husted 01/10/03 19:12:02 Added: contrib/workflow RegistryServlet.java ActivityAction.java Log: Working drafts of an ActivityAction and RegistryServlet to integrate Struts with the new workflow proposal. These are early-release alpha files, but I thought I woudl get them up where others could see them. To see these in context, download struts-simple from ( husted.com/about/struts ). The Struts support is rudimentary. Beans and tags are being used but not ActionForwards. Revision Changes Path 1.1 jakarta-struts/contrib/workflow/RegistryServlet.java Index: RegistryServlet.java =================================================================== /* * $Header: /home/cvs/jakarta-struts/contrib/workflow/RegistryServlet.java,v 1.1 2001/10/04 02:12:02 husted Exp $ * $Revision: 1.1 $ * $Date: 2001/10/04 02:12:02 $ * * ==================================================================== * * The Apache Software License, Version 1.1 * * Copyright (c) 1999-2001 The Apache Software Foundation. All rights * reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * 3. The end-user documentation included with the redistribution, if * any, must include the following acknowlegement: * "This product includes software developed by the * Apache Software Foundation (http://www.apache.org/)." * Alternately, this acknowlegement may appear in the software itself, * if and wherever such third-party acknowlegements normally appear. * * 4. The names "The Jakarta Project", "Commons", and "Apache Software * Foundation" must not be used to endorse or promote products derived * from this software without prior written permission. For written * permission, please contact [EMAIL PROTECTED] * * 5. Products derived from this software may not be called "Apache" * nor may "Apache" appear in their names without prior written * permission of the Apache Group. * * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * ==================================================================== * * This software consists of voluntary contributions made by many * individuals on behalf of the Apache Software Foundation. For more * information on the Apache Software Foundation, please see * <http://www.apache.org/>. * */ package org.apache.struts.action; import java.io.InputStream; import java.io.IOException; import javax.servlet.ServletException; import javax.servlet.UnavailableException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession; import org.apache.commons.digester.Digester; import org.apache.commons.workflow.Activity; import org.apache.commons.workflow.Context; import org.apache.commons.workflow.ContextEvent; import org.apache.commons.workflow.ContextListener; import org.apache.commons.workflow.Step; import org.apache.commons.workflow.StepException; import org.apache.commons.workflow.base.BaseRuleSet; import org.apache.commons.workflow.core.CoreRuleSet; import org.apache.commons.workflow.io.IoRuleSet; import org.apache.commons.workflow.web.WebContext; import org.apache.commons.workflow.web.WebRuleSet; import simple.workflow.Registry; import simple.workflow.base.BaseRegistry; /** * <p>Demonstration servlet that illustrates one way that workflow support can * be integrated into Struts. This servlet is used to instantiate the Registry * of Activities and expose them to the application. Processing of the Activities * is expected to take place in an <code>Activity</code> Action.</p> * * <p>Note: The functionality of this Servlet could be replaced by the new * ServiceManager.</p> * * <p>Initialization parameters (defaults in square brackets):</p> * <ul> * <li><strong>registry</strong> - Context-relative resource path to the * definition file for the Activities to be initialized by this servlet.</li> * <li><strong>registry-key</strong> - Name of the session attribute under * which the <code>Registry</code> implementation is stored. * [org.apache.commons.workflow.REGISTRY]</li> * <li><strong>context-key</strong> - Name of the session attribute under * which our current <code>Context</code> implementation is stored. * [org.apache.commons.workflow.web.CONTEXT]</li> * <li><strong>debug</strong> - The debugging detail level for this * servlet, which controls how much information is logged. [0]</li> * <li><strong>detail</strong> - The debugging detail level for the Digester * we utilize in <code>initMapping()</code>, which logs to System.out * instead of the servlet log. [0]</li> * </ul> * * @author Craig R. McClanahan * @author Ted Husted * @version $Revision: 1.1 $ $Date: 2001/10/04 02:12:02 $ */ public class RegistryServlet extends HttpServlet { // ----------------------------------------------------- Instance Variables /** * The Activity for this servlet * //:TODO: TEMPORARY */ protected Activity activity = null; /** * Default Name of the session attribute under which * the current <code>Activity</code> is stored. */ public static String ACTIVITY = "org.apache.commons.workflow.ACTIVITY"; /** * Name of the session attribute under * which the <code>Activity</code> is stored. */ protected String activityKey = ACTIVITY; /** * Default Name of the session attribute under which * a current <code>Context</code> is stored. */ public static String CONTEXT = "org.apache.commons.workflow.CONTEXT"; /** * Name of the session attribute under * which a current <code>Context</code> is stored. */ protected String contextKey = CONTEXT; /** * The Registry for this servlet */ protected Registry registry = null; /** * Default Name of the application attribute under which * the <code>Registry</code> is stored. */ public static String REGISTRY = "org.apache.commons.workflow.REGISTRY"; /** * Name of the session attribute under * which the <code>Registry</code> is stored. */ protected String registryKey = REGISTRY; /** * Default name for Registry XML document */ protected String registryPath = "WEB-INF/workflow.xml"; /** * The debugging detail level for this servlet. */ private int debug = 0; /** * The debugging detail level for our Digester. */ private int detail = 0; // --------------------------------------------------------- Public Properties /** * Set the <code>Activity</code> associated with this instance. * * @param activity The new associated Activity */ public void setActivity(Activity activity) { this.activity = activity; getServletContext().setAttribute(ACTIVITY,this.activity); } /** * Return the name of the session attribute under which a current * <code>Context</code> is stored. */ public String getContextKey() { return contextKey; } /** * Set the name of the session attribute under which a current * <code>Context</code> is stored. */ protected void setContextKey(String contextKey) { this.contextKey = contextKey; } /** * Return Name of the application attribute under which this * servlet is exposed. */ public String getRegistryKey() { return registryKey; } /** * Set the name of the session attribute under which a current * <code>Registry</code> is stored. */ protected void setRegistryKey(String registryKey) { this.registryKey = registryKey; } /** * Return the Registry for this servlet */ protected Registry getRegistry() { return (this.registry); } /** * Set the <code>Registry</code> associated with this instance. * Called by Digester via parse. * * @param regisry The new associated Registry */ public void setRegistry(Registry registry) { this.registry = registry; initRegistry(); getServletContext().setAttribute( getRegistryKey(),getRegistry()); } // --------------------------------------------------------- Public Methods /** * Perform any optimizations or related tasks on Registry once it is * populated. */ protected void initRegistry() { synchronized (this.registry) { registry.initActivities(); } } /** * Gracefully shut down any activity instances we have created. */ protected void destroyRegistry() { synchronized (this.registry) { registry.clearActivities(); } } /** * Perform a graceful shutdown of this servlet instance. */ public void destroy() { destroyRegistry(); } /** * Perform a graceful startup of this servlet instance. * * @exception ServletException if we cannot process the activity * definition file for this activity */ public void init() throws ServletException { // Record the debugging detail level settings String debug = getServletConfig().getInitParameter("debug"); if (debug != null) { try { this.debug = Integer.parseInt(debug); } catch (NumberFormatException e) { throw new UnavailableException ("Debug initialization parameter must be an integer"); } } String detail = getServletConfig().getInitParameter("detail"); if (detail != null) { try { this.detail = Integer.parseInt(detail); } catch (NumberFormatException e) { throw new UnavailableException ("Detail initialization parameter must be an integer"); } } // Record the attribute name for our current Context String contextKey = getServletConfig().getInitParameter("context-key"); if (contextKey != null) setContextKey(contextKey); // Record the attribute name for our current Context String registryKey = getServletConfig().getInitParameter("registry-key"); if (registryKey != null) setRegistryKey(registryKey); // Parse the activity definition file for our Activity String registryPath = getServletConfig().getInitParameter("registry"); if (registryPath != null) this.registryPath = registryPath; parse(this.registryPath); // Check result of parse if (activity == null) throw new UnavailableException("No registry defined in resource " + registryPath); } // -------------------------------------------------------- Private Methods /** * Parse the specified activity definition file for this instance. * * @param path Context-relative resource path of the activity * definition file * * @exception ServletException on any processing error in parsing */ private void parse(String path) throws ServletException { // Get an input source for the specified path InputStream is = getServletContext().getResourceAsStream(path); if (is == null) throw new UnavailableException("Cannot access resource " + path); // Configure a Digester instance to parse our definition file Digester digester = new Digester(); digester.setDebug(detail); digester.setNamespaceAware(true); digester.setValidating(false); digester.push(this); // Add rules to recognize the built-in steps that we know about BaseRuleSet brs = new BaseRuleSet(); digester.addRuleSet(brs); digester.addRuleSet(new CoreRuleSet()); digester.addRuleSet(new IoRuleSet()); digester.addRuleSet(new WebRuleSet()); // Add a rule to register the Activity being created digester.setRuleNamespaceURI(brs.getNamespaceURI()); digester.addSetNext("activity", "setActivity", "org.apache.commons.workflow.Activity"); // Parse the activity definition file try { digester.parse(is); } catch (Throwable t) { log("Cannot parse resource " + path, t); throw new UnavailableException("Cannot parse resource " + path); } finally { try { is.close(); } catch (Throwable u) { ; } } } } 1.1 