org.eclipse.mylyn.tasks.ui/src/org/eclipse/mylyn/internal/tasks/ui/util/TasksUiExtensionReader.java - mylyn/org.eclipse.mylyn.tasks - Git at Google

 /*******************************************************************************
  * Copyright (c) 2004, 2008 Tasktop Technologies 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:
  *     Tasktop Technologies - initial API and implementation
  *******************************************************************************/

 package org.eclipse.mylyn.internal.tasks.ui.util;

 import java.util.ArrayList;
 import java.util.List;

 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IConfigurationElement;
 import org.eclipse.core.runtime.IExtension;
 import org.eclipse.core.runtime.IExtensionPoint;
 import org.eclipse.core.runtime.IExtensionRegistry;
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.Platform;
 import org.eclipse.core.runtime.Status;
 import org.eclipse.jface.resource.ImageDescriptor;
 import org.eclipse.mylyn.commons.core.StatusHandler;
 import org.eclipse.mylyn.internal.provisional.commons.ui.CommonImages;
 import org.eclipse.mylyn.internal.tasks.core.externalization.TaskListExternalizer;
 import org.eclipse.mylyn.internal.tasks.ui.IDynamicSubMenuContributor;
 import org.eclipse.mylyn.internal.tasks.ui.TasksUiPlugin;
 import org.eclipse.mylyn.internal.tasks.ui.views.AbstractTaskListPresentation;
 import org.eclipse.mylyn.internal.tasks.ui.views.TaskListView;
 import org.eclipse.mylyn.tasks.core.AbstractDuplicateDetector;
 import org.eclipse.mylyn.tasks.core.AbstractRepositoryConnector;
 import org.eclipse.mylyn.tasks.core.AbstractTaskListMigrator;
 import org.eclipse.mylyn.tasks.core.RepositoryTemplate;
 import org.eclipse.mylyn.tasks.ui.AbstractRepositoryConnectorUi;
 import org.eclipse.mylyn.tasks.ui.AbstractTaskRepositoryLinkProvider;
 import org.eclipse.mylyn.tasks.ui.TasksUi;
 import org.eclipse.mylyn.tasks.ui.editors.AbstractTaskEditorPageFactory;
 import org.eclipse.ui.plugin.AbstractUIPlugin;

 /**
  * @author Mik Kersten
  * @author Shawn Minto
  * @author Rob Elves
  */
 public class TasksUiExtensionReader {

 	public static final String EXTENSION_REPOSITORIES = "org.eclipse.mylyn.tasks.ui.repositories"; //$NON-NLS-1$

 	public static final String EXTENSION_REPOSITORY_LINKS_PROVIDERS = "org.eclipse.mylyn.tasks.ui.projectLinkProviders"; //$NON-NLS-1$

 	public static final String EXTENSION_TEMPLATES = "org.eclipse.mylyn.tasks.core.templates"; //$NON-NLS-1$

 	public static final String EXTENSION_TMPL_REPOSITORY = "repository"; //$NON-NLS-1$

 	public static final String ELMNT_TMPL_LABEL = "label"; //$NON-NLS-1$

 	public static final String ELMNT_TMPL_URLREPOSITORY = "urlRepository"; //$NON-NLS-1$

 	public static final String ELMNT_TMPL_REPOSITORYKIND = "repositoryKind"; //$NON-NLS-1$

 	public static final String ELMNT_TMPL_CHARACTERENCODING = "characterEncoding"; //$NON-NLS-1$

 	public static final String ELMNT_TMPL_ANONYMOUS = "anonymous"; //$NON-NLS-1$

 	public static final String ELMNT_TMPL_VERSION = "version"; //$NON-NLS-1$

 	public static final String ELMNT_TMPL_URLNEWTASK = "urlNewTask"; //$NON-NLS-1$

 	public static final String ELMNT_TMPL_URLTASK = "urlTask"; //$NON-NLS-1$

 	public static final String ELMNT_TMPL_URLTASKQUERY = "urlTaskQuery"; //$NON-NLS-1$

 	public static final String ELMNT_TMPL_NEWACCOUNTURL = "urlNewAccount"; //$NON-NLS-1$

 	public static final String ELMNT_TMPL_ADDAUTO = "addAutomatically"; //$NON-NLS-1$

 	public static final String ELMNT_REPOSITORY_CONNECTOR = "connectorCore"; //$NON-NLS-1$

 	public static final String ELMNT_REPOSITORY_LINK_PROVIDER = "linkProvider"; //$NON-NLS-1$

 	public static final String ELMNT_REPOSITORY_UI = "connectorUi"; //$NON-NLS-1$

 	public static final String ELMNT_MIGRATOR = "taskListMigrator"; //$NON-NLS-1$

 	public static final String ATTR_BRANDING_ICON = "brandingIcon"; //$NON-NLS-1$

 	public static final String ATTR_OVERLAY_ICON = "overlayIcon"; //$NON-NLS-1$

 	public static final String ELMNT_TYPE = "type"; //$NON-NLS-1$

 	public static final String ELMNT_QUERY_PAGE = "queryPage"; //$NON-NLS-1$

 	public static final String ELMNT_SETTINGS_PAGE = "settingsPage"; //$NON-NLS-1$

 	public static final String EXTENSION_TASK_CONTRIBUTOR = "org.eclipse.mylyn.tasks.ui.actions"; //$NON-NLS-1$

 	public static final String ATTR_ACTION_CONTRIBUTOR_CLASS = "taskHandlerClass"; //$NON-NLS-1$

