wikitext/ui/org.eclipse.mylyn.wikitext.ui/src/org/eclipse/mylyn/internal/wikitext/ui/registry/WikiTextExtensionPointReader.java - mylyn/org.eclipse.mylyn.docs - Git at Google

 /*******************************************************************************
  * Copyright (c) 2007, 2013 David Green and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v2.0
  * which accompanies this distribution, and is available at
  * https://www.eclipse.org/legal/epl-2.0/
  *
  * SPDX-License-Identifier: EPL-2.0
  *
  * Contributors:
  *     David Green - initial API and implementation
  *******************************************************************************/

 package org.eclipse.mylyn.internal.wikitext.ui.registry;

 import java.text.MessageFormat;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Map.Entry;
 import java.util.Set;
 import java.util.SortedMap;
 import java.util.TreeMap;

 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IConfigurationElement;
 import org.eclipse.core.runtime.IExtensionPoint;
 import org.eclipse.core.runtime.ILog;
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.Platform;
 import org.eclipse.core.runtime.Status;
 import org.eclipse.mylyn.internal.wikitext.ui.WikiTextUiPlugin;
 import org.eclipse.mylyn.wikitext.parser.markup.MarkupLanguage;
 import org.eclipse.mylyn.wikitext.validation.MarkupValidator;
 import org.eclipse.mylyn.wikitext.validation.ValidationRule;
 import org.eclipse.mylyn.wikitext.validation.ValidationRules;

 import com.google.common.collect.Sets;

 public class WikiTextExtensionPointReader {

 	private static final String EXTENSION_POINT_NAMESPACE = "org.eclipse.mylyn.wikitext.ui"; //$NON-NLS-1$

 	private static final String EXTENSION_MARKUP_LANGUAGE = "markupLanguage"; //$NON-NLS-1$

 	private static final String EXTENSION_VALIDATION_RULES = "markupValidationRule"; //$NON-NLS-1$

 	private static Object instanceLock = new Object();

 	private static WikiTextExtensionPointReader instance;

 	private SortedMap<String, Class<? extends MarkupLanguage>> languageByName;

 	private Map<String, Class<? extends MarkupLanguage>> languageByFileExtension;

 	private Map<Class<? extends MarkupLanguage>, String> languageNameByLanguage;

 	private Map<String, String> languageExtensionByLanguage;

 	private Map<String, ValidationRules> validationRulesByLanguageName;

 	public static WikiTextExtensionPointReader instance() {
 		synchronized (instanceLock) {
 			if (instance == null) {
 				instance = new WikiTextExtensionPointReader();
 			}
 			return instance;
 		}
 	}

 	private WikiTextExtensionPointReader() {
 		// prevent instantiation
 	}

 	/**
 	 * Get a markup language by name.
 	 *
 	 * @param name
 	 *            the name of the markup language to retrieve
 	 * @return the markup language or null if there is no markup language known by the given name
 	 * @see #getMarkupLanguageNames()
 	 */
 	public MarkupLanguage getMarkupLanguage(String name) {
 		if (languageByName == null) {
 			initializeMarkupLanguages();
 		}
 		Class<? extends MarkupLanguage> languageClass = languageByName.get(name);
 		if (languageClass == null) {
 			// if not found by name, attempt to lookup by class name.
 			for (Entry<String, Class<? extends MarkupLanguage>> entry : languageByName.entrySet()) {
 				Class<? extends MarkupLanguage> clazz = entry.getValue();
 				if (clazz.getName().equals(name)) {
 					languageClass = clazz;
 					name = entry.getKey();
 					break;
 				}
 			}
 		}
 		if (languageClass != null) {
 			return instantiateMarkupLanguage(name, languageClass);
 		}
 		return null;
 	}

