processaction.java

jakarta-struts-1.2.4-src

            ActionForm form,
            HttpServletRequest request,
            HttpServletResponse response) {

            // Did someone leave us a forward?
        ActionForward forward = (ActionForward)
            request.getAttribute(Tokens.FAILURE);

        if (null==forward) {
                // No override, use default
            forward = super.findFailure(mapping,form,request,response);
        }
        else {
                // Clear advice from the request
            request.setAttribute(Tokens.FAILURE,null);
        }

        return forward;

    } // end findFailure


   /**
     * Optional extension point for pre-processing.
     * Default method does nothing.
     * To branch to another URI, return an non-null ActionForward.
     * If errors are logged (getErrors() et al),
     * default behaviour will branch to findFailure().
     *
     * @param mapping The ActionMapping used to select this instance
     * @param form The optional ActionForm bean for this request
     * @param request The HTTP request we are processing
     * @param response The resonse we are creating
     */
    protected void preProcess(
            ActionMapping mapping,
            ActionForm form,
            HttpServletRequest request,
            HttpServletResponse response) {

            // Check for cancelled
        ActionForward forward = mapping.findForward(Tokens.CANCEL);
        if ((null!=forward) && (isCancelled(request))) {
            // Our findFailure looks for this
            request.setAttribute(Tokens.FAILURE,forward);
           // Post cancel error message
           ActionErrors errors = getErrors(request,true);
           errors.add(ActionErrors.GLOBAL_ERROR,
                new ActionError(Tokens.ERROR_CANCEL));
            return;
         }

            // Check for missing token
        forward = mapping.findForward(Tokens.GET_TOKEN);
        if ((null!=forward) && (!isTokenValid(request))) {
            // Our findFailure looks for this
            request.setAttribute(Tokens.FAILURE,forward);
           // Post token error message
           ActionErrors errors = getErrors(request,true);
           errors.add(ActionErrors.GLOBAL_ERROR,
                new ActionError(Tokens.ERROR_TOKEN));
            return;
        }
        if (null!=forward) {
            // reset to guard against duplicate request
            resetToken(request);
        }

          // Check for save token directive (do this last)
        forward = mapping.findForward(Tokens.SET_TOKEN);
        if (null!=forward) saveToken(request);


     } // end preProcess


    /**
     * Check outcome, if any; recurse if container for other outcomes.
     *
     * @param mapping The ActionMapping used to select this instance
     * @param request The HTTP request we are processing
     * @param result The ProcessResult we are handling
     */
    protected void checkOutcome(
            ActionMapping mapping,
            HttpServletRequest request,
            HttpServletResponse response,
            ProcessResult result) throws Exception {

        if (result!=null) {

            servlet.log(Log.HELPER_OUTCOME,Log.DEBUG);

            if (result.isAggregate()) {
                    // recurse for each ProcessResult in collection
                Collection collection = (Collection)
                    result.getData();
                Iterator iterator = collection.iterator();
                while (iterator.hasNext()) {
                    ProcessResult nextResult =
                        (ProcessResult) iterator.next();
                    checkOutcome(mapping,request,response,nextResult);
                }
            }

            else {
                    // call extension points for whatever is returned
                if (result.isData())
                    checkData(mapping,request,response,result);

                if (result.isMessages())
                    checkMessages(mapping,request,response,result);

                if (result.isDispatch())
                    checkDispatch(mapping,request,response,result);
            }
        }

        else {
            throw new Exception(Log.PROCESS_RESULT_NULL);
        }

    } // end checkOutcome


    /**
     * Return the appropriate ActionForward for the nominal,
     * non-error state.
     * First checks for a SUCCESS ActionForward stored in the request.
     * If an override is not found, returns the result of the
     * superclass method.
     *
     * @param mapping The ActionMapping used to select this instance
     * @param form The optional ActionForm bean for this request (if any)
     * @param request The HTTP request we are processing
     * @param response The response we are creating
     * @return The ActionForward representing SUCCESS
     * or null if a SUCCESS forward has not been specified.
     */
    protected ActionForward findSuccess(
            ActionMapping mapping,
            ActionForm form,
            HttpServletRequest request,
            HttpServletResponse response) {

            // Did someone leave us a forward?
        ActionForward forward = (ActionForward)
            request.getAttribute(Tokens.SUCCESS);

        if (null==forward) {
                // No override, use default
            forward = super.findSuccess(mapping,form,request,response);
        }
        else {
                // Clear advice from the request
            request.setAttribute(Tokens.SUCCESS,null);
        }

        return forward;

    } // end findSuccess


    /**
     * Retrieve from session under known key
     * (<code>ProcessBean.USER_PROFILE_KEY</code>).
     * Override this approach to implement another method (e.g cookies).
     * Also revise UpdateProfile action-mapping to store changes.
     *
     * @param mapping The ActionMapping used to select this instance
     * @param form The ActionForm
     * @param request The HTTP request we are processing
     * @param response The HTTP response we are creating
     */
    protected BaseForm getUserProfile(
            ActionMapping mapping,
            ActionForm form,
            HttpServletRequest request,
            HttpServletResponse response) {

        return(BaseForm)
            request.getSession().getAttribute(ProcessBean.USER_PROFILE_KEY);

    } // end getUserProfile


    /**
     * Assume that helpers are ProcessBeans, execute each, and
     * process outcome.
     *
     * @param mapping The ActionMapping used to select this instance
     * @param form The ActionForm
     * @param request The HTTP request we are processing
     * @param response The HTTP response we are creating
     * @param helpers The object instantiated from type given as parameter.
     * @exception IOException if an input/output error occurs
     * @exception ServletException if a servlet exception occurs
     */
    protected void executeLogic(
            ActionMapping mapping,
            ActionForm form,
            HttpServletRequest request,
            HttpServletResponse response,
            Object[] helpers) throws Exception {

            // Retrieve user profile, if any
        BaseForm userBean =
            getUserProfile(mapping,form,request,response);

        servlet.log(Log.HELPER_PROCESSING,Log.DEBUG);
        Map properties = null;
        for (int i = 0; i < helpers.length; i++) {

                // Get helper instantiated by ancestor
            ProcessBean dataBean = (ProcessBean) helpers[i];

            properties = null;
            if (null!=form) {
                if (form instanceof BaseForm) {

                    BaseForm formBean = (BaseForm) form;

                        // Merge user profile (if found)
                        // and our form into a single map
                    servlet.log(Log.HELPER_POPULATE,Log.DEBUG);
                    properties = formBean.merge(userBean);

                        // Pass up the Locale, RemoteNode, and RemoteServer (if any)
                    dataBean.setLocale(formBean.getSessionLocale());
                    dataBean.setRemoteNode(getRemoteNode(request));
                    dataBean.setRemoteServer(getRemoteServer());
                }
                else {
                    properties = PropertyUtils.describe(form);
                }
            } // end null form
            else if (null!=userBean) {
                    // if no form, but is profile, still use profile
                properties = PropertyUtils.describe(userBean);
            }

                // Execute business logic, using values from  map
            servlet.log(Log.HELPER_EXECUTING,Log.DEBUG);
            ProcessResult result = (ProcessResult)
                dataBean.execute(properties);

                // Analyze result of business logic
            checkOutcome(mapping,request,response,result);

        } // end for

    } // end executeLogic

} // end ProcessAction