 	public static final String DYNAMIC_POPUP_ELEMENT = "dynamicPopupMenu"; //$NON-NLS-1$

 	public static final String ATTR_CLASS = "class"; //$NON-NLS-1$

 	public static final String ATTR_MENU_PATH = "menuPath"; //$NON-NLS-1$

 	public static final String EXTENSION_EDITORS = "org.eclipse.mylyn.tasks.ui.editors"; //$NON-NLS-1$

 	public static final String ELMNT_TASK_EDITOR_PAGE_FACTORY = "pageFactory"; //$NON-NLS-1$

 	public static final String EXTENSION_DUPLICATE_DETECTORS = "org.eclipse.mylyn.tasks.ui.duplicateDetectors"; //$NON-NLS-1$

 	public static final String ELMNT_DUPLICATE_DETECTOR = "detector"; //$NON-NLS-1$

 	public static final String ATTR_NAME = "name"; //$NON-NLS-1$

 	public static final String ATTR_KIND = "kind"; //$NON-NLS-1$

 	private static final String EXTENSION_PRESENTATIONS = "org.eclipse.mylyn.tasks.ui.presentations"; //$NON-NLS-1$

 	public static final String ELMNT_PRESENTATION = "presentation"; //$NON-NLS-1$

 	public static final String ATTR_ICON = "icon"; //$NON-NLS-1$

 	public static final String ATTR_PRIMARY = "primary"; //$NON-NLS-1$

 	public static final String ATTR_ID = "id"; //$NON-NLS-1$

 	private static boolean coreExtensionsRead = false;

 	public static void initStartupExtensions(TaskListExternalizer taskListExternalizer) {
 		if (!coreExtensionsRead) {
 			IExtensionRegistry registry = Platform.getExtensionRegistry();

 			// NOTE: has to be read first, consider improving
 			List<AbstractTaskListMigrator> migrators = new ArrayList<AbstractTaskListMigrator>();
 			IExtensionPoint repositoriesExtensionPoint = registry.getExtensionPoint(EXTENSION_REPOSITORIES);
 			IExtension[] repositoryExtensions = repositoriesExtensionPoint.getExtensions();
 			for (IExtension repositoryExtension : repositoryExtensions) {
 				IConfigurationElement[] elements = repositoryExtension.getConfigurationElements();
 				for (IConfigurationElement element : elements) {
 					if (element.getName().equals(ELMNT_REPOSITORY_CONNECTOR)) {
 						readRepositoryConnectorCore(element);
 					} else if (element.getName().equals(ELMNT_MIGRATOR)) {
 						readMigrator(element, migrators);
 					}
 				}
 			}
 			taskListExternalizer.initialize(migrators);

 			IExtensionPoint templatesExtensionPoint = registry.getExtensionPoint(EXTENSION_TEMPLATES);
 			IExtension[] templateExtensions = templatesExtensionPoint.getExtensions();
 			for (IExtension templateExtension : templateExtensions) {
 				IConfigurationElement[] elements = templateExtension.getConfigurationElements();
 				for (IConfigurationElement element : elements) {
 					if (element.getName().equals(EXTENSION_TMPL_REPOSITORY)) {
 						readRepositoryTemplate(element);
 					}
 				}
 			}

 			IExtensionPoint presentationsExtensionPoint = registry.getExtensionPoint(EXTENSION_PRESENTATIONS);
 			IExtension[] presentations = presentationsExtensionPoint.getExtensions();
 			for (IExtension presentation : presentations) {
 				IConfigurationElement[] elements = presentation.getConfigurationElements();
 				for (IConfigurationElement element : elements) {
 					readPresentation(element);
 				}
 			}

 			// NOTE: causes ..mylyn.context.ui to load
 			IExtensionPoint editorsExtensionPoint = registry.getExtensionPoint(EXTENSION_EDITORS);
 			IExtension[] editors = editorsExtensionPoint.getExtensions();
 			for (IExtension editor : editors) {
 				IConfigurationElement[] elements = editor.getConfigurationElements();
 				for (IConfigurationElement element : elements) {
 					if (element.getName().equals(ELMNT_TASK_EDITOR_PAGE_FACTORY)) {
 						readTaskEditorPageFactory(element);
 					}
 				}
 			}

 			coreExtensionsRead = true;
 		}
 	}

 	public static void initWorkbenchUiExtensions() {
 		IExtensionRegistry registry = Platform.getExtensionRegistry();

 		IExtensionPoint repositoriesExtensionPoint = registry.getExtensionPoint(EXTENSION_REPOSITORIES);
 		IExtension[] repositoryExtensions = repositoriesExtensionPoint.getExtensions();
 		for (IExtension repositoryExtension : repositoryExtensions) {
 			IConfigurationElement[] elements = repositoryExtension.getConfigurationElements();
 			for (IConfigurationElement element : elements) {
 				if (element.getName().equals(ELMNT_REPOSITORY_UI)) {
 					readRepositoryConnectorUi(element);
 				}
 			}
 		}

 		IExtensionPoint linkProvidersExtensionPoint = registry.getExtensionPoint(EXTENSION_REPOSITORY_LINKS_PROVIDERS);
 		IExtension[] linkProvidersExtensions = linkProvidersExtensionPoint.getExtensions();
 		for (IExtension linkProvidersExtension : linkProvidersExtensions) {
 			IConfigurationElement[] elements = linkProvidersExtension.getConfigurationElements();
 			for (IConfigurationElement element : elements) {
 				if (element.getName().equals(ELMNT_REPOSITORY_LINK_PROVIDER)) {
 					readLinkProvider(element);
 				}
 			}
 		}