 	private MarkupLanguage instantiateMarkupLanguage(String name, Class<? extends MarkupLanguage> languageClass) {
 		try {
 			MarkupLanguage language = languageClass.newInstance();
 			language.setName(name);
 			language.setExtendsLanguage(languageExtensionByLanguage.get(name));
 			configureFileExtensions(language);
 			return language;
 		} catch (Exception e) {
 			log(IStatus.ERROR, MessageFormat.format(Messages.getString("WikiTextExtensionPointReader.2"), name, //$NON-NLS-1$
 					languageClass.getName(), e.getMessage()), e);
 		}
 		return null;
 	}

 	private void configureFileExtensions(MarkupLanguage language) {
 		Set<String> fileExtensions = Sets.newHashSet();
 		for (Entry<String, Class<? extends MarkupLanguage>> entry : languageByFileExtension.entrySet()) {
 			if (entry.getValue() == language.getClass()) {
 				fileExtensions.add(entry.getKey());
 			}
 		}
 		if (!fileExtensions.isEmpty()) {
 			language.setFileExtensions(fileExtensions);
 		}
 	}

 	/**
 	 * Get a markup language name for a file. A markup language is selected based on the registered languages and their
 	 * expected file extensions.
 	 *
 	 * @param name
 	 *            the name of the file for which a markup language is desired
 	 * @return the markup language name, or null if no markup language is registered for the specified file name
 	 * @see #getMarkupLanguageForFilename(String)
 	 */
 	public String getMarkupLanguageNameForFilename(String name) {
 		if (languageByFileExtension == null) {
 			initializeMarkupLanguages();
 		}
 		int lastIndexOfDot = name.lastIndexOf('.');
 		String extension = lastIndexOfDot == -1 ? name : name.substring(lastIndexOfDot + 1);
 		extension = extension.toLowerCase();
 		Class<? extends MarkupLanguage> languageClass = languageByFileExtension.get(extension);
 		if (languageClass != null) {
 			return languageNameByLanguage.get(languageClass);
 		}
 		return null;
 	}

 	/**
 	 * Get the file extensions that are registered for markup languages. File extensions are specified without the
 	 * leading dot.
 	 */
 	public Set<String> getMarkupFileExtensions() {
 		if (languageByFileExtension == null) {
 			initializeMarkupLanguages();
 		}
 		return Collections.unmodifiableSet(languageByFileExtension.keySet());
 	}

 	/**
 	 * Get a markup language for a file. A markup language is selected based on the registered languages and their
 	 * expected file extensions.
 	 *
 	 * @param name
 	 *            the name of the file for which a markup language is desired
 	 * @return the markup language, or null if no markup language is registered for the specified file name
 	 * @see #getMarkupLanguageForFilename(String)
 	 */
 	public MarkupLanguage getMarkupLanguageForFilename(String name) {
 		if (languageByFileExtension == null) {
 			initializeMarkupLanguages();
 		}
 		int lastIndexOfDot = name.lastIndexOf('.');
 		String extension = lastIndexOfDot == -1 ? name : name.substring(lastIndexOfDot + 1);
 		Class<? extends MarkupLanguage> languageClass = languageByFileExtension.get(extension);
 		if (languageClass != null) {
 			String languageName = null;
 			for (Map.Entry<String, Class<? extends MarkupLanguage>> ent : languageByName.entrySet()) {
 				if (ent.getValue() == languageClass) {
 					languageName = ent.getKey();
 					break;
 				}
 			}
 			return instantiateMarkupLanguage(languageName, languageClass);
 		}
 		return null;
 	}

 	/**
 	 * Get the names of all known markup languages
 	 *
 	 * @see #getMarkupLanguage(String)
 	 */
 	public Set<String> getMarkupLanguageNames() {
 		if (languageByName == null) {
 			initializeMarkupLanguages();
 		}
 		return languageByName.keySet();
 	}

