--- /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.message.internal;\r
+\r
+import java.util.ArrayList;\r
+import java.util.Arrays;\r
+import java.util.HashMap;\r
+import java.util.HashSet;\r
+import java.util.Map;\r
+import java.util.Set;\r
+\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.message.IMessageDataSchemeExtension;\r
+import org.simantics.message.IMessageSchemeManager;\r
+\r
+/**\r
+ * @author Tuukka Lehtonen\r
+ */\r
+public class MessageSchemeManager implements IExtensionChangeHandler, IMessageSchemeManager {\r
+\r
+ public final static String NAMESPACE = "org.simantics.message";\r
+ public final static String ELEMENT_NAME = "scheme";\r
+ public final static String EP_NAME = "messageDataScheme";\r
+\r
+ private ExtensionTracker tracker;\r
+\r
+ private MessageDataSchemeExtension[] extensions = new MessageDataSchemeExtension[0];\r
+\r
+ public MessageSchemeManager() {\r
+ tracker = new ExtensionTracker();\r
+\r
+ // Cache defined actions\r
+ IExtensionPoint expt = Platform.getExtensionRegistry().getExtensionPoint(NAMESPACE, EP_NAME);\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
+ private String getDescription(IConfigurationElement el) {\r
+ for (IConfigurationElement desc : el.getChildren("description")) {\r
+ return desc.getValue();\r
+ }\r
+ return null;\r
+ }\r
+ \r
+ private void loadExtensions(IConfigurationElement[] configurationElements) {\r
+ Set<MessageDataSchemeExtension> newExtensions = new HashSet<MessageDataSchemeExtension>(Arrays.asList(extensions));\r
+ \r
+ // Initialize id -> extension lookup\r
+ Map<String, MessageDataSchemeExtension> schemes = new HashMap<String, MessageDataSchemeExtension>();\r
+ for (MessageDataSchemeExtension ext : newExtensions) {\r
+ schemes.put(ext.getId(), ext);\r
+ }\r
+\r
+ // 1st pass: load schemes\r
+ for (IConfigurationElement el : configurationElements) {\r
+ String name = el.getName();\r
+ if ("scheme".equals(name)) {\r
+ String id = el.getAttribute("id");\r
+ if (id == null)\r
+ continue;\r
+ String scheme = el.getAttribute("scheme");\r
+ if (scheme == null)\r
+ continue;\r
+ String description = getDescription(el);\r
+ \r
+ MessageDataSchemeExtension ext = schemes.get(id);\r
+ if (ext != null) {\r
+ // This scheme is already registered, two contributors are contributing the same scheme.\r
+ StringBuilder msg = new StringBuilder();\r
+ msg.append("Multiple contributors for message scheme '" + id + "':");\r
+ msg.append("\n 1st: " + ext.getSchemeElement().getContributor().getName());\r
+ msg.append("\n 2nd: " + el.getContributor().getName());\r
+ msg.append("\nUsing the first one.");\r
+ // TODO: proper logging\r
+ System.err.println(msg.toString());\r
+ continue;\r
+ }\r
+\r
+ ext = new MessageDataSchemeExtension(el, id, scheme, description);\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
+ schemes.put(id, ext);\r
+ }\r
+ }\r
+\r
+ // 2nd pass: load handlers\r
+ for (IConfigurationElement el : configurationElements) {\r
+ String name = el.getName();\r
+ if ("handler".equals(name)) {\r
+ String id = el.getAttribute("schemeId");\r
+ if (id == null)\r
+ continue;\r
+\r
+ MessageDataSchemeExtension ext = schemes.get(id);\r
+ if (ext == null) {\r
+ // Unusable handler since there is no scheme to use it for.\r
+ StringBuilder msg = new StringBuilder();\r
+ msg.append("No scheme extension for message scheme id '" + id + "'. Ignoring handler '" + el.getAttribute("handler") + "'");\r
+ msg.append("\nUsing the first one.");\r
+ // TODO: proper logging\r
+ System.err.println(msg.toString());\r
+ continue;\r
+ }\r
+\r
+ IConfigurationElement prev = ext.getHandlerElement();\r
+ if (prev != null) {\r
+ // Unusable handler since there already exists a handler for this scheme.\r
+ StringBuilder msg = new StringBuilder();\r
+ msg.append("Multiple handler contributors for message scheme '" + id + "':\n");\r
+ msg.append("\n 1st: " + prev.getContributor().getName());\r
+ msg.append("\n 2nd: " + el.getContributor().getName());\r
+ msg.append("\nUsing the first one.");\r
+ // TODO: proper logging\r
+ System.err.println(msg.toString());\r
+ continue;\r
+ }\r
+\r
+ ext.setHandlerElement(el);\r
+ }\r
+ }\r
+\r
+ // Atomic assignment\r
+ this.extensions = newExtensions.toArray(new MessageDataSchemeExtension[newExtensions.size()]);\r
+ }\r
+\r
+ @Override\r
+ public void addExtension(IExtensionTracker tracker, IExtension extension) {\r
+ loadExtensions(extension.getConfigurationElements());\r
+ }\r
+\r
+ @Override\r
+ public void removeExtension(IExtension extension, Object[] objects) {\r
+ Set<MessageDataSchemeExtension> newExtensions = new HashSet<MessageDataSchemeExtension>(Arrays.asList(extensions));\r
+\r
+ for (Object o : objects) {\r
+ tracker.unregisterObject(extension, o);\r
+ newExtensions.remove((IMessageDataSchemeExtension) o);\r
+ }\r
+\r
+ // Atomic assignment\r
+ this.extensions = newExtensions.toArray(new MessageDataSchemeExtension[newExtensions.size()]);\r
+ }\r
+\r
+ @Override\r
+ public IMessageDataSchemeExtension[] getByScheme(String scheme) {\r
+ if (scheme == null)\r
+ throw new IllegalArgumentException("null scheme");\r
+\r
+ ArrayList<MessageDataSchemeExtension> result = new ArrayList<MessageDataSchemeExtension>();\r
+ for (MessageDataSchemeExtension ext : extensions) {\r
+ if (scheme.equals(ext.getScheme()))\r
+ result.add(ext);\r
+ }\r
+ return result.toArray(new MessageDataSchemeExtension[result.size()]);\r
+ }\r
+\r
+}\r
Code Review / simantics / platform.git / blobdiff