 		IExtensionPoint duplicateDetectorsExtensionPoint = registry.getExtensionPoint(EXTENSION_DUPLICATE_DETECTORS);
 		IExtension[] dulicateDetectorsExtensions = duplicateDetectorsExtensionPoint.getExtensions();
 		for (IExtension dulicateDetectorsExtension : dulicateDetectorsExtensions) {
 			IConfigurationElement[] elements = dulicateDetectorsExtension.getConfigurationElements();
 			for (IConfigurationElement element : elements) {
 				if (element.getName().equals(ELMNT_DUPLICATE_DETECTOR)) {
 					readDuplicateDetector(element);
 				}
 			}
 		}

 		IExtensionPoint extensionPoint = registry.getExtensionPoint(EXTENSION_TASK_CONTRIBUTOR);
 		IExtension[] extensions = extensionPoint.getExtensions();
 		for (IExtension extension : extensions) {
 			IConfigurationElement[] elements = extension.getConfigurationElements();
 			for (IConfigurationElement element : elements) {
 				if (element.getName().equals(DYNAMIC_POPUP_ELEMENT)) {
 					readDynamicPopupContributor(element);
 				}
 			}
 		}
 	}

 	private static void readPresentation(IConfigurationElement element) {
 		try {
 			String name = element.getAttribute(ATTR_NAME);

 			String iconPath = element.getAttribute(ATTR_ICON);
 			ImageDescriptor imageDescriptor = AbstractUIPlugin.imageDescriptorFromPlugin( //
 					element.getContributor().getName(), iconPath);
 			AbstractTaskListPresentation presentation = (AbstractTaskListPresentation) element.createExecutableExtension(ATTR_CLASS);
 			presentation.setImageDescriptor(imageDescriptor);
 			presentation.setName(name);

 			String primary = element.getAttribute(ATTR_PRIMARY);
 			if (primary != null && primary.equals("true")) { //$NON-NLS-1$
 				presentation.setPrimary(true);
 			}

 			TaskListView.addPresentation(presentation);
 		} catch (CoreException e) {
 			StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN,
 					"Could not load presentation extension", e)); //$NON-NLS-1$
 		}
 	}

 	private static void readDuplicateDetector(IConfigurationElement element) {
 		try {
 			Object obj = element.createExecutableExtension(ATTR_CLASS);
 			if (obj instanceof AbstractDuplicateDetector) {
 				AbstractDuplicateDetector duplicateDetector = (AbstractDuplicateDetector) obj;
 				duplicateDetector.setName(element.getAttribute(ATTR_NAME));
 				duplicateDetector.setConnectorKind(element.getAttribute(ATTR_KIND));
 				TasksUiPlugin.getDefault().addDuplicateDetector(duplicateDetector);
 			} else {
 				StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN,
 						"Could not load duplicate detector " + obj.getClass().getCanonicalName())); //$NON-NLS-1$
 			}
 		} catch (CoreException e) {
 			StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN, "Could not load duplicate detector", e)); //$NON-NLS-1$
 		}
 	}

 	private static void readLinkProvider(IConfigurationElement element) {
 		try {
 			Object repositoryLinkProvider = element.createExecutableExtension(ATTR_CLASS);
 			if (repositoryLinkProvider instanceof AbstractTaskRepositoryLinkProvider) {
 				TasksUiPlugin.getDefault().addRepositoryLinkProvider(
 						(AbstractTaskRepositoryLinkProvider) repositoryLinkProvider);
 			} else {
 				StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN,
 						"Could not load repository link provider " //$NON-NLS-1$
 								+ repositoryLinkProvider.getClass().getCanonicalName()));
 			}
 		} catch (CoreException e) {
 			StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN,
 					"Could not load repository link provider", e)); //$NON-NLS-1$
 		}
 	}

 	private static void readTaskEditorPageFactory(IConfigurationElement element) {
 		String id = element.getAttribute(ATTR_ID);
 		if (id == null) {
 			StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN, "Editor page factory must specify id")); //$NON-NLS-1$
 			return;
 		}

 		try {
 			Object item = element.createExecutableExtension(ATTR_CLASS);
 			if (item instanceof AbstractTaskEditorPageFactory) {
 				AbstractTaskEditorPageFactory editorPageFactory = (AbstractTaskEditorPageFactory) item;
 				editorPageFactory.setId(id);
 				TasksUiPlugin.getDefault().addTaskEditorPageFactory(editorPageFactory);
 			} else {
 				StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN,
 						"Could not load editor page factory " + item.getClass().getCanonicalName() + " must implement " //$NON-NLS-1$ //$NON-NLS-2$
 								+ AbstractTaskEditorPageFactory.class.getCanonicalName()));
 			}
 		} catch (CoreException e) {
 			StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN, "Could not load page editor factory", //$NON-NLS-1$
 					e));
 		}
 	}

 	private static void readRepositoryConnectorCore(IConfigurationElement element) {
 		try {
 			Object connectorCore = element.createExecutableExtension(ATTR_CLASS);
 			if (connectorCore instanceof AbstractRepositoryConnector) {
 				AbstractRepositoryConnector repositoryConnector = (AbstractRepositoryConnector) connectorCore;
 				TasksUiPlugin.getRepositoryManager().addRepositoryConnector(repositoryConnector);
 			} else {
 				StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN, "Could not load connector core " //$NON-NLS-1$
 						+ connectorCore.getClass().getCanonicalName()));
 			}
 		} catch (CoreException e) {
 			StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN, "Could not load connector core", e)); //$NON-NLS-1$
 		}
 	}

 	private static void readRepositoryConnectorUi(IConfigurationElement element) {
 		try {
 			Object connectorUiObject = element.createExecutableExtension(ATTR_CLASS);
 			if (connectorUiObject instanceof AbstractRepositoryConnectorUi) {
 				AbstractRepositoryConnectorUi connectorUi = (AbstractRepositoryConnectorUi) connectorUiObject;
 				TasksUiPlugin.getDefault().addRepositoryConnectorUi(connectorUi);