 	/**
 	 * Get a markup validator by language name.
 	 *
 	 * @param name
 	 *            the name of the markup language for which a validator is desired
 	 * @return the markup validator
 	 * @see #getMarkupLanguageNames()
 	 */
 	public MarkupValidator getMarkupValidator(String name) {
 		MarkupValidator markupValidator = new MarkupValidator();

 		if (validationRulesByLanguageName == null) {
 			initializeValidationRules();
 		}
 		ValidationRules rules = validationRulesByLanguageName.get(name);
 		if (rules != null) {
 			markupValidator.getRules().addAll(rules.getRules());
 		}

 		return markupValidator;
 	}

 	private void initializeValidationRules() {
 		initializeMarkupLanguages();
 		synchronized (this) {
 			if (validationRulesByLanguageName == null) {
 				Map<String, ValidationRules> validationRulesByLanguageName = new HashMap<>();

 				IExtensionPoint extensionPoint = Platform.getExtensionRegistry()
 						.getExtensionPoint(getExtensionPointNamespace(), EXTENSION_VALIDATION_RULES);
 				if (extensionPoint != null) {
 					IConfigurationElement[] configurationElements = extensionPoint.getConfigurationElements();
 					for (IConfigurationElement element : configurationElements) {
 						try {
 							String markupLanguage = element.getAttribute("markupLanguage"); //$NON-NLS-1$
 							if (markupLanguage == null || markupLanguage.length() == 0) {
 								throw new Exception(Messages.getString("WikiTextExtensionPointReader.4")); //$NON-NLS-1$
 							}
 							if (!languageByName.containsKey(markupLanguage)) {
 								throw new Exception(MessageFormat
 										.format(Messages.getString("WikiTextExtensionPointReader.5"), languageByName)); //$NON-NLS-1$
 							}
 							Object extension;
 							try {
 								extension = element.createExecutableExtension("class"); //$NON-NLS-1$
 							} catch (CoreException e) {
 								getLog().log(e.getStatus());
 								continue;
 							}
 							if (!(extension instanceof ValidationRule)) {
 								throw new Exception(MessageFormat.format(
 										Messages.getString("WikiTextExtensionPointReader.7"), extension.getClass() //$NON-NLS-1$
 												.getName()));
 							}
 							ValidationRules rules = validationRulesByLanguageName.get(markupLanguage);
 							if (rules == null) {
 								rules = new ValidationRules();
 								validationRulesByLanguageName.put(markupLanguage, rules);
 							}
 							rules.addValidationRule((ValidationRule) extension);
 						} catch (Exception e) {
 							log(IStatus.ERROR,
 									MessageFormat.format(Messages.getString("WikiTextExtensionPointReader.8"), //$NON-NLS-1$
 											element.getDeclaringExtension().getContributor().getName(),
 											EXTENSION_VALIDATION_RULES, e.getMessage()),
 									e);
 						}
 					}
 				}

 				// now that we have the basic validation rules, check for language extensions and connect the hierarchy

 				// first ensure that all language names have templates defined
 				Set<String> languageNames = getMarkupLanguageNames();
 				for (String languageName : languageNames) {
 					ValidationRules rules = validationRulesByLanguageName.get(languageName);
 					if (rules == null) {
 						rules = new ValidationRules();
 						validationRulesByLanguageName.put(languageName, rules);
 					}
 				}
 				// next connect the hierarchy
 				for (String languageName : languageNames) {
 					MarkupLanguage markupLanguage = getMarkupLanguage(languageName);
 					if (markupLanguage != null && markupLanguage.getExtendsLanguage() != null) {
 						ValidationRules languageRules = validationRulesByLanguageName.get(languageName);
 						ValidationRules parentLanguageRules = validationRulesByLanguageName
 								.get(markupLanguage.getExtendsLanguage());

 						languageRules.setParent(parentLanguageRules);
 					}
 				}

 				this.validationRulesByLanguageName = validationRulesByLanguageName;
 			}
 		}
 	}

 	private void initializeMarkupLanguages() {
 		synchronized (this) {
 			if (this.languageByName == null) {
 				SortedMap<String, Class<? extends MarkupLanguage>> markupLanguageByName = new TreeMap<>();
 				Map<String, Class<? extends MarkupLanguage>> languageByFileExtension = new HashMap<>();
 				Map<String, String> languageExtensionByLanguage = new HashMap<>();
 				Map<Class<? extends MarkupLanguage>, String> languageNameByLanguage = new HashMap<>();

