| /* |
| * Copyright 1999-2004 The Apache Software Foundation. |
| * |
| * Licensed 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.flow; |
| |
| import java.io.OutputStream; |
| import java.util.ArrayList; |
| import java.util.Map; |
| |
| import org.apache.avalon.framework.activity.Disposable; |
| import org.apache.avalon.framework.configuration.Configurable; |
| import org.apache.avalon.framework.configuration.Configuration; |
| import org.apache.avalon.framework.configuration.ConfigurationException; |
| import org.apache.avalon.framework.context.ContextException; |
| import org.apache.avalon.framework.context.Contextualizable; |
| import org.apache.avalon.framework.logger.AbstractLogEnabled; |
| 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.SingleThreaded; |
| import org.apache.cocoon.Constants; |
| import org.apache.cocoon.components.ContextHelper; |
| import org.apache.cocoon.components.flow.util.PipelineUtil; |
| import org.apache.cocoon.core.Core; |
| import org.apache.cocoon.core.Settings; |
| import org.apache.cocoon.environment.Context; |
| import org.apache.cocoon.environment.Redirector; |
| import org.apache.excalibur.source.SourceUtil; |
| |
| /** |
| * Abstract superclass for various scripting languages used by Cocoon |
| * for flow control. Defines some useful behavior like the ability to |
| * reload script files if they get modified (useful when doing |
| * development), and passing the control to Cocoon's sitemap for |
| * result page generation. |
| * <p> |
| * Flow intrepreters belonging to different sitemaps should be isolated. To achieve this, |
| * class implements the {@link org.apache.avalon.framework.thread.SingleThreaded}. Since |
| * the sitemap engine looks up the flow intepreter once at sitemap build time, this ensures |
| * that each sitemap will use a different instance of this class. But that instance will |
| * handle all flow calls for a given sitemap, and must therefore be thread safe. |
| * |
| * @since March 15, 2002 |
| * @version $Id$ |
| */ |
| public abstract class AbstractInterpreter |
| extends AbstractLogEnabled |
| implements Serviceable, Contextualizable, Interpreter, |
| SingleThreaded, Configurable, Disposable { |
| |
| // The instance ID of this interpreter, used to identify user scopes |
| private String instanceID; |
| |
| protected org.apache.avalon.framework.context.Context avalonContext; |
| |
| /** |
| * List of source locations that need to be resolved. |
| */ |
| protected ArrayList needResolve = new ArrayList(); |
| |
| protected org.apache.cocoon.environment.Context context; |
| protected ServiceManager manager; |
| protected ContinuationsManager continuationsMgr; |
| |
| /** The settings of Cocoon. */ |
| protected Settings settings; |
| |
| /** |
| * Whether reloading of scripts should be done. Specified through |
| * the "reload-scripts" attribute in <code>flow.xmap</code>. |
| */ |
| protected boolean reloadScripts; |
| |
| /** |
| * Interval between two checks for modified script files. Specified |
| * through the "check-time" XML attribute in <code>flow.xmap</code>. |
| */ |
| protected long checkTime; |
| |
| /** |
| * Set the unique ID for this interpreter, which can be used to distinguish user value scopes |
| * attached to the session. |
| */ |
| public void setInterpreterID(String interpreterID) { |
| this.instanceID = interpreterID; |
| } |
| |
| /** |
| * Get the unique ID for this interpreter, which can be used to distinguish user value scopes |
| * attached to the session. |
| * |
| * @return a unique ID for this interpreter |
| */ |
| public String getInterpreterID() { |
| return this.instanceID; |
| } |
| |
| /** |
| * @see org.apache.avalon.framework.configuration.Configurable#configure(org.apache.avalon.framework.configuration.Configuration) |
| */ |
| public void configure(Configuration config) throws ConfigurationException { |
| this.reloadScripts = config.getChild("reload-scripts").getValueAsBoolean(this.settings.isReloadingEnabled("flow")); |
| this.checkTime = config.getChild("check-time").getValueAsLong(this.settings.getReloadDelay("flow")); |
| } |
