org.eclipse.help.base/src/org/eclipse/help/internal/base/MissingContentManager.java - platform/eclipse.platform.ua - Git at Google

 /*******************************************************************************
  * Copyright (c) 2011, 2015 IBM Corporation and others.
  *
  * This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0
  * which accompanies this distribution, and is available at
  * https://www.eclipse.org/legal/epl-2.0/
  *
  * SPDX-License-Identifier: EPL-2.0
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *******************************************************************************/

 package org.eclipse.help.internal.base;

 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashSet;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Set;
 import java.util.StringTokenizer;

 import org.eclipse.core.runtime.IConfigurationElement;
 import org.eclipse.core.runtime.IExtensionRegistry;
 import org.eclipse.core.runtime.Platform;
 import org.eclipse.core.runtime.preferences.IEclipsePreferences;
 import org.eclipse.core.runtime.preferences.IScopeContext;
 import org.eclipse.core.runtime.preferences.InstanceScope;
 import org.eclipse.help.internal.HelpPlugin;
 import org.osgi.service.prefs.BackingStoreException;

 /**
  * Handles unresolved toc place holders as well as situations where remote help
  * is unavailable
  */

 public class MissingContentManager {

 	private static final String HELP_PROTOCOL = "help:"; //$NON-NLS-1$
 	private static final String EXTENSION_POINT_ID_TOC = HelpPlugin.PLUGIN_ID + ".toc"; //$NON-NLS-1$
 	private static final String ELEMENT_NAME_PLACEHOLDER = "placeholder"; //$NON-NLS-1$
 	private static final String ATTRIBUTE_NAME_PLUGIN = "plugin"; //$NON-NLS-1$
 	private static final String ATTRIBUTE_NAME_PLACEHOLDER_PAGE = "placeholderPage"; //$NON-NLS-1$
 	public static final String  IGNORE_MISSING_PLACEHOLDER_PREFERENCE = "ignorePlaceholders"; //$NON-NLS-1$

 	// Hrefs which are processed by org.eclipse.help.internal.webapp.StatusProducer
 	public static final String REMOTE_STATUS_HREF = "NetworkHelpStatus.html"; //$NON-NLS-1$
 	public static final String REMOTE_STATUS_HELP_VIEW_HREF = "NetworkHelpStatusHV.html"; //$NON-NLS-1$
 	public static final String MISSING_TOPIC_HREF = "MissingTopicStatus.html"; //$NON-NLS-1$
 	public static final String MISSING_TOPIC_PATH = "missingTopic/"; //$NON-NLS-1$
 	public static final String MISSING_BOOKS_HREF = "MissingBooks.html"; //$NON-NLS-1$
 	public static final String MISSING_BOOKS_HELP_VIEW_HREF = "MissingBooksHV.html"; //$NON-NLS-1$

 	/*
 	 * A place holder defines a page to be shown when a documentation page
 	 * which matches the specified path not installed
 	 */
 	public static class Placeholder implements Comparable<Placeholder> {
 		public String path;
 		public String bundle;
 		public String placeholderPage;

 		public Placeholder(String path, String bundle, String placeholderPage) {
 			this.path = path;
 			this.bundle = bundle;
 			this.placeholderPage = placeholderPage;
 		}

 		@Override
 		public int compareTo(Placeholder o) {
 			return o.path.compareTo(path);
 		}
 	}

 	private static MissingContentManager instance;
 	private List<Placeholder> placeholders;
     private Set<String> bundlesToIgnore; // A set of bundles the user does not want to see reference to

 	public static MissingContentManager getInstance() {
 		if ( instance == null ) {
 			instance = new MissingContentManager();
 		}
 		return instance;
 	}