 				IExtensionPoint extensionPoint = Platform.getExtensionRegistry()
 						.getExtensionPoint(getExtensionPointNamespace(), EXTENSION_MARKUP_LANGUAGE);
 				if (extensionPoint != null) {
 					IConfigurationElement[] configurationElements = extensionPoint.getConfigurationElements();
 					for (IConfigurationElement element : configurationElements) {
 						String name = element.getAttribute("name"); //$NON-NLS-1$
 						if (name == null || name.length() == 0) {
 							log(IStatus.ERROR,
 									MessageFormat.format(
 											EXTENSION_MARKUP_LANGUAGE
 													+ Messages.getString("WikiTextExtensionPointReader.10"), //$NON-NLS-1$
 											element.getDeclaringExtension().getContributor().getName()));
 							continue;
 						}
 						String extendsLanguage = element.getAttribute("extends"); //$NON-NLS-1$
 						Object markupLanguage;
 						try {
 							markupLanguage = element.createExecutableExtension("class"); //$NON-NLS-1$
 						} catch (CoreException e) {
 							getLog().log(e.getStatus());
 							continue;
 						}
 						if (!(markupLanguage instanceof MarkupLanguage)) {
 							log(IStatus.ERROR,
 									MessageFormat.format(Messages.getString("WikiTextExtensionPointReader.13"), //$NON-NLS-1$
 											markupLanguage.getClass().getName()));
 							continue;
 						}
 						MarkupLanguage d = (MarkupLanguage) markupLanguage;
 						{
 							Class<? extends MarkupLanguage> previous = markupLanguageByName.put(name, d.getClass());
 							if (previous != null) {
 								log(IStatus.ERROR, MessageFormat.format(
 										EXTENSION_MARKUP_LANGUAGE
 												+ Messages.getString("WikiTextExtensionPointReader.14"), //$NON-NLS-1$
 										name, element.getDeclaringExtension().getContributor().getName(), name));
 								markupLanguageByName.put(name, previous);
 								continue;
 							} else {
 								languageNameByLanguage.put(d.getClass(), name);
 							}
 						}
 						if (extendsLanguage != null) {
 							languageExtensionByLanguage.put(name, extendsLanguage);
 						}
 						String fileExtensions = element.getAttribute("fileExtensions"); //$NON-NLS-1$
 						if (fileExtensions != null) {
 							String[] parts = fileExtensions.split("\\s*,\\s*"); //$NON-NLS-1$
 							for (String part : parts) {
 								if (part.length() != 0) {
 									part = part.toLowerCase();
 									Class<? extends MarkupLanguage> previous = languageByFileExtension.put(part,
 											d.getClass());
 									if (previous != null) {
 										log(IStatus.ERROR, MessageFormat.format(
 												EXTENSION_MARKUP_LANGUAGE
 														+ Messages.getString("WikiTextExtensionPointReader.17"), //$NON-NLS-1$
 												part, element.getDeclaringExtension().getContributor().getName(),
 												part));
 										languageByFileExtension.put(part, previous);
 										continue;
 									}
 								}
 							}