| |
| /** |
| * @see org.apache.avalon.framework.service.Serviceable#service(org.apache.avalon.framework.service.ServiceManager) |
| */ |
| public void service(ServiceManager sm) throws ServiceException { |
| this.manager = sm; |
| this.continuationsMgr = (ContinuationsManager)sm.lookup(ContinuationsManager.ROLE); |
| final Core core = (Core)this.manager.lookup(Core.ROLE); |
| this.settings = core.getSettings(); |
| this.manager.release(core); |
| } |
| |
| /** |
| * @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.avalonContext = context; |
| this.context = (Context)context.get(Constants.CONTEXT_ENVIRONMENT_CONTEXT); |
| } |
| |
| /** |
| * @see org.apache.avalon.framework.activity.Disposable#dispose() |
| */ |
| public void dispose() { |
| if ( this.manager != null ) { |
| this.manager.release( this.continuationsMgr ); |
| this.continuationsMgr = null; |
| this.manager = null; |
| this.settings = null; |
| } |
| } |
| |
| /** |
| * Registers a source file with the interpreter. Using this method |
| * an implementation keeps track of all the script files which are |
| * compiled. This allows them to reload the script files which get |
| * modified on the file system. |
| * |
| * <p>The parsing/compilation of a script file by an interpreter |
| * happens in two phases. In the first phase the file's location is |
| * registered in the <code>needResolve</code> array. |
| * |
| * <p>The second is possible only when a Cocoon |
| * <code>Environment</code> is passed to the Interpreter. This |
| * allows the file location to be resolved using Cocoon's |
| * <code>SourceFactory</code> class. |
| * |
| * <p>Once a file's location can be resolved, it is removed from the |
| * <code>needResolve</code> array and placed in the |
| * <code>scripts</code> hash table. The key in this hash table is |
| * the file location string, and the value is a |
| * DelayedRefreshSourceWrapper instance which keeps track of when |
| * the file needs to re-read. |
| * |
| * @param source the location of the script |
| * |
| * @see org.apache.cocoon.environment.Environment |
| * @see org.apache.cocoon.components.source.impl.DelayedRefreshSourceWrapper |
| */ |
| public void register(String source) { |
| synchronized (this) { |
| needResolve.add(source); |
| } |
| } |
| |
| /** |
| * Call the Cocoon sitemap for the given URI, sending the output of the |
| * eventually matched pipeline to the specified outputstream. |
| * |
| * @param uri The URI for which the request should be generated. |
| * @param biz Extra data associated with the subrequest. |
| * @param out An OutputStream where the output should be written to. |
| * @exception Exception If an error occurs. |
| */ |
| protected void process(String uri, Object biz, OutputStream out) |
| throws Exception { |
| // FIXME (SW): should we deprecate this method in favor of PipelineUtil? |
| PipelineUtil pipeUtil = new PipelineUtil(); |
| try { |
| pipeUtil.contextualize(this.avalonContext); |
| pipeUtil.service(this.manager); |
| pipeUtil.processToStream(uri, biz, out); |
| } finally { |
| pipeUtil.dispose(); |
| } |
| } |
| |
| /** |
| * @see org.apache.cocoon.components.flow.Interpreter#forwardTo(java.lang.String, java.lang.Object, org.apache.cocoon.components.flow.WebContinuation, org.apache.cocoon.environment.Redirector) |
| */ |
| public void forwardTo(String uri, Object bizData, |
| WebContinuation continuation, |
| Redirector redirector) |
| throws Exception { |
| if (SourceUtil.indexOfSchemeColon(uri) == -1) { |
| uri = "cocoon:/" + uri; |
| Map objectModel = ContextHelper.getObjectModel(this.avalonContext); |
| FlowHelper.setWebContinuation(objectModel, continuation); |
| FlowHelper.setContextObject(objectModel, bizData); |
| if (redirector.hasRedirected()) { |
| throw new IllegalStateException("Pipeline has already been processed for this request"); |
| } |
| // this is a hint for the redirector |
| objectModel.put("cocoon:forward", "true"); |
| redirector.redirect(false, uri); |
| } else { |
| throw new Exception("uri is not allowed to contain a scheme (cocoon:/ is always automatically used)"); |
| } |
| } |
| } |