 				String iconPath = element.getAttribute(ATTR_BRANDING_ICON);
 				if (iconPath != null) {
 					ImageDescriptor descriptor = AbstractUIPlugin.imageDescriptorFromPlugin(element.getContributor()
 							.getName(), iconPath);
 					if (descriptor != null) {
 						TasksUiPlugin.getDefault().addBrandingIcon(connectorUi.getConnectorKind(),
 								CommonImages.getImage(descriptor));
 					}
 				}
 				String overlayIconPath = element.getAttribute(ATTR_OVERLAY_ICON);
 				if (overlayIconPath != null) {
 					ImageDescriptor descriptor = AbstractUIPlugin.imageDescriptorFromPlugin(element.getContributor()
 							.getName(), overlayIconPath);
 					if (descriptor != null) {
 						TasksUiPlugin.getDefault().addOverlayIcon(connectorUi.getConnectorKind(), descriptor);
 					}
 				}
 			} else {
 				StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN, "Could not load connector ui " //$NON-NLS-1$
 						+ connectorUiObject.getClass().getCanonicalName()));
 			}
 		} catch (CoreException e) {
 			StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN, "Could not load connector ui", e)); //$NON-NLS-1$
 		}
 	}

 	private static void readRepositoryTemplate(IConfigurationElement element) {
 		boolean anonymous = false;
 		boolean addAuto = false;

 		String label = element.getAttribute(ELMNT_TMPL_LABEL);
 		String serverUrl = element.getAttribute(ELMNT_TMPL_URLREPOSITORY);
 		String repKind = element.getAttribute(ELMNT_TMPL_REPOSITORYKIND);
 		String version = element.getAttribute(ELMNT_TMPL_VERSION);
 		String newTaskUrl = element.getAttribute(ELMNT_TMPL_URLNEWTASK);
 		String taskPrefix = element.getAttribute(ELMNT_TMPL_URLTASK);
 		String taskQueryUrl = element.getAttribute(ELMNT_TMPL_URLTASKQUERY);
 		String newAccountUrl = element.getAttribute(ELMNT_TMPL_NEWACCOUNTURL);
 		String encoding = element.getAttribute(ELMNT_TMPL_CHARACTERENCODING);
 		addAuto = Boolean.parseBoolean(element.getAttribute(ELMNT_TMPL_ADDAUTO));
 		anonymous = Boolean.parseBoolean(element.getAttribute(ELMNT_TMPL_ANONYMOUS));

 		if (serverUrl != null && label != null && repKind != null
 				&& TasksUi.getRepositoryManager().getRepositoryConnector(repKind) != null) {
 			RepositoryTemplate template = new RepositoryTemplate(label, serverUrl, encoding, version, newTaskUrl,
 					taskPrefix, taskQueryUrl, newAccountUrl, anonymous, addAuto);
 			TasksUiPlugin.getRepositoryTemplateManager().addTemplate(repKind, template);

 			for (IConfigurationElement configElement : element.getChildren()) {
 				String name = configElement.getAttribute("name"); //$NON-NLS-1$
 				String value = configElement.getAttribute("value"); //$NON-NLS-1$
 				if (name != null && !name.equals("") && value != null) { //$NON-NLS-1$
 					template.addAttribute(name, value);
 				}
 			}
 		} else {
 			// TODO change error message to include hints about the cause of the error
 			StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN,
 					"Could not load repository template extension " + element.getName())); //$NON-NLS-1$
 		}
 	}

 	private static void readDynamicPopupContributor(IConfigurationElement element) {
 		try {
 			Object dynamicPopupContributor = element.createExecutableExtension(ATTR_CLASS);
 			String menuPath = element.getAttribute(ATTR_MENU_PATH);
 			if (dynamicPopupContributor instanceof IDynamicSubMenuContributor) {
 				TasksUiPlugin.getDefault().addDynamicPopupContributor(menuPath,
 						(IDynamicSubMenuContributor) dynamicPopupContributor);
 			} else {
 				StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN,
 						"Could not load dynamic popup menu: " + dynamicPopupContributor.getClass().getCanonicalName() //$NON-NLS-1$
 								+ " must implement " + IDynamicSubMenuContributor.class.getCanonicalName())); //$NON-NLS-1$
 			}
 		} catch (CoreException e) {
 			StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN,
 					"Could not load dynamic popup menu extension", e)); //$NON-NLS-1$
 		}
 	}

 	private static void readMigrator(IConfigurationElement element, List<AbstractTaskListMigrator> migrators) {
 		try {
 			Object migratorObject = element.createExecutableExtension(ATTR_CLASS);
 			if (migratorObject instanceof AbstractTaskListMigrator) {
 				AbstractTaskListMigrator migrator = (AbstractTaskListMigrator) migratorObject;
 				migrators.add(migrator);
 			} else {
 				StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN,
 						"Could not load task list migrator migrator: " + migratorObject.getClass().getCanonicalName() //$NON-NLS-1$
 								+ " must implement " + AbstractTaskListMigrator.class.getCanonicalName())); //$NON-NLS-1$
 			}
 		} catch (CoreException e) {
 			StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN,
 					"Could not load task list migrator extension", e)); //$NON-NLS-1$
 		}
 	}

