Java tutorial
/* * Copyright (c) 2006-2011 Nuxeo SA (http://nuxeo.com/) 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: * bstefanescu * * $Id$ */ package org.eclipse.ecr.runtime.deploy; import java.io.File; import java.io.IOException; import java.net.URI; import java.net.URL; import java.util.HashMap; import java.util.Map; import org.nuxeo.common.collections.ListenerList; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.eclipse.ecr.runtime.model.RuntimeContext; /** * @author <a href="mailto:bs@nuxeo.com">Bogdan Stefanescu</a> */ public class ConfigurationDeployer implements FileChangeListener { private static final Log log = LogFactory.getLog(ConfigurationDeployer.class); protected final Map<String, Entry> urls; protected final FileChangeNotifier notifier; protected final ListenerList listeners = new ListenerList(); public ConfigurationDeployer() { this(null); } public ConfigurationDeployer(FileChangeNotifier notifier) { this.notifier = notifier; urls = new HashMap<String, Entry>(); if (notifier != null) { notifier.addListener(this); } } public void deploy(RuntimeContext ctx, URL url, boolean trackChanges) throws Exception { File watchFile = null; if (trackChanges) { try { String str = url.toExternalForm(); if (str.startsWith("file:")) { watchFile = new File(url.toURI()); } else if (str.startsWith("jar:file:")) { int p = str.lastIndexOf('!'); if (p > -1) { str = str.substring(4, p); } else { str = str.substring(4); } watchFile = new File(new URI(str)); } } catch (Exception e) { log.error(e); watchFile = null; } } _deploy(ctx, url, watchFile, trackChanges); } public void undeploy(URL url) throws Exception { Entry entry = urls.remove(url.toExternalForm()); if (entry != null) { _undeploy(entry); } } public synchronized void _undeploy(Entry entry) throws Exception { try { entry.ctx.undeploy(entry.url); } finally { if (notifier != null && entry.watchFile != null) { notifier.unwatch(entry.url.toExternalForm(), entry.watchFile); } } } public void deploy(RuntimeContext ctx, File file, boolean trackChanges) throws Exception { _deploy(ctx, file.getCanonicalFile().toURI().toURL(), file, trackChanges); } public void undeploy(File file) throws Exception { undeploy(file.getCanonicalFile().toURI().toURL()); } protected synchronized void _deploy(RuntimeContext ctx, URL url, File watchFile, boolean trackChanges) throws Exception { String id = url.toExternalForm(); Entry entry = new Entry(ctx, url, watchFile); ctx.deploy(url); urls.put(id, entry); if (trackChanges && notifier != null && watchFile != null) { notifier.watch(id, watchFile); } } @Override public void fileChanged(FileChangeNotifier.FileEntry entry, long now) throws Exception { Entry e = urls.get(entry.id); if (e != null) { try { e.ctx.undeploy(e.url); e.ctx.deploy(e.url); } finally { fireConfigurationChanged(e); } } } public void addConfigurationChangedListener(ConfigurationChangedListener listener) { listeners.add(listener); } public void removeConfigurationChangedListener(ConfigurationChangedListener listener) { listeners.remove(listener); } public void fireConfigurationChanged(Entry entry) throws Exception { for (Object obj : listeners.getListenersCopy()) { ((ConfigurationChangedListener) obj).configurationChanged(entry); } } public static class Entry { final RuntimeContext ctx; final URL url; File watchFile; Entry(RuntimeContext ctx, URL config, File watchFile) throws IOException { url = config; this.ctx = ctx; if (watchFile != null) { this.watchFile = watchFile.getCanonicalFile(); } } public RuntimeContext getContext() { return ctx; } public File getWatchFile() { return watchFile; } public URL getUrl() { return url; } @Override public String toString() { return url.toExternalForm(); } } }