 	/*
 	 * Read the extension registry
 	 */
 	private MissingContentManager() {
         IExtensionRegistry registry = Platform.getExtensionRegistry();
 		placeholders = new ArrayList<>();
 		bundlesToIgnore = new HashSet<>();
         if ( BaseHelpSystem.getMode() == BaseHelpSystem.MODE_INFOCENTER ) {
         	return; // Placeholders are not shown for infocenters
         }
         // Read the placeholders from the extension registry
 		IConfigurationElement[] elements = registry
 				.getConfigurationElementsFor(EXTENSION_POINT_ID_TOC);
 		for (int i = 0; i < elements.length; ++i) {
 			IConfigurationElement elem = elements[i];
 			String pluginId = elem.getContributor().getName();
 			if (elem.getName().equals(ELEMENT_NAME_PLACEHOLDER)) {
 				try {
 					String plugin = elem.getAttribute(ATTRIBUTE_NAME_PLUGIN);
 					String path = HELP_PROTOCOL  + plugin + '/';
 					String placeholder = elem
 							.getAttribute(ATTRIBUTE_NAME_PLACEHOLDER_PAGE);
 					placeholders.add(new Placeholder(path, plugin, placeholder));
 				} catch (Exception e) {
 					// log and skip
 					String msg = "Exception reading " + ELEMENT_NAME_PLACEHOLDER + " extension in bundle" + pluginId; //$NON-NLS-1$ //$NON-NLS-2$
 					HelpPlugin.logError(msg, e);
 				}
 			}
 		}
 		Collections.sort(placeholders);
 		// Read the preferences to find any ignored placeholders
 		String ignoredBundles = Platform.getPreferencesService().getString(HelpBasePlugin.PLUGIN_ID, IGNORE_MISSING_PLACEHOLDER_PREFERENCE, "", null); //$NON-NLS-1$
 		if (ignoredBundles.length() > 0) {
 			StringTokenizer tokenizer = new StringTokenizer(ignoredBundles, " ,"); //$NON-NLS-1$
 			while (tokenizer.hasMoreTokens()) {
 				bundlesToIgnore.add(tokenizer.nextToken());
 			}
 		}
 	}

 	/**
      * Called when a page cannot be found
 	 * @param path the path of the page that could not be loaded
 	 * @return a place holder page if defined, otherwise an error page
 	 */
 	public String getPageNotFoundPage(String path, boolean showPlaceholderPage) {
 		for (Iterator<Placeholder> iter = placeholders.iterator(); iter.hasNext(); ) {
 			Placeholder placeholder = iter.next();
 			if (path.startsWith(placeholder.path) && Platform.getBundle(placeholder.bundle) == null) {
 				if ( showPlaceholderPage) {
 				    return placeholder.placeholderPage;
 				} else {
 				    return "/org.eclipse.help.webapp/" + MISSING_TOPIC_PATH + path.substring(HELP_PROTOCOL.length()); //$NON-NLS-1$
 				}
 			}
 		}
 		return Platform.getPreferencesService().getString(HelpBasePlugin.PLUGIN_ID, "page_not_found", null, null); //$NON-NLS-1$
 	}

 	/**
 	 *
 	 * @return true if there is an unresolved place holder and this is not an infocenter
 	 */
 	public boolean isUnresolvedPlaceholders() {
 		if (BaseHelpSystem.getMode()==BaseHelpSystem.MODE_INFOCENTER) {
 			return false;
 		}
 		Placeholder[] unresolvedPlaceHolders = getUnresolvedPlaceholders();
 		return unresolvedPlaceHolders.length > 0;
 	}

 	/**
 	 * If any help is missing returns an appropriate page
 	 * @return null if no help is unavailable or an appropriate page if
 	 *  the plug-in that corresponds to a place holder is not available.
 	 *  The returned page will be in the format /plug-in/path.
 	 */
 	public String getHelpMissingPage(boolean isHelpView) {
 		Placeholder[] unresolvedPlaceHolders = getUnresolvedPlaceholders();
 		if (unresolvedPlaceHolders.length == 0) {
 		    	return null;
 		} else {
 			    String suffix = isHelpView ? MISSING_BOOKS_HELP_VIEW_HREF : MISSING_BOOKS_HREF;
 		    	return "/org.eclipse.help.webapp" + '/'+ suffix; //$NON-NLS-1$
 		}
 	}

 	/**
 	 * Get the page to be shown when some remote help is known to be unavailable
 	 */
 	public String getRemoteHelpUnavailablePage(boolean isHelpView) {
 		if ( BaseHelpSystem.getMode()!=BaseHelpSystem.MODE_INFOCENTER ) {
 		    String suffix = isHelpView ? REMOTE_STATUS_HELP_VIEW_HREF : REMOTE_STATUS_HREF;
 			return "/org.eclipse.help.webapp/" + suffix; //$NON-NLS-1$
 		}
 		return null;
 	}

 	public Placeholder[] getUnresolvedPlaceholders() {
 		List<Placeholder> unresolved;
 		unresolved = new ArrayList<>();
 		for (Iterator<Placeholder> iter = placeholders.iterator(); iter.hasNext(); ) {
 			Placeholder ph = iter.next();
 			String bundle = ph.bundle;
 			if (bundle != null && !bundlesToIgnore.contains(bundle) ) {
 			    if (Platform.getBundle(bundle) == null ) {
 			    	unresolved.add(ph);
 			    }
 			}
 		}
 		return unresolved.toArray(new Placeholder[unresolved.size()]);
 	}

 	// Modifies the preferences to ignore any bundles that are currently unresolved placeholders
 	public void ignoreAllMissingPlaceholders() {
 		Placeholder[] unresolved = getUnresolvedPlaceholders();
 		String ignoredBundles = Platform.getPreferencesService().getString(HelpBasePlugin.PLUGIN_ID, IGNORE_MISSING_PLACEHOLDER_PREFERENCE, "", null); //$NON-NLS-1$
 		for ( int i = 0; i < unresolved.length; i++) {
 			String bundle = unresolved[i].bundle;
 			bundlesToIgnore.add(bundle);
 			if (ignoredBundles.length() > 0) {
 				ignoredBundles = ignoredBundles + ',';
 			}
 			ignoredBundles = ignoredBundles + bundle;

 		}
 		IScopeContext instanceScope = InstanceScope.INSTANCE;
 		IEclipsePreferences prefs = instanceScope.getNode(HelpBasePlugin.PLUGIN_ID);
 		prefs.put(IGNORE_MISSING_PLACEHOLDER_PREFERENCE, ignoredBundles);
 		try {
 			prefs.flush();
 		} catch (BackingStoreException e) {
 			HelpBasePlugin.logError("Cannot save preferences", e); //$NON-NLS-1$
 		}
 	}

 }
	/*******************************************************************************
	* Copyright (c) 2011, 2015 IBM Corporation and others.
	*
	* This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License 2.0
	* which accompanies this distribution, and is available at
	* https://www.eclipse.org/legal/epl-2.0/
	*
	* SPDX-License-Identifier: EPL-2.0
	*
	* Contributors:
	* IBM Corporation - initial API and implementation
	*******************************************************************************/

	package org.eclipse.help.internal.base;

	import java.util.ArrayList;
	import java.util.Collections;
	import java.util.HashSet;
	import java.util.Iterator;
	import java.util.List;
	import java.util.Set;
	import java.util.StringTokenizer;

	import org.eclipse.core.runtime.IConfigurationElement;
	import org.eclipse.core.runtime.IExtensionRegistry;
	import org.eclipse.core.runtime.Platform;
	import org.eclipse.core.runtime.preferences.IEclipsePreferences;
	import org.eclipse.core.runtime.preferences.IScopeContext;
	import org.eclipse.core.runtime.preferences.InstanceScope;
	import org.eclipse.help.internal.HelpPlugin;
	import org.osgi.service.prefs.BackingStoreException;

	/**
	* Handles unresolved toc place holders as well as situations where remote help
	* is unavailable
	*/

	public class MissingContentManager {

	private static final String HELP_PROTOCOL = "help:"; //$NON-NLS-1$
	private static final String EXTENSION_POINT_ID_TOC = HelpPlugin.PLUGIN_ID + ".toc"; //$NON-NLS-1$
	private static final String ELEMENT_NAME_PLACEHOLDER = "placeholder"; //$NON-NLS-1$
	private static final String ATTRIBUTE_NAME_PLUGIN = "plugin"; //$NON-NLS-1$
	private static final String ATTRIBUTE_NAME_PLACEHOLDER_PAGE = "placeholderPage"; //$NON-NLS-1$
	public static final String IGNORE_MISSING_PLACEHOLDER_PREFERENCE = "ignorePlaceholders"; //$NON-NLS-1$