 }
	/*******************************************************************************
	* Copyright (c) 2004, 2008 Tasktop Technologies 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:
	* Tasktop Technologies - initial API and implementation
	*******************************************************************************/

	package org.eclipse.mylyn.internal.tasks.ui.util;

	import java.util.ArrayList;
	import java.util.List;

	import org.eclipse.core.runtime.CoreException;
	import org.eclipse.core.runtime.IConfigurationElement;
	import org.eclipse.core.runtime.IExtension;
	import org.eclipse.core.runtime.IExtensionPoint;
	import org.eclipse.core.runtime.IExtensionRegistry;
	import org.eclipse.core.runtime.IStatus;
	import org.eclipse.core.runtime.Platform;
	import org.eclipse.core.runtime.Status;
	import org.eclipse.jface.resource.ImageDescriptor;
	import org.eclipse.mylyn.commons.core.StatusHandler;
	import org.eclipse.mylyn.internal.provisional.commons.ui.CommonImages;
	import org.eclipse.mylyn.internal.tasks.core.externalization.TaskListExternalizer;
	import org.eclipse.mylyn.internal.tasks.ui.IDynamicSubMenuContributor;
	import org.eclipse.mylyn.internal.tasks.ui.TasksUiPlugin;
	import org.eclipse.mylyn.internal.tasks.ui.views.AbstractTaskListPresentation;
	import org.eclipse.mylyn.internal.tasks.ui.views.TaskListView;
	import org.eclipse.mylyn.tasks.core.AbstractDuplicateDetector;
	import org.eclipse.mylyn.tasks.core.AbstractRepositoryConnector;
	import org.eclipse.mylyn.tasks.core.AbstractTaskListMigrator;
	import org.eclipse.mylyn.tasks.core.RepositoryTemplate;
	import org.eclipse.mylyn.tasks.ui.AbstractRepositoryConnectorUi;
	import org.eclipse.mylyn.tasks.ui.AbstractTaskRepositoryLinkProvider;
	import org.eclipse.mylyn.tasks.ui.TasksUi;
	import org.eclipse.mylyn.tasks.ui.editors.AbstractTaskEditorPageFactory;
	import org.eclipse.ui.plugin.AbstractUIPlugin;

	/**
	* @author Mik Kersten
	* @author Shawn Minto
	* @author Rob Elves
	*/
	public class TasksUiExtensionReader {

	public static final String EXTENSION_REPOSITORIES = "org.eclipse.mylyn.tasks.ui.repositories"; //$NON-NLS-1$

	public static final String EXTENSION_REPOSITORY_LINKS_PROVIDERS = "org.eclipse.mylyn.tasks.ui.projectLinkProviders"; //$NON-NLS-1$

	public static final String EXTENSION_TEMPLATES = "org.eclipse.mylyn.tasks.core.templates"; //$NON-NLS-1$

	public static final String EXTENSION_TMPL_REPOSITORY = "repository"; //$NON-NLS-1$

	public static final String ELMNT_TMPL_LABEL = "label"; //$NON-NLS-1$

	public static final String ELMNT_TMPL_URLREPOSITORY = "urlRepository"; //$NON-NLS-1$

	public static final String ELMNT_TMPL_REPOSITORYKIND = "repositoryKind"; //$NON-NLS-1$

	public static final String ELMNT_TMPL_CHARACTERENCODING = "characterEncoding"; //$NON-NLS-1$

	public static final String ELMNT_TMPL_ANONYMOUS = "anonymous"; //$NON-NLS-1$

	public static final String ELMNT_TMPL_VERSION = "version"; //$NON-NLS-1$

	public static final String ELMNT_TMPL_URLNEWTASK = "urlNewTask"; //$NON-NLS-1$

	public static final String ELMNT_TMPL_URLTASK = "urlTask"; //$NON-NLS-1$

	public static final String ELMNT_TMPL_URLTASKQUERY = "urlTaskQuery"; //$NON-NLS-1$

	public static final String ELMNT_TMPL_NEWACCOUNTURL = "urlNewAccount"; //$NON-NLS-1$

	public static final String ELMNT_TMPL_ADDAUTO = "addAutomatically"; //$NON-NLS-1$

	public static final String ELMNT_REPOSITORY_CONNECTOR = "connectorCore"; //$NON-NLS-1$

	public static final String ELMNT_REPOSITORY_LINK_PROVIDER = "linkProvider"; //$NON-NLS-1$

	public static final String ELMNT_REPOSITORY_UI = "connectorUi"; //$NON-NLS-1$

	public static final String ELMNT_MIGRATOR = "taskListMigrator"; //$NON-NLS-1$

	public static final String ATTR_BRANDING_ICON = "brandingIcon"; //$NON-NLS-1$

	public static final String ATTR_OVERLAY_ICON = "overlayIcon"; //$NON-NLS-1$

	public static final String ELMNT_TYPE = "type"; //$NON-NLS-1$

	public static final String ELMNT_QUERY_PAGE = "queryPage"; //$NON-NLS-1$

	public static final String ELMNT_SETTINGS_PAGE = "settingsPage"; //$NON-NLS-1$

	public static final String EXTENSION_TASK_CONTRIBUTOR = "org.eclipse.mylyn.tasks.ui.actions"; //$NON-NLS-1$