 						}
 					}
 				}

 				this.languageByFileExtension = languageByFileExtension;
 				this.languageByName = markupLanguageByName;
 				this.languageExtensionByLanguage = languageExtensionByLanguage;
 				this.languageNameByLanguage = languageNameByLanguage;
 			}
 		}
 	}

 	private ILog getLog() {
 		return WikiTextUiPlugin.getDefault().getLog();
 	}

 	private void log(int severity, String message) {
 		log(severity, message, null);
 	}

 	private void log(int severity, String message, Throwable t) {
 		getLog().log(new Status(severity, WikiTextUiPlugin.getDefault().getPluginId(), message, t));
 	}

 	private String getExtensionPointNamespace() {
 		return EXTENSION_POINT_NAMESPACE;
 	}

 }
	/*******************************************************************************
	* Copyright (c) 2007, 2013 David Green and others.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License v2.0
	* which accompanies this distribution, and is available at
	* https://www.eclipse.org/legal/epl-2.0/
	*
	* SPDX-License-Identifier: EPL-2.0
	*
	* Contributors:
	* David Green - initial API and implementation
	*******************************************************************************/

	package org.eclipse.mylyn.internal.wikitext.ui.registry;

	import java.text.MessageFormat;
	import java.util.Collections;
	import java.util.HashMap;
	import java.util.Map;
	import java.util.Map.Entry;
	import java.util.Set;
	import java.util.SortedMap;
	import java.util.TreeMap;

	import org.eclipse.core.runtime.CoreException;
	import org.eclipse.core.runtime.IConfigurationElement;
	import org.eclipse.core.runtime.IExtensionPoint;
	import org.eclipse.core.runtime.ILog;
	import org.eclipse.core.runtime.IStatus;
	import org.eclipse.core.runtime.Platform;
	import org.eclipse.core.runtime.Status;
	import org.eclipse.mylyn.internal.wikitext.ui.WikiTextUiPlugin;
	import org.eclipse.mylyn.wikitext.parser.markup.MarkupLanguage;
	import org.eclipse.mylyn.wikitext.validation.MarkupValidator;
	import org.eclipse.mylyn.wikitext.validation.ValidationRule;
	import org.eclipse.mylyn.wikitext.validation.ValidationRules;

	import com.google.common.collect.Sets;

	public class WikiTextExtensionPointReader {

	private static final String EXTENSION_POINT_NAMESPACE = "org.eclipse.mylyn.wikitext.ui"; //$NON-NLS-1$

	private static final String EXTENSION_MARKUP_LANGUAGE = "markupLanguage"; //$NON-NLS-1$

	private static final String EXTENSION_VALIDATION_RULES = "markupValidationRule"; //$NON-NLS-1$

	private static Object instanceLock = new Object();

	private static WikiTextExtensionPointReader instance;

	private SortedMap<String, Class<? extends MarkupLanguage>> languageByName;

	private Map<String, Class<? extends MarkupLanguage>> languageByFileExtension;

	private Map<Class<? extends MarkupLanguage>, String> languageNameByLanguage;

	private Map<String, String> languageExtensionByLanguage;

	private Map<String, ValidationRules> validationRulesByLanguageName;

	public static WikiTextExtensionPointReader instance() {
	synchronized (instanceLock) {
	if (instance == null) {
	instance = new WikiTextExtensionPointReader();
	}
	return instance;
	}
	}

	private WikiTextExtensionPointReader() {
	// prevent instantiation
	}

	/**
	* Get a markup language by name.
	*
	* @param name
	* the name of the markup language to retrieve
	* @return the markup language or null if there is no markup language known by the given name
	* @see #getMarkupLanguageNames()
	*/
	public MarkupLanguage getMarkupLanguage(String name) {
	if (languageByName == null) {
	initializeMarkupLanguages();
	}
	Class<? extends MarkupLanguage> languageClass = languageByName.get(name);
	if (languageClass == null) {
	// if not found by name, attempt to lookup by class name.
	for (Entry<String, Class<? extends MarkupLanguage>> entry : languageByName.entrySet()) {
	Class<? extends MarkupLanguage> clazz = entry.getValue();
	if (clazz.getName().equals(name)) {
	languageClass = clazz;
	name = entry.getKey();
	break;
	}
	}
	}
	if (languageClass != null) {
	return instantiateMarkupLanguage(name, languageClass);
	}
	return null;
	}