jakarta-struts/contrib/workflow/ActivityAction.java Index: ActivityAction.java =================================================================== /* * $Header: /home/cvs/jakarta-struts/contrib/workflow/ActivityAction.java,v 1.1 2001/10/04 02:12:02 husted Exp $ * $Revision: 1.1 $ * $Date: 2001/10/04 02:12:02 $ * * ==================================================================== * * The Apache Software License, Version 1.1 * * Copyright (c) 2001 The Apache Software Foundation. All rights * reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * 3. The end-user documentation included with the redistribution, if * any, must include the following acknowlegement: * "This product includes software developed by the * Apache Software Foundation (http://www.apache.org/)." * Alternately, this acknowlegement may appear in the software itself, * if and wherever such third-party acknowlegements normally appear. * * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software * Foundation" must not be used to endorse or promote products derived * from this software without prior written permission. For written * permission, please contact [EMAIL PROTECTED] * * 5. Products derived from this software may not be called "Apache" * nor may "Apache" appear in their names without prior written * permission of the Apache Group. * * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * ==================================================================== * * This software consists of voluntary contributions made by many * individuals on behalf of the Apache Software Foundation. For more * information on the Apache Software Foundation, please see * <http://www.apache.org/>. * */ package org.apache.struts.action; import java.io.IOException; import javax.servlet.RequestDispatcher; import javax.servlet.ServletException; import javax.servlet.ServletContext; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpSession; import javax.servlet.http.HttpServletResponse; import org.apache.struts.action.Action; import org.apache.struts.action.ActionError; import org.apache.struts.action.ActionErrors; import org.apache.struts.action.ActionForm; import org.apache.struts.action.ActionForward; import org.apache.struts.action.ActionMapping; import org.apache.struts.action.ActionServlet; import org.apache.commons.workflow.Activity; import org.apache.commons.workflow.Step; import org.apache.commons.workflow.StepException; import org.apache.commons.workflow.Context; import org.apache.commons.workflow.ContextEvent; import org.apache.commons.workflow.ContextListener; import org.apache.commons.workflow.Registry; import org.apache.commons.workflow.web.WebContext; /** * @author Craig McClanahan * @author Ted Husted * @version $Revision: 1.1 $ $Date: 2001/10/04 02:12:02 $ */ public class ActivityAction extends Action implements ContextListener { // --------------------------------------------------------- Instance Variables // ** FOR THREAD-SAFETY THESE MUST BE GLOBAL TO APPLICATION // ** AND NOT SPECIFIC TO A GIVEN REQUEST protected Registry registry = null; protected Activity activity = null; // --------------------------------------------------------- Protected Methods /** * Whether the debug level is set to verbose logging. */ protected boolean doDebugLog() { return ((servlet.getDebug() > 1)); } /** * Whether the debug level is set to listening. */ protected boolean doDebugListener() { return ((servlet.getDebug() > 2)); } /** * Return Activity by ID */ protected Activity getActivity(String id) { // return (registry.getActivity(id)); return this.activity; } /** * Return Activity by looking up ID in mapping. */ protected Activity getActivity(ActionMapping mapping) { return (getActivity(mapping.getParameter())); } /** * Return context, instantiating it if necessary. */ protected WebContext getContext(ActionMapping mapping, HttpServletRequest request, HttpServletResponse response) { String contextId = mapping.getParameter(); HttpSession session = request.getSession(); WebContext context = (WebContext) session.getAttribute(contextId); if (context == null) { if (doDebugLog()) servlet.log("{" + session.getId() + "} Creating new Context"); context = new WebContext(); // context.setActivity(getActivity(contextId)); context.setActivity(activity); context.setHttpSession(session); context.setServletContext(servlet.getServletContext()); if (doDebugListener()) context.addContextListener(this); session.setAttribute(contextId, context); context.call(context.getActivity()); } return context; } /** * Validate context, returning errors if found. */ protected void validateInit(ActionErrors errors, Context context, Activity activity) { if ((context==null) || (context.getActivity()==null)) { errors.add(ActionErrors.GLOBAL_ERROR, new ActionError("action.missing.parameter")); } } /** * Execute the next stage of the current Activity */ protected void executeContext(WebContext context, Activity activity, ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response) throws ServletException { synchronized (context) { // If we are not already executing our associated Activity, call it if (!activity.equals(context.getActivity())) { if (doDebugLog()) servlet.log("{" + request.getSession().getId() + "} calling Activity " + activity.getId()); context.call(activity); } // Associate our context with the current request and response context.setServletRequest(request); context.setServletResponse(response); // Execute our activity