requestprocessor.java.svn-base

MVC开源框架

        // For extension matching, strip the module prefix and extension
        path = (String) request.getAttribute(INCLUDE_SERVLET_PATH);

        if (path == null) {
            path = request.getServletPath();
        }

        String prefix = moduleConfig.getPrefix();

        if (!path.startsWith(prefix)) {
            String msg = getInternal().getMessage("processPath");

            log.error(msg + " " + request.getRequestURI());
            response.sendError(HttpServletResponse.SC_BAD_REQUEST, msg);

            return null;
        }

        path = path.substring(prefix.length());

        int slash = path.lastIndexOf("/");
        int period = path.lastIndexOf(".");

        if ((period >= 0) && (period > slash)) {
            path = path.substring(0, period);
        }

        return (path);
    }

    /**
     * <p>Populate the properties of the specified <code>ActionForm</code>
     * instance from the request parameters included with this request.  In
     * addition, request attribute <code>Globals.CANCEL_KEY</code> will be set
     * if the request was submitted with a button created by
     * <code>CancelTag</code>.</p>
     *
     * @param request  The servlet request we are processing
     * @param response The servlet response we are creating
     * @param form     The ActionForm instance we are populating
     * @param mapping  The ActionMapping we are using
     * @throws ServletException if thrown by RequestUtils.populate()
     */
    protected void processPopulate(HttpServletRequest request,
        HttpServletResponse response, ActionForm form, ActionMapping mapping)
        throws ServletException {
        if (form == null) {
            return;
        }

        // Populate the bean properties of this ActionForm instance
        if (log.isDebugEnabled()) {
            log.debug(" Populating bean properties from this request");
        }

        form.setServlet(this.servlet);
        form.reset(mapping, request);

        if (mapping.getMultipartClass() != null) {
            request.setAttribute(Globals.MULTIPART_KEY,
                mapping.getMultipartClass());
        }

        RequestUtils.populate(form, mapping.getPrefix(), mapping.getSuffix(),
            request);

        // Set the cancellation request attribute if appropriate
        if ((request.getParameter(Globals.CANCEL_PROPERTY) != null)
            || (request.getParameter(Globals.CANCEL_PROPERTY_X) != null)) {
            request.setAttribute(Globals.CANCEL_KEY, Boolean.TRUE);
        }
    }

    /**
     * <p>General-purpose preprocessing hook that can be overridden as
     * required by subclasses. Return <code>true</code> if you want standard
     * processing to continue, or <code>false</code> if the response has
     * already been completed. The default implementation does nothing.</p>
     *
     * @param request  The servlet request we are processing
     * @param response The servlet response we are creating
     * @return <code>true</code> to continue normal processing;
     *         <code>false</code> if a response has been created.
     */
    protected boolean processPreprocess(HttpServletRequest request,
        HttpServletResponse response) {
        return (true);
    }

    /**
     * <p>If this action is protected by security roles, make sure that the
     * current user possesses at least one of them.  Return <code>true</code>
     * to continue normal processing, or <code>false</code> if an appropriate
     * response has been created and processing should terminate.</p>
     *
     * @param request  The servlet request we are processing
     * @param response The servlet response we are creating
     * @param mapping  The mapping we are using
     * @return <code>true</code> to continue normal processing;
     *         <code>false</code> if a response has been created.
     * @throws IOException      if an input/output error occurs
     * @throws ServletException if a servlet exception occurs
     */
    protected boolean processRoles(HttpServletRequest request,
        HttpServletResponse response, ActionMapping mapping)
        throws IOException, ServletException {
        // Is this action protected by role requirements?
        String[] roles = mapping.getRoleNames();

        if ((roles == null) || (roles.length < 1)) {
            return (true);
        }

        // Check the current user against the list of required roles
        for (int i = 0; i < roles.length; i++) {
            if (request.isUserInRole(roles[i])) {
                if (log.isDebugEnabled()) {
                    log.debug(" User '" + request.getRemoteUser()
                        + "' has role '" + roles[i] + "', granting access");
                }

                return (true);
            }
        }

        // The current user is not authorized for this action
        if (log.isDebugEnabled()) {
            log.debug(" User '" + request.getRemoteUser()
                + "' does not have any required role, denying access");
        }

        response.sendError(HttpServletResponse.SC_FORBIDDEN,
            getInternal().getMessage("notAuthorized", mapping.getPath()));

        return (false);
    }

    /**
     * <p>If this request was not cancelled, and the request's {@link
     * ActionMapping} has not disabled validation, call the
     * <code>validate</code> method of the specified {@link ActionForm}, and
     * forward to the input path if there were any errors. Return
     * <code>true</code> if we should continue processing, or
     * <code>false</code> if we have already forwarded control back to the
     * input form.</p>
     *
     * @param request  The servlet request we are processing
     * @param response The servlet response we are creating
     * @param form     The ActionForm instance we are populating
     * @param mapping  The ActionMapping we are using
     * @return <code>true</code> to continue normal processing;
     *         <code>false</code> if a response has been created.
     * @throws IOException      if an input/output error occurs
     * @throws ServletException if a servlet exception occurs
     * @throws InvalidCancelException if a cancellation is attempted
     *         without the proper action configuration.
     */
    protected boolean processValidate(HttpServletRequest request,
        HttpServletResponse response, ActionForm form, ActionMapping mapping)
        throws IOException, ServletException, InvalidCancelException {
        if (form == null) {
            return (true);
        }

        // Has validation been turned off for this mapping?
        if (!mapping.getValidate()) {
            return (true);
        }

        // Was this request cancelled? If it has been, the mapping also
        // needs to state whether the cancellation is permissable; otherwise
        // the cancellation is considered to be a symptom of a programmer
        // error or a spoof.
        if (request.getAttribute(Globals.CANCEL_KEY) != null) {
            if (mapping.getCancellable()) {
                if (log.isDebugEnabled()) {
                    log.debug(" Cancelled transaction, skipping validation");
                }
                return (true);
            } else {
                request.removeAttribute(Globals.CANCEL_KEY);
                throw new InvalidCancelException();
            }
        }

        // Call the form bean's validation method
        if (log.isDebugEnabled()) {
            log.debug(" Validating input form properties");
        }

        ActionMessages errors = form.validate(mapping, request);

        if ((errors == null) || errors.isEmpty()) {
            if (log.isTraceEnabled()) {
                log.trace("  No errors detected, accepting input");
            }

            return (true);
        }

        // Special handling for multipart request
        if (form.getMultipartRequestHandler() != null) {
            if (log.isTraceEnabled()) {
                log.trace("  Rolling back multipart request");
            }

            form.getMultipartRequestHandler().rollback();
        }

        // Was an input path (or forward) specified for this mapping?
        String input = mapping.getInput();

        if (input == null) {
            if (log.isTraceEnabled()) {
                log.trace("  Validation failed but no input form available");
            }

            response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR,
                getInternal().getMessage("noInput", mapping.getPath()));

            return (false);
        }

        // Save our error messages and return to the input form if possible
        if (log.isDebugEnabled()) {
            log.debug(" Validation failed, returning to '" + input + "'");
        }

        request.setAttribute(Globals.ERROR_KEY, errors);

        if (moduleConfig.getControllerConfig().getInputForward()) {
            ForwardConfig forward = mapping.findForward(input);

            processForwardConfig(request, response, forward);
        } else {
            internalModuleRelativeForward(input, request, response);
        }

        return (false);
    }

    /**
     * <p>Do a module relative forward to specified URI using request
     * dispatcher. URI is relative to the current module. The real URI is
     * compute by prefixing the module name.</p> <p>This method is used
     * internally and is not part of the public API. It is advised to not use
     * it in subclasses. </p>
     *
     * @param uri      Module-relative URI to forward to
     * @param request  Current page request
     * @param response Current page response
     * @throws IOException      if an input/output error occurs
     * @throws ServletException if a servlet exception occurs
     * @since Struts 1.1
     */
    protected void internalModuleRelativeForward(String uri,
        HttpServletRequest request, HttpServletResponse response)
        throws IOException, ServletException {
        // Construct a request dispatcher for the specified path
        uri = moduleConfig.getPrefix() + uri;

        // Delegate the processing of this request
        // :FIXME: - exception handling?
        if (log.isDebugEnabled()) {
            log.debug(" Delegating via forward to '" + uri + "'");
        }

        doForward(uri, request, response);
    }

    /**
     * <p>Do a module relative include to specified URI using request
     * dispatcher. URI is relative to the current module. The real URI is
     * compute by prefixing the module name.</p> <p>This method is used
     * internally and is not part of the public API. It is advised to not use
     * it in subclasses.</p>
     *
     * @param uri      Module-relative URI to include
     * @param request  Current page request
     * @param response Current page response
     * @throws IOException      if an input/output error occurs
     * @throws ServletException if a servlet exception occurs
     * @since Struts 1.1
     */
    protected void internalModuleRelativeInclude