	// Hrefs which are processed by org.eclipse.help.internal.webapp.StatusProducer
	public static final String REMOTE_STATUS_HREF = "NetworkHelpStatus.html"; //$NON-NLS-1$
	public static final String REMOTE_STATUS_HELP_VIEW_HREF = "NetworkHelpStatusHV.html"; //$NON-NLS-1$
	public static final String MISSING_TOPIC_HREF = "MissingTopicStatus.html"; //$NON-NLS-1$
	public static final String MISSING_TOPIC_PATH = "missingTopic/"; //$NON-NLS-1$
	public static final String MISSING_BOOKS_HREF = "MissingBooks.html"; //$NON-NLS-1$
	public static final String MISSING_BOOKS_HELP_VIEW_HREF = "MissingBooksHV.html"; //$NON-NLS-1$

	/*
	* A place holder defines a page to be shown when a documentation page
	* which matches the specified path not installed
	*/
	public static class Placeholder implements Comparable<Placeholder> {
	public String path;
	public String bundle;
	public String placeholderPage;

	public Placeholder(String path, String bundle, String placeholderPage) {
	this.path = path;
	this.bundle = bundle;
	this.placeholderPage = placeholderPage;
	}

	@Override
	public int compareTo(Placeholder o) {
	return o.path.compareTo(path);
	}
	}

	private static MissingContentManager instance;
	private List<Placeholder> placeholders;
	private Set<String> bundlesToIgnore; // A set of bundles the user does not want to see reference to

	public static MissingContentManager getInstance() {
	if ( instance == null ) {
	instance = new MissingContentManager();
	}
	return instance;
	}

	/*
	* Read the extension registry
	*/
	private MissingContentManager() {
	IExtensionRegistry registry = Platform.getExtensionRegistry();
	placeholders = new ArrayList<>();
	bundlesToIgnore = new HashSet<>();
	if ( BaseHelpSystem.getMode() == BaseHelpSystem.MODE_INFOCENTER ) {
	return; // Placeholders are not shown for infocenters
	}
	// Read the placeholders from the extension registry
	IConfigurationElement[] elements = registry
	.getConfigurationElementsFor(EXTENSION_POINT_ID_TOC);
	for (int i = 0; i < elements.length; ++i) {
	IConfigurationElement elem = elements[i];
	String pluginId = elem.getContributor().getName();
	if (elem.getName().equals(ELEMENT_NAME_PLACEHOLDER)) {
	try {
	String plugin = elem.getAttribute(ATTRIBUTE_NAME_PLUGIN);
	String path = HELP_PROTOCOL + plugin + '/';
	String placeholder = elem
	.getAttribute(ATTRIBUTE_NAME_PLACEHOLDER_PAGE);
	placeholders.add(new Placeholder(path, plugin, placeholder));
	} catch (Exception e) {
	// log and skip
	String msg = "Exception reading " + ELEMENT_NAME_PLACEHOLDER + " extension in bundle" + pluginId; //$NON-NLS-1$ //$NON-NLS-2$
	HelpPlugin.logError(msg, e);
	}
	}
	}
	Collections.sort(placeholders);
	// Read the preferences to find any ignored placeholders
	String ignoredBundles = Platform.getPreferencesService().getString(HelpBasePlugin.PLUGIN_ID, IGNORE_MISSING_PLACEHOLDER_PREFERENCE, "", null); //$NON-NLS-1$
	if (ignoredBundles.length() > 0) {
	StringTokenizer tokenizer = new StringTokenizer(ignoredBundles, " ,"); //$NON-NLS-1$
	while (tokenizer.hasMoreTokens()) {
	bundlesToIgnore.add(tokenizer.nextToken());
	}
	}
	}