	private MarkupLanguage instantiateMarkupLanguage(String name, Class<? extends MarkupLanguage> languageClass) {
	try {
	MarkupLanguage language = languageClass.newInstance();
	language.setName(name);
	language.setExtendsLanguage(languageExtensionByLanguage.get(name));
	configureFileExtensions(language);
	return language;
	} catch (Exception e) {
	log(IStatus.ERROR, MessageFormat.format(Messages.getString("WikiTextExtensionPointReader.2"), name, //$NON-NLS-1$
	languageClass.getName(), e.getMessage()), e);
	}
	return null;
	}

	private void configureFileExtensions(MarkupLanguage language) {
	Set<String> fileExtensions = Sets.newHashSet();
	for (Entry<String, Class<? extends MarkupLanguage>> entry : languageByFileExtension.entrySet()) {
	if (entry.getValue() == language.getClass()) {
	fileExtensions.add(entry.getKey());
	}
	}
	if (!fileExtensions.isEmpty()) {
	language.setFileExtensions(fileExtensions);
	}
	}

	/**
	* Get a markup language name for a file. A markup language is selected based on the registered languages and their
	* expected file extensions.
	*
	* @param name
	* the name of the file for which a markup language is desired
	* @return the markup language name, or null if no markup language is registered for the specified file name
	* @see #getMarkupLanguageForFilename(String)
	*/
	public String getMarkupLanguageNameForFilename(String name) {
	if (languageByFileExtension == null) {
	initializeMarkupLanguages();
	}
	int lastIndexOfDot = name.lastIndexOf('.');
	String extension = lastIndexOfDot == -1 ? name : name.substring(lastIndexOfDot + 1);
	extension = extension.toLowerCase();
	Class<? extends MarkupLanguage> languageClass = languageByFileExtension.get(extension);
	if (languageClass != null) {
	return languageNameByLanguage.get(languageClass);
	}
	return null;
	}

	/**
	* Get the file extensions that are registered for markup languages. File extensions are specified without the
	* leading dot.
	*/
	public Set<String> getMarkupFileExtensions() {
	if (languageByFileExtension == null) {
	initializeMarkupLanguages();
	}
	return Collections.unmodifiableSet(languageByFileExtension.keySet());
	}

	/**
	* Get a markup language for a file. A markup language is selected based on the registered languages and their
	* expected file extensions.
	*
	* @param name
	* the name of the file for which a markup language is desired
	* @return the markup language, or null if no markup language is registered for the specified file name
	* @see #getMarkupLanguageForFilename(String)
	*/
	public MarkupLanguage getMarkupLanguageForFilename(String name) {
	if (languageByFileExtension == null) {
	initializeMarkupLanguages();
	}
	int lastIndexOfDot = name.lastIndexOf('.');
	String extension = lastIndexOfDot == -1 ? name : name.substring(lastIndexOfDot + 1);
	Class<? extends MarkupLanguage> languageClass = languageByFileExtension.get(extension);
	if (languageClass != null) {
	String languageName = null;
	for (Map.Entry<String, Class<? extends MarkupLanguage>> ent : languageByName.entrySet()) {
	if (ent.getValue() == languageClass) {
	languageName = ent.getKey();
	break;
	}
	}
	return instantiateMarkupLanguage(languageName, languageClass);
	}
	return null;
	}

	/**
	* Get the names of all known markup languages
	*
	* @see #getMarkupLanguage(String)
	*/
	public Set<String> getMarkupLanguageNames() {
	if (languageByName == null) {
	initializeMarkupLanguages();
	}
	return languageByName.keySet();
	}