until suspended or ended try { if (doDebugLog()) servlet.log("{" + context.getHttpSession().getId() + "} executing Activity " + context.getActivity().getId()); context.execute(); } catch (StepException e) { if (e.getCause() == null) throw new ServletException(e.getMessage(), e); else throw new ServletException(e.getMessage(), e.getCause()); } } } /** * Analyze initialization properties, * and report any errors. */ protected void validateContext(ActionErrors errors, Context context) { } /** * Analyze result, and determine next forward. * <p> * If no errors, forward for id of next step is returned. * <p> * If there are errors, save errors to request, and * forward to input. If there is not input property, * then forward to local or global "errors" forwarding. */ protected ActionForward nextForward(ActionMapping mapping, ActionErrors errors, HttpServletRequest request, WebContext context) { if (!errors.empty()) { // Save for display saveErrors(request,errors); // Return to input page, if there is one if (mapping.getInput()!=null) return (new ActionForward(mapping.getInput())); // If no input page, use error forwarding return (mapping.findForward("error")); } // If no errors, goto forwarding for next step return (mapping.findForward( context.getNextStep().getId())); } // --------------------------------------------------------- Public Properties /** * Set the Registry for this Action (or application) */ public void setRegistry(Registry registry) { this.registry = registry; } // --------------------------------------------------------- Public Methods /** * Set the controller servlet instance to which we are attached * (if servlet is non-null), or release any allocated resources * (if servlet is null). * Call setRegistry to obtain registry from servlet context. */ public void setServlet(ActionServlet servlet) { super.setServlet(servlet); if (servlet==null) { setRegistry(null); this.activity = null; } else { setRegistry((Registry) servlet.getServletContext().getAttribute( RegistryServlet.REGISTRY)); this.activity = (Activity) servlet.getServletContext().getAttribute( RegistryServlet.ACTIVITY); } } /** * Retrieve or initialize context from session, using ActionMapping * parameter as key. Returns action.missing.parameters if parameter * missing or not found. Executes the next step of the actitivity. * * @param mapping The ActionMapping used to select this instance * @param actionForm The optional ActionForm bean for this request (if any) * @param request The HTTP request we are processing * @param response The HTTP response we are creating * * @exception IOException if an input/output error occurs * @exception ServletException if a servlet exception occurs */ public ActionForward perform(ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException { ActionErrors errors = new ActionErrors(); WebContext context = getContext(mapping,request, response); Activity activity = getActivity(mapping); validateInit(errors,context,activity); if (errors.empty()) { executeContext(context,activity, mapping,form,request,response); } validateContext(errors,context); // return (nextForward(mapping,errors,request,context)); return null; } // end ActionForward // ------------------------------------------------ ContextListener Methods /** * Invoked immediately after execution of the related Activity has * been completed normally, been suspended, or been aborted by * the throwing of a StepException. The Step included in this event * will be the last one to be executed. * * @param event The <code>ContextEvent</code> that has occurred */ public void afterActivity(ContextEvent event) { WebContext context = (WebContext) event.getContext(); HttpSession session = context.getHttpSession(); StringBuffer sb = new StringBuffer("{"); sb.append(session.getId()); sb.append("} afterActivity"); servlet.log(sb.toString()); } /** * Invoked immediately after the specified Step was executed. * * @param event The <code>ContextEvent</code> that has occurred */ public void afterStep(ContextEvent event) { WebContext context = (WebContext) event.getContext(); HttpSession session = context.getHttpSession(); StringBuffer sb = new StringBuffer("{"); sb.append(session.getId()); sb.append("} afterStep "); sb.append(event.getStep()); if (context.getSuspend()) sb.append(" (Suspended)"); if (context.getNextStep() == null) sb.append(" (Finished)"); servlet.log(sb.toString()); if (event.getException() != null) servlet.log("-->Step threw exception", event.getException()); } /** * Invoked immediately before execution of the related Activity has * started. The Step included in this event will be the first one * to be executed. * * @param event The <code>ContextEvent</code> that has occurred */ public void beforeActivity(ContextEvent event) { WebContext context = (WebContext) event.getContext(); HttpSession session = context.getHttpSession(); StringBuffer sb = new StringBuffer("{"); sb.append(session.getId()); sb.append("} beforeActivity"); servlet.log(sb.toString()); } /** * Invoked immediately before the specified Step is executed. * * @param event The <code>ContextEvent</code> that has occurred */ public void beforeStep(ContextEvent event) { WebContext context = (WebContext) event.getContext(); HttpSession session = context.getHttpSession(); StringBuffer sb = new StringBuffer("{"); sb.append(session.getId()); sb.append("} beforeStep "); sb.append(event.getStep()); servlet.log(sb.toString()); } } // end Activity