	public static final String ATTR_ACTION_CONTRIBUTOR_CLASS = "taskHandlerClass"; //$NON-NLS-1$

	public static final String DYNAMIC_POPUP_ELEMENT = "dynamicPopupMenu"; //$NON-NLS-1$

	public static final String ATTR_CLASS = "class"; //$NON-NLS-1$

	public static final String ATTR_MENU_PATH = "menuPath"; //$NON-NLS-1$

	public static final String EXTENSION_EDITORS = "org.eclipse.mylyn.tasks.ui.editors"; //$NON-NLS-1$

	public static final String ELMNT_TASK_EDITOR_PAGE_FACTORY = "pageFactory"; //$NON-NLS-1$

	public static final String EXTENSION_DUPLICATE_DETECTORS = "org.eclipse.mylyn.tasks.ui.duplicateDetectors"; //$NON-NLS-1$

	public static final String ELMNT_DUPLICATE_DETECTOR = "detector"; //$NON-NLS-1$

	public static final String ATTR_NAME = "name"; //$NON-NLS-1$

	public static final String ATTR_KIND = "kind"; //$NON-NLS-1$

	private static final String EXTENSION_PRESENTATIONS = "org.eclipse.mylyn.tasks.ui.presentations"; //$NON-NLS-1$

	public static final String ELMNT_PRESENTATION = "presentation"; //$NON-NLS-1$

	public static final String ATTR_ICON = "icon"; //$NON-NLS-1$

	public static final String ATTR_PRIMARY = "primary"; //$NON-NLS-1$

	public static final String ATTR_ID = "id"; //$NON-NLS-1$

	private static boolean coreExtensionsRead = false;

	public static void initStartupExtensions(TaskListExternalizer taskListExternalizer) {
	if (!coreExtensionsRead) {
	IExtensionRegistry registry = Platform.getExtensionRegistry();

	// NOTE: has to be read first, consider improving
	List<AbstractTaskListMigrator> migrators = new ArrayList<AbstractTaskListMigrator>();
	IExtensionPoint repositoriesExtensionPoint = registry.getExtensionPoint(EXTENSION_REPOSITORIES);
	IExtension[] repositoryExtensions = repositoriesExtensionPoint.getExtensions();
	for (IExtension repositoryExtension : repositoryExtensions) {
	IConfigurationElement[] elements = repositoryExtension.getConfigurationElements();
	for (IConfigurationElement element : elements) {
	if (element.getName().equals(ELMNT_REPOSITORY_CONNECTOR)) {
	readRepositoryConnectorCore(element);
	} else if (element.getName().equals(ELMNT_MIGRATOR)) {
	readMigrator(element, migrators);
	}
	}
	}
	taskListExternalizer.initialize(migrators);

	IExtensionPoint templatesExtensionPoint = registry.getExtensionPoint(EXTENSION_TEMPLATES);
	IExtension[] templateExtensions = templatesExtensionPoint.getExtensions();
	for (IExtension templateExtension : templateExtensions) {
	IConfigurationElement[] elements = templateExtension.getConfigurationElements();
	for (IConfigurationElement element : elements) {
	if (element.getName().equals(EXTENSION_TMPL_REPOSITORY)) {
	readRepositoryTemplate(element);
	}
	}
	}

	IExtensionPoint presentationsExtensionPoint = registry.getExtensionPoint(EXTENSION_PRESENTATIONS);
	IExtension[] presentations = presentationsExtensionPoint.getExtensions();
	for (IExtension presentation : presentations) {
	IConfigurationElement[] elements = presentation.getConfigurationElements();
	for (IConfigurationElement element : elements) {
	readPresentation(element);
	}
	}

	// NOTE: causes ..mylyn.context.ui to load
	IExtensionPoint editorsExtensionPoint = registry.getExtensionPoint(EXTENSION_EDITORS);
	IExtension[] editors = editorsExtensionPoint.getExtensions();
	for (IExtension editor : editors) {
	IConfigurationElement[] elements = editor.getConfigurationElements();
	for (IConfigurationElement element : elements) {
	if (element.getName().equals(ELMNT_TASK_EDITOR_PAGE_FACTORY)) {
	readTaskEditorPageFactory(element);
	}
	}
	}

	coreExtensionsRead = true;
	}
	}

	public static void initWorkbenchUiExtensions() {
	IExtensionRegistry registry = Platform.getExtensionRegistry();

	IExtensionPoint repositoriesExtensionPoint = registry.getExtensionPoint(EXTENSION_REPOSITORIES);
	IExtension[] repositoryExtensions = repositoriesExtensionPoint.getExtensions();
	for (IExtension repositoryExtension : repositoryExtensions) {
	IConfigurationElement[] elements = repositoryExtension.getConfigurationElements();
	for (IConfigurationElement element : elements) {
	if (element.getName().equals(ELMNT_REPOSITORY_UI)) {
	readRepositoryConnectorUi(element);
	}
	}
	}

	IExtensionPoint linkProvidersExtensionPoint = registry.getExtensionPoint(EXTENSION_REPOSITORY_LINKS_PROVIDERS);
	IExtension[] linkProvidersExtensions = linkProvidersExtensionPoint.getExtensions();
	for (IExtension linkProvidersExtension : linkProvidersExtensions) {
	IConfigurationElement[] elements = linkProvidersExtension.getConfigurationElements();
	for (IConfigurationElement element : elements) {
	if (element.getName().equals(ELMNT_REPOSITORY_LINK_PROVIDER)) {
	readLinkProvider(element);
	}
	}
	}