	/**
	* Called when a page cannot be found
	* @param path the path of the page that could not be loaded
	* @return a place holder page if defined, otherwise an error page
	*/
	public String getPageNotFoundPage(String path, boolean showPlaceholderPage) {
	for (Iterator<Placeholder> iter = placeholders.iterator(); iter.hasNext(); ) {
	Placeholder placeholder = iter.next();
	if (path.startsWith(placeholder.path) && Platform.getBundle(placeholder.bundle) == null) {
	if ( showPlaceholderPage) {
	return placeholder.placeholderPage;
	} else {
	return "/org.eclipse.help.webapp/" + MISSING_TOPIC_PATH + path.substring(HELP_PROTOCOL.length()); //$NON-NLS-1$
	}
	}
	}
	return Platform.getPreferencesService().getString(HelpBasePlugin.PLUGIN_ID, "page_not_found", null, null); //$NON-NLS-1$
	}

	/**
	*
	* @return true if there is an unresolved place holder and this is not an infocenter
	*/
	public boolean isUnresolvedPlaceholders() {
	if (BaseHelpSystem.getMode()==BaseHelpSystem.MODE_INFOCENTER) {
	return false;
	}
	Placeholder[] unresolvedPlaceHolders = getUnresolvedPlaceholders();
	return unresolvedPlaceHolders.length > 0;
	}

	/**
	* If any help is missing returns an appropriate page
	* @return null if no help is unavailable or an appropriate page if
	* the plug-in that corresponds to a place holder is not available.
	* The returned page will be in the format /plug-in/path.
	*/
	public String getHelpMissingPage(boolean isHelpView) {
	Placeholder[] unresolvedPlaceHolders = getUnresolvedPlaceholders();
	if (unresolvedPlaceHolders.length == 0) {
	return null;
	} else {
	String suffix = isHelpView ? MISSING_BOOKS_HELP_VIEW_HREF : MISSING_BOOKS_HREF;
	return "/org.eclipse.help.webapp" + '/'+ suffix; //$NON-NLS-1$
	}
	}

	/**
	* Get the page to be shown when some remote help is known to be unavailable
	*/
	public String getRemoteHelpUnavailablePage(boolean isHelpView) {
	if ( BaseHelpSystem.getMode()!=BaseHelpSystem.MODE_INFOCENTER ) {
	String suffix = isHelpView ? REMOTE_STATUS_HELP_VIEW_HREF : REMOTE_STATUS_HREF;
	return "/org.eclipse.help.webapp/" + suffix; //$NON-NLS-1$
	}
	return null;
	}

	public Placeholder[] getUnresolvedPlaceholders() {
	List<Placeholder> unresolved;
	unresolved = new ArrayList<>();
	for (Iterator<Placeholder> iter = placeholders.iterator(); iter.hasNext(); ) {
	Placeholder ph = iter.next();
	String bundle = ph.bundle;
	if (bundle != null && !bundlesToIgnore.contains(bundle) ) {
	if (Platform.getBundle(bundle) == null ) {
	unresolved.add(ph);
	}
	}
	}
	return unresolved.toArray(new Placeholder[unresolved.size()]);
	}

	// Modifies the preferences to ignore any bundles that are currently unresolved placeholders
	public void ignoreAllMissingPlaceholders() {
	Placeholder[] unresolved = getUnresolvedPlaceholders();
	String ignoredBundles = Platform.getPreferencesService().getString(HelpBasePlugin.PLUGIN_ID, IGNORE_MISSING_PLACEHOLDER_PREFERENCE, "", null); //$NON-NLS-1$
	for ( int i = 0; i < unresolved.length; i++) {
	String bundle = unresolved[i].bundle;
	bundlesToIgnore.add(bundle);
	if (ignoredBundles.length() > 0) {
	ignoredBundles = ignoredBundles + ',';
	}
	ignoredBundles = ignoredBundles + bundle;

	}
	IScopeContext instanceScope = InstanceScope.INSTANCE;
	IEclipsePreferences prefs = instanceScope.getNode(HelpBasePlugin.PLUGIN_ID);
	prefs.put(IGNORE_MISSING_PLACEHOLDER_PREFERENCE, ignoredBundles);
	try {
	prefs.flush();
	} catch (BackingStoreException e) {
	HelpBasePlugin.logError("Cannot save preferences", e); //$NON-NLS-1$
	}
	}

	}