Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.apache.cocoon.components.source.impl; import java.io.File; import java.io.IOException; import java.net.MalformedURLException; import java.net.URL; import java.util.Map; import java.util.Set; import javax.servlet.ServletContext; import org.apache.avalon.framework.context.ContextException; import org.apache.avalon.framework.context.Contextualizable; import org.apache.avalon.framework.service.ServiceException; import org.apache.avalon.framework.service.ServiceManager; import org.apache.avalon.framework.service.Serviceable; import org.apache.avalon.framework.thread.ThreadSafe; import org.apache.commons.lang.BooleanUtils; import org.apache.excalibur.source.Source; import org.apache.excalibur.source.SourceException; import org.apache.excalibur.source.SourceFactory; import org.apache.excalibur.source.SourceResolver; import org.apache.excalibur.source.SourceUtil; import org.apache.excalibur.source.TraversableSource; import org.apache.excalibur.source.URIAbsolutizer; import org.apache.cocoon.Constants; import org.apache.cocoon.environment.Context; import org.apache.cocoon.util.AbstractLogEnabled; /** * A factory for the context protocol using the context of the servlet api. * It builds the source by asking the environment context for the real URL * (see {@link org.apache.cocoon.environment.Context#getResource(String)}) * and then resolving this real URL. * * @version $Id: ContextSourceFactory.java 606174 2007-12-21 12:27:53Z vgritsenko $ */ public class ContextSourceFactory extends AbstractLogEnabled implements SourceFactory, Serviceable, Contextualizable, ThreadSafe, URIAbsolutizer { /** The ServiceManager */ protected ServiceManager manager; /** Http servlet context - if available */ protected ServletContext servletContext; /** * @see org.apache.avalon.framework.service.Serviceable#service(org.apache.avalon.framework.service.ServiceManager) */ public void service(ServiceManager manager) throws ServiceException { this.manager = manager; } /** * @see org.apache.avalon.framework.context.Contextualizable#contextualize(org.apache.avalon.framework.context.Context) */ public void contextualize(org.apache.avalon.framework.context.Context context) throws ContextException { this.servletContext = (Context) context.get(Constants.CONTEXT_ENVIRONMENT_CONTEXT); } /** * @see org.apache.excalibur.source.SourceFactory#getSource(java.lang.String, java.util.Map) */ public Source getSource(String location, Map parameters) throws IOException { if (getLogger().isDebugEnabled()) { getLogger().debug("Creating source object for " + location); } // Lookup resolver SourceResolver resolver = null; try { resolver = (SourceResolver) this.manager.lookup(SourceResolver.ROLE); // Remove the protocol and the first '/' final int pos = location.indexOf(":/"); final String scheme = location.substring(0, pos); final String path = location.substring(pos + 2); // fix for #24093, we don't give access to files outside the context: if (path.indexOf("../") != -1) { throw new MalformedURLException("Invalid path ('../' is not allowed) : " + path); } URL u; // Try to get a file first and fall back to a resource URL String actualPath = this.servletContext.getRealPath(path); if (actualPath != null) { u = new File(actualPath).toURL(); } else { u = this.servletContext.getResource(path); } if (u != null) { Source source = resolver.resolveURI(u.toExternalForm()); if (parameters != null && BooleanUtils.toBoolean("force-traversable") && this.servletContext != null && !(source instanceof TraversableSource)) { final Set children = this.servletContext.getResourcePaths(path + '/'); if (children != null) { source = new TraversableContextSource(source, children, this, path, scheme); } } return source; } final String message = location + " could not be found. (possible context problem)"; getLogger().info(message); throw new MalformedURLException(message); } catch (ServiceException se) { throw new SourceException("Unable to lookup source resolver.", se); } finally { this.manager.release(resolver); } } /** * @see org.apache.excalibur.source.SourceFactory#release(org.apache.excalibur.source.Source) */ public void release(Source source) { // In fact, this method should never be called as this factory // returns a source object from a different factory. So that // factory should release the source if (source != null) { if (getLogger().isDebugEnabled()) { getLogger().debug("Releasing source " + source.getURI()); } SourceResolver resolver = null; try { resolver = (SourceResolver) this.manager.lookup(SourceResolver.ROLE); if (source instanceof TraversableContextSource) { resolver.release(((TraversableContextSource) source).wrappedSource); } else { resolver.release(source); } } catch (ServiceException ingore) { // we ignore this } finally { this.manager.release(resolver); } } } /** * @see org.apache.excalibur.source.URIAbsolutizer#absolutize(java.lang.String, java.lang.String) */ public String absolutize(String baseURI, String location) { return SourceUtil.absolutize(baseURI, location, true); } }