	IExtensionPoint duplicateDetectorsExtensionPoint = registry.getExtensionPoint(EXTENSION_DUPLICATE_DETECTORS);
	IExtension[] dulicateDetectorsExtensions = duplicateDetectorsExtensionPoint.getExtensions();
	for (IExtension dulicateDetectorsExtension : dulicateDetectorsExtensions) {
	IConfigurationElement[] elements = dulicateDetectorsExtension.getConfigurationElements();
	for (IConfigurationElement element : elements) {
	if (element.getName().equals(ELMNT_DUPLICATE_DETECTOR)) {
	readDuplicateDetector(element);
	}
	}
	}

	IExtensionPoint extensionPoint = registry.getExtensionPoint(EXTENSION_TASK_CONTRIBUTOR);
	IExtension[] extensions = extensionPoint.getExtensions();
	for (IExtension extension : extensions) {
	IConfigurationElement[] elements = extension.getConfigurationElements();
	for (IConfigurationElement element : elements) {
	if (element.getName().equals(DYNAMIC_POPUP_ELEMENT)) {
	readDynamicPopupContributor(element);
	}
	}
	}
	}

	private static void readPresentation(IConfigurationElement element) {
	try {
	String name = element.getAttribute(ATTR_NAME);

	String iconPath = element.getAttribute(ATTR_ICON);
	ImageDescriptor imageDescriptor = AbstractUIPlugin.imageDescriptorFromPlugin( //
	element.getContributor().getName(), iconPath);
	AbstractTaskListPresentation presentation = (AbstractTaskListPresentation) element.createExecutableExtension(ATTR_CLASS);
	presentation.setImageDescriptor(imageDescriptor);
	presentation.setName(name);

	String primary = element.getAttribute(ATTR_PRIMARY);
	if (primary != null && primary.equals("true")) { //$NON-NLS-1$
	presentation.setPrimary(true);
	}

	TaskListView.addPresentation(presentation);
	} catch (CoreException e) {
	StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN,
	"Could not load presentation extension", e)); //$NON-NLS-1$
	}
	}

	private static void readDuplicateDetector(IConfigurationElement element) {
	try {
	Object obj = element.createExecutableExtension(ATTR_CLASS);
	if (obj instanceof AbstractDuplicateDetector) {
	AbstractDuplicateDetector duplicateDetector = (AbstractDuplicateDetector) obj;
	duplicateDetector.setName(element.getAttribute(ATTR_NAME));
	duplicateDetector.setConnectorKind(element.getAttribute(ATTR_KIND));
	TasksUiPlugin.getDefault().addDuplicateDetector(duplicateDetector);
	} else {
	StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN,
	"Could not load duplicate detector " + obj.getClass().getCanonicalName())); //$NON-NLS-1$
	}
	} catch (CoreException e) {
	StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN, "Could not load duplicate detector", e)); //$NON-NLS-1$
	}
	}

	private static void readLinkProvider(IConfigurationElement element) {
	try {
	Object repositoryLinkProvider = element.createExecutableExtension(ATTR_CLASS);
	if (repositoryLinkProvider instanceof AbstractTaskRepositoryLinkProvider) {
	TasksUiPlugin.getDefault().addRepositoryLinkProvider(
	(AbstractTaskRepositoryLinkProvider) repositoryLinkProvider);
	} else {
	StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN,
	"Could not load repository link provider " //$NON-NLS-1$
	+ repositoryLinkProvider.getClass().getCanonicalName()));
	}
	} catch (CoreException e) {
	StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN,
	"Could not load repository link provider", e)); //$NON-NLS-1$
	}
	}

	private static void readTaskEditorPageFactory(IConfigurationElement element) {
	String id = element.getAttribute(ATTR_ID);
	if (id == null) {
	StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN, "Editor page factory must specify id")); //$NON-NLS-1$
	return;
	}

	try {
	Object item = element.createExecutableExtension(ATTR_CLASS);
	if (item instanceof AbstractTaskEditorPageFactory) {
	AbstractTaskEditorPageFactory editorPageFactory = (AbstractTaskEditorPageFactory) item;
	editorPageFactory.setId(id);
	TasksUiPlugin.getDefault().addTaskEditorPageFactory(editorPageFactory);
	} else {
	StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN,
	"Could not load editor page factory " + item.getClass().getCanonicalName() + " must implement " //$NON-NLS-1$ //$NON-NLS-2$
	+ AbstractTaskEditorPageFactory.class.getCanonicalName()));
	}
	} catch (CoreException e) {
	StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN, "Could not load page editor factory", //$NON-NLS-1$
	e));
	}
	}

	private static void readRepositoryConnectorCore(IConfigurationElement element) {
	try {
	Object connectorCore = element.createExecutableExtension(ATTR_CLASS);
	if (connectorCore instanceof AbstractRepositoryConnector) {
	AbstractRepositoryConnector repositoryConnector = (AbstractRepositoryConnector) connectorCore;
	TasksUiPlugin.getRepositoryManager().addRepositoryConnector(repositoryConnector);
	} else {
	StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN, "Could not load connector core " //$NON-NLS-1$
	+ connectorCore.getClass().getCanonicalName()));
	}
	} catch (CoreException e) {
	StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN, "Could not load connector core", e)); //$NON-NLS-1$
	}
	}

	private static void readRepositoryConnectorUi(IConfigurationElement element) {
	try {
	Object connectorUiObject = element.createExecutableExtension(ATTR_CLASS);
	if (connectorUiObject instanceof AbstractRepositoryConnectorUi) {
	AbstractRepositoryConnectorUi connectorUi = (AbstractRepositoryConnectorUi) connectorUiObject;
	TasksUiPlugin.getDefault().addRepositoryConnectorUi(connectorUi);