	/**
	* Get a markup validator by language name.
	*
	* @param name
	* the name of the markup language for which a validator is desired
	* @return the markup validator
	* @see #getMarkupLanguageNames()
	*/
	public MarkupValidator getMarkupValidator(String name) {
	MarkupValidator markupValidator = new MarkupValidator();

	if (validationRulesByLanguageName == null) {
	initializeValidationRules();
	}
	ValidationRules rules = validationRulesByLanguageName.get(name);
	if (rules != null) {
	markupValidator.getRules().addAll(rules.getRules());
	}

	return markupValidator;
	}

	private void initializeValidationRules() {
	initializeMarkupLanguages();
	synchronized (this) {
	if (validationRulesByLanguageName == null) {
	Map<String, ValidationRules> validationRulesByLanguageName = new HashMap<>();

	IExtensionPoint extensionPoint = Platform.getExtensionRegistry()
	.getExtensionPoint(getExtensionPointNamespace(), EXTENSION_VALIDATION_RULES);
	if (extensionPoint != null) {
	IConfigurationElement[] configurationElements = extensionPoint.getConfigurationElements();
	for (IConfigurationElement element : configurationElements) {
	try {
	String markupLanguage = element.getAttribute("markupLanguage"); //$NON-NLS-1$
	if (markupLanguage == null \|\| markupLanguage.length() == 0) {
	throw new Exception(Messages.getString("WikiTextExtensionPointReader.4")); //$NON-NLS-1$
	}
	if (!languageByName.containsKey(markupLanguage)) {
	throw new Exception(MessageFormat
	.format(Messages.getString("WikiTextExtensionPointReader.5"), languageByName)); //$NON-NLS-1$
	}
	Object extension;
	try {
	extension = element.createExecutableExtension("class"); //$NON-NLS-1$
	} catch (CoreException e) {
	getLog().log(e.getStatus());
	continue;
	}
	if (!(extension instanceof ValidationRule)) {
	throw new Exception(MessageFormat.format(
	Messages.getString("WikiTextExtensionPointReader.7"), extension.getClass() //$NON-NLS-1$
	.getName()));
	}
	ValidationRules rules = validationRulesByLanguageName.get(markupLanguage);
	if (rules == null) {
	rules = new ValidationRules();
	validationRulesByLanguageName.put(markupLanguage, rules);
	}
	rules.addValidationRule((ValidationRule) extension);
	} catch (Exception e) {
	log(IStatus.ERROR,
	MessageFormat.format(Messages.getString("WikiTextExtensionPointReader.8"), //$NON-NLS-1$
	element.getDeclaringExtension().getContributor().getName(),
	EXTENSION_VALIDATION_RULES, e.getMessage()),
	e);
	}
	}
	}

	// now that we have the basic validation rules, check for language extensions and connect the hierarchy

	// first ensure that all language names have templates defined
	Set<String> languageNames = getMarkupLanguageNames();
	for (String languageName : languageNames) {
	ValidationRules rules = validationRulesByLanguageName.get(languageName);
	if (rules == null) {
	rules = new ValidationRules();
	validationRulesByLanguageName.put(languageName, rules);
	}
	}
	// next connect the hierarchy
	for (String languageName : languageNames) {
	MarkupLanguage markupLanguage = getMarkupLanguage(languageName);
	if (markupLanguage != null && markupLanguage.getExtendsLanguage() != null) {
	ValidationRules languageRules = validationRulesByLanguageName.get(languageName);
	ValidationRules parentLanguageRules = validationRulesByLanguageName
	.get(markupLanguage.getExtendsLanguage());

	languageRules.setParent(parentLanguageRules);
	}
	}

	this.validationRulesByLanguageName = validationRulesByLanguageName;
	}
	}
	}

	private void initializeMarkupLanguages() {
	synchronized (this) {
	if (this.languageByName == null) {
	SortedMap<String, Class<? extends MarkupLanguage>> markupLanguageByName = new TreeMap<>();
	Map<String, Class<? extends MarkupLanguage>> languageByFileExtension = new HashMap<>();
	Map<String, String> languageExtensionByLanguage = new HashMap<>();
	Map<Class<? extends MarkupLanguage>, String> languageNameByLanguage = new HashMap<>();

	IExtensionPoint extensionPoint = Platform.getExtensionRegistry()
	.getExtensionPoint(getExtensionPointNamespace(), EXTENSION_MARKUP_LANGUAGE);
	if (extensionPoint != null) {
	IConfigurationElement[] configurationElements = extensionPoint.getConfigurationElements();
	for (IConfigurationElement element : configurationElements) {
	String name = element.getAttribute("name"); //$NON-NLS-1$
	if (name == null \|\| name.length() == 0) {
	log(IStatus.ERROR,
	MessageFormat.format(
	EXTENSION_MARKUP_LANGUAGE
	+ Messages.getString("WikiTextExtensionPointReader.10"), //$NON-NLS-1$
	element.getDeclaringExtension().getContributor().getName()));
	continue;
	}
	String extendsLanguage = element.getAttribute("extends"); //$NON-NLS-1$
	Object markupLanguage;
	try {
	markupLanguage = element.createExecutableExtension("class"); //$NON-NLS-1$
	} catch (CoreException e) {
	getLog().log(e.getStatus());
	continue;
	}
	if (!(markupLanguage instanceof MarkupLanguage)) {
	log(IStatus.ERROR,
	MessageFormat.format(Messages.getString("WikiTextExtensionPointReader.13"), //$NON-NLS-1$
	markupLanguage.getClass().getName()));
	continue;
	}
	MarkupLanguage d = (MarkupLanguage) markupLanguage;
	{
	Class<? extends MarkupLanguage> previous = markupLanguageByName.put(name, d.getClass());
	if (previous != null) {
	log(IStatus.ERROR, MessageFormat.format(
	EXTENSION_MARKUP_LANGUAGE
	+ Messages.getString("WikiTextExtensionPointReader.14"), //$NON-NLS-1$
	name, element.getDeclaringExtension().getContributor().getName(), name));
	markupLanguageByName.put(name, previous);
	continue;
	} else {
	languageNameByLanguage.put(d.getClass(), name);
	}
	}
	if (extendsLanguage != null) {
	languageExtensionByLanguage.put(name, extendsLanguage);
	}
	String fileExtensions = element.getAttribute("fileExtensions"); //$NON-NLS-1$
	if (fileExtensions != null) {
	String[] parts = fileExtensions.split("\\s,\\s"); //$NON-NLS-1$
	for (String part : parts) {
	if (part.length() != 0) {
	part = part.toLowerCase();
	Class<? extends MarkupLanguage> previous = languageByFileExtension.put(part,
	d.getClass());
	if (previous != null) {
	log(IStatus.ERROR, MessageFormat.format(
	EXTENSION_MARKUP_LANGUAGE
	+ Messages.getString("WikiTextExtensionPointReader.17"), //$NON-NLS-1$
	part, element.getDeclaringExtension().getContributor().getName(),
	part));
	languageByFileExtension.put(part, previous);
	continue;
	}
	}
	}

	}
	}
	}

	this.languageByFileExtension = languageByFileExtension;
	this.languageByName = markupLanguageByName;
	this.languageExtensionByLanguage = languageExtensionByLanguage;
	this.languageNameByLanguage = languageNameByLanguage;
	}
	}
	}

	private ILog getLog() {
	return WikiTextUiPlugin.getDefault().getLog();
	}

	private void log(int severity, String message) {
	log(severity, message, null);
	}

	private void log(int severity, String message, Throwable t) {
	getLog().log(new Status(severity, WikiTextUiPlugin.getDefault().getPluginId(), message, t));
	}

	private String getExtensionPointNamespace() {
	return EXTENSION_POINT_NAMESPACE;
	}

	}