Java tutorial
/** * Warlock, the open-source cross-platform game client * * Copyright 2008, Warlock LLC, and individual contributors as indicated * by the @authors tag. * * This is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This software is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this software; if not, write to the Free * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA, or see the FSF site: http://www.fsf.org. */ package cc.warlock.core.configuration; import java.io.File; import java.io.FileOutputStream; import java.io.IOException; import java.io.UnsupportedEncodingException; import java.util.ArrayList; import java.util.HashMap; import java.util.Iterator; import java.util.List; import java.util.Map; import org.dom4j.Document; import org.dom4j.DocumentException; import org.dom4j.DocumentHelper; import org.dom4j.Element; import org.dom4j.io.OutputFormat; import org.dom4j.io.SAXReader; import org.dom4j.io.XMLWriter; public class WarlockConfiguration { protected File configFile; protected Document document; protected Element warlockConfigElement; protected ArrayList<IConfigurationProvider> providers = new ArrayList<IConfigurationProvider>(); protected ArrayList<Element> unhandledElements = new ArrayList<Element>(); protected HashMap<Element, IConfigurationProvider> elementProviders = new HashMap<Element, IConfigurationProvider>(); protected static HashMap<String, WarlockConfiguration> configurations = new HashMap<String, WarlockConfiguration>(); public static WarlockConfiguration getWarlockConfiguration(String configFilename) { WarlockConfiguration config = configurations.get(configFilename); if (config == null) { config = new WarlockConfiguration(configFilename); configurations.put(configFilename, config); } return config; } public static WarlockConfiguration getMainConfiguration() { return getWarlockConfiguration(ConfigurationUtil.MAIN_CONFIGURATION_FILE); } public static void saveAll() { for (WarlockConfiguration config : configurations.values()) { config.save(); } } protected WarlockConfiguration(String filename) { configFile = ConfigurationUtil.getConfigurationFile(filename, true); loadXML(); } protected void loadXML() { if (configFile.length() == 0) return; try { SAXReader reader = new SAXReader(); document = reader.read(configFile); warlockConfigElement = document.getRootElement(); for (Element element : (List<Element>) warlockConfigElement.elements()) { unhandledElements.add(element); } } catch (DocumentException e) { // TODO Auto-generated catch block e.printStackTrace(); } } /** * Add Configuration Provider * * This adds the configuration provider and looks up the unhandled elements to see if any match it. * * @param provider */ public void addConfigurationProvider(IConfigurationProvider provider) { if (!providers.contains(provider)) { providers.add(provider); for (Iterator<Element> iter = unhandledElements.iterator(); iter.hasNext();) { Element element = iter.next(); if (provider.supportsElement(element)) { provider.parseElement(element); elementProviders.put(element, provider); iter.remove(); } } } } /** * Remove Configuration Provider * * This removes a configuration provider and grabs the element set, and adds it to the unhandled set. * * @param provider */ public void removeConfigurationProvider(IConfigurationProvider provider) { if (providers.remove(provider)) { if (elementProviders.containsValue(provider)) { // Grab elements and put them into unhandled (so they get saved) List<Element> elements = provider.getTopLevelElements(); for (Element element : elements) { unhandledElements.add(element); } // Remove Provider from our list of providers. for (Iterator<Map.Entry<Element, IConfigurationProvider>> iter = elementProviders.entrySet() .iterator(); iter.hasNext();) { Map.Entry<Element, IConfigurationProvider> entry = iter.next(); if (entry.getValue().equals(provider)) iter.remove(); } } } } /** * Delete Configuration Provider and Associated Elements * * This removes the element associated with with the provider as well as removing the listener on it. * * @param provider */ public void deleteConfigurationProvider(IConfigurationProvider provider) { if (providers.remove(provider)) { if (elementProviders.containsValue(provider)) { for (Iterator<Map.Entry<Element, IConfigurationProvider>> iter = elementProviders.entrySet() .iterator(); iter.hasNext();) { Map.Entry<Element, IConfigurationProvider> entry = iter.next(); if (entry.getValue().equals(provider)) iter.remove(); } } } } public void save() { Document document = DocumentHelper.createDocument(); Element warlockConfig = DocumentHelper.createElement("warlock-config"); document.setRootElement(warlockConfig); for (IConfigurationProvider provider : providers) { List<Element> elements = provider.getTopLevelElements(); for (Element element : elements) { warlockConfig.add(element); } } for (Element unhandled : unhandledElements) { // Make sure to resave unhandled elements, just in case the corresponding handler wasn't instantiated warlockConfig.add(unhandled.createCopy()); } try { if (configFile.exists()) { File backupFile = new File(configFile.getPath() + ".bak"); if (backupFile.exists()) backupFile.renameTo(new File(backupFile.getPath() + ".1")); configFile.renameTo(backupFile); } OutputFormat format = OutputFormat.createPrettyPrint(); FileOutputStream stream = new FileOutputStream(configFile); XMLWriter writer = new XMLWriter(stream, format); writer.write(document); stream.close(); } catch (UnsupportedEncodingException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } }