| /******************************************************************************* |
| * Copyright (c) 2006, 2008 Wind River Systems, IBM Corporation 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: |
| * Markus Schorn - initial API and implementation |
| *******************************************************************************/ |
| |
| package org.eclipse.search.internal.core.text; |
| |
| import java.util.ArrayList; |
| |
| import org.eclipse.core.runtime.IConfigurationElement; |
| import org.eclipse.core.runtime.Platform; |
| |
| import org.eclipse.jface.preference.IPreferenceStore; |
| import org.eclipse.jface.util.SafeRunnable; |
| |
| import org.eclipse.search.core.text.TextSearchEngine; |
| import org.eclipse.search.internal.ui.SearchMessages; |
| import org.eclipse.search.internal.ui.SearchPlugin; |
| import org.eclipse.search.internal.ui.SearchPreferencePage; |
| |
| |
| public class TextSearchEngineRegistry { |
| |
| private static final String EXTENSION_POINT_ID= "org.eclipse.search.textSearchEngine"; //$NON-NLS-1$ |
| private static final String ENGINE_NODE_NAME= "textSearchEngine"; //$NON-NLS-1$ |
| private static final String ATTRIB_ID= "id"; //$NON-NLS-1$ |
| private static final String ATTRIB_LABEL= "label"; //$NON-NLS-1$ |
| private static final String ATTRIB_CLASS= "class"; //$NON-NLS-1$ |
| |
| private TextSearchEngine fPreferredEngine; |
| private String fPreferredEngineId; |
| |
| public TextSearchEngineRegistry() { |
| fPreferredEngineId= null; // only null when not initialized |
| fPreferredEngine= null; |
| } |
| |
| public TextSearchEngine getPreferred() { |
| String preferredId= getPreferredEngineID(); |
| if (!preferredId.equals(fPreferredEngineId)) { |
| updateEngine(preferredId); |
| } |
| return fPreferredEngine; |
| } |
| |
| private void updateEngine(String preferredId) { |
| if (preferredId.length() != 0) { // empty string: default engine |
| TextSearchEngine engine= createFromExtension(preferredId); |
| if (engine != null) { |
| fPreferredEngineId= preferredId; |
| fPreferredEngine= engine; |
| return; |
| } |
| // creation failed, clear preference |
| setPreferredEngineID(""); // set to default //$NON-NLS-1$ |
| } |
| fPreferredEngineId= ""; //$NON-NLS-1$ |
| fPreferredEngine= TextSearchEngine.createDefault(); |
| } |
| |
| private String getPreferredEngineID() { |
| IPreferenceStore prefs= SearchPlugin.getDefault().getPreferenceStore(); |
| String preferedEngine= prefs.getString(SearchPreferencePage.TEXT_SEARCH_ENGINE); |
| return preferedEngine; |
| } |
| |
| private void setPreferredEngineID(String id) { |
| IPreferenceStore prefs= SearchPlugin.getDefault().getPreferenceStore(); |
| prefs.setValue(SearchPreferencePage.TEXT_SEARCH_ENGINE, id); |
| } |
| |
| private TextSearchEngine createFromExtension(final String id) { |
| final TextSearchEngine[] res= new TextSearchEngine[] { null }; |
| |
| SafeRunnable safe= new SafeRunnable() { |
| @Override |
| public void run() throws Exception { |
| IConfigurationElement[] extensions= Platform.getExtensionRegistry().getConfigurationElementsFor(EXTENSION_POINT_ID); |
| for (int i= 0; i < extensions.length; i++) { |
| IConfigurationElement curr= extensions[i]; |
| if (ENGINE_NODE_NAME.equals(curr.getName()) && id.equals(curr.getAttribute(ATTRIB_ID))) { |
| res[0]= (TextSearchEngine) curr.createExecutableExtension(ATTRIB_CLASS); |
| return; |
| } |
| } |
| } |
| @Override |
| public void handleException(Throwable e) { |
| SearchPlugin.log(e); |
| } |
| }; |
| SafeRunnable.run(safe); |
| return res[0]; |
| } |
| |
| public String[][] getAvailableEngines() { |
| ArrayList<String[]> res= new ArrayList<>(); |
| res.add(new String[] { SearchMessages.TextSearchEngineRegistry_defaulttextsearch_label, "" }); //$NON-NLS-1$ |
| |
| IConfigurationElement[] extensions= Platform.getExtensionRegistry().getConfigurationElementsFor(EXTENSION_POINT_ID); |
| for (int i= 0; i < extensions.length; i++) { |
| IConfigurationElement engine= extensions[i]; |
| if (ENGINE_NODE_NAME.equals(engine.getName())) { |
| res.add(new String[] { engine.getAttribute(ATTRIB_LABEL), engine.getAttribute(ATTRIB_ID) }); |
| } |
| } |
| return res.toArray(new String[res.size()][]); |
| } |
| } |