+ }\r
+ }\r
+\r
+ // Atomic assignment\r
+ this.extensions = newExtensions.toArray(new ContributorExtension[newExtensions.size()]);\r
+ }\r
+\r
+ @Override\r
+ public void addExtension(IExtensionTracker tracker, IExtension extension) {\r
+ loadExtensions(extension.getConfigurationElements());\r
+ }\r
+\r
+ @SuppressWarnings("unchecked")\r
+ @Override\r
+ public void removeExtension(IExtension extension, Object[] objects) {\r
+ Set<ContributorExtension<Factory>> newExtensions = new HashSet<ContributorExtension<Factory>>(Arrays.asList(extensions));\r
+\r
+ for (Object o : objects) {\r
+ tracker.unregisterObject(extension, o);\r
+ newExtensions.remove(o);\r
+ }\r
+\r
+ // Atomic assignment\r
+ this.extensions = newExtensions.toArray(new ContributorExtension[newExtensions.size()]);\r
+ }\r
+\r
+}\r