	String iconPath = element.getAttribute(ATTR_BRANDING_ICON);
	if (iconPath != null) {
	ImageDescriptor descriptor = AbstractUIPlugin.imageDescriptorFromPlugin(element.getContributor()
	.getName(), iconPath);
	if (descriptor != null) {
	TasksUiPlugin.getDefault().addBrandingIcon(connectorUi.getConnectorKind(),
	CommonImages.getImage(descriptor));
	}
	}
	String overlayIconPath = element.getAttribute(ATTR_OVERLAY_ICON);
	if (overlayIconPath != null) {
	ImageDescriptor descriptor = AbstractUIPlugin.imageDescriptorFromPlugin(element.getContributor()
	.getName(), overlayIconPath);
	if (descriptor != null) {
	TasksUiPlugin.getDefault().addOverlayIcon(connectorUi.getConnectorKind(), descriptor);
	}
	}
	} else {
	StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN, "Could not load connector ui " //$NON-NLS-1$
	+ connectorUiObject.getClass().getCanonicalName()));
	}
	} catch (CoreException e) {
	StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN, "Could not load connector ui", e)); //$NON-NLS-1$
	}
	}

	private static void readRepositoryTemplate(IConfigurationElement element) {
	boolean anonymous = false;
	boolean addAuto = false;

	String label = element.getAttribute(ELMNT_TMPL_LABEL);
	String serverUrl = element.getAttribute(ELMNT_TMPL_URLREPOSITORY);
	String repKind = element.getAttribute(ELMNT_TMPL_REPOSITORYKIND);
	String version = element.getAttribute(ELMNT_TMPL_VERSION);
	String newTaskUrl = element.getAttribute(ELMNT_TMPL_URLNEWTASK);
	String taskPrefix = element.getAttribute(ELMNT_TMPL_URLTASK);
	String taskQueryUrl = element.getAttribute(ELMNT_TMPL_URLTASKQUERY);
	String newAccountUrl = element.getAttribute(ELMNT_TMPL_NEWACCOUNTURL);
	String encoding = element.getAttribute(ELMNT_TMPL_CHARACTERENCODING);
	addAuto = Boolean.parseBoolean(element.getAttribute(ELMNT_TMPL_ADDAUTO));
	anonymous = Boolean.parseBoolean(element.getAttribute(ELMNT_TMPL_ANONYMOUS));

	if (serverUrl != null && label != null && repKind != null
	&& TasksUi.getRepositoryManager().getRepositoryConnector(repKind) != null) {
	RepositoryTemplate template = new RepositoryTemplate(label, serverUrl, encoding, version, newTaskUrl,
	taskPrefix, taskQueryUrl, newAccountUrl, anonymous, addAuto);
	TasksUiPlugin.getRepositoryTemplateManager().addTemplate(repKind, template);

	for (IConfigurationElement configElement : element.getChildren()) {
	String name = configElement.getAttribute("name"); //$NON-NLS-1$
	String value = configElement.getAttribute("value"); //$NON-NLS-1$
	if (name != null && !name.equals("") && value != null) { //$NON-NLS-1$
	template.addAttribute(name, value);
	}
	}
	} else {
	// TODO change error message to include hints about the cause of the error
	StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN,
	"Could not load repository template extension " + element.getName())); //$NON-NLS-1$
	}
	}

	private static void readDynamicPopupContributor(IConfigurationElement element) {
	try {
	Object dynamicPopupContributor = element.createExecutableExtension(ATTR_CLASS);
	String menuPath = element.getAttribute(ATTR_MENU_PATH);
	if (dynamicPopupContributor instanceof IDynamicSubMenuContributor) {
	TasksUiPlugin.getDefault().addDynamicPopupContributor(menuPath,
	(IDynamicSubMenuContributor) dynamicPopupContributor);
	} else {
	StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN,
	"Could not load dynamic popup menu: " + dynamicPopupContributor.getClass().getCanonicalName() //$NON-NLS-1$
	+ " must implement " + IDynamicSubMenuContributor.class.getCanonicalName())); //$NON-NLS-1$
	}
	} catch (CoreException e) {
	StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN,
	"Could not load dynamic popup menu extension", e)); //$NON-NLS-1$
	}
	}

	private static void readMigrator(IConfigurationElement element, List<AbstractTaskListMigrator> migrators) {
	try {
	Object migratorObject = element.createExecutableExtension(ATTR_CLASS);
	if (migratorObject instanceof AbstractTaskListMigrator) {
	AbstractTaskListMigrator migrator = (AbstractTaskListMigrator) migratorObject;
	migrators.add(migrator);
	} else {
	StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN,
	"Could not load task list migrator migrator: " + migratorObject.getClass().getCanonicalName() //$NON-NLS-1$
	+ " must implement " + AbstractTaskListMigrator.class.getCanonicalName())); //$NON-NLS-1$
	}
	} catch (CoreException e) {
	StatusHandler.log(new Status(IStatus.ERROR, TasksUiPlugin.ID_PLUGIN,
	"Could not load task list migrator extension", e)); //$NON-NLS-1$
	}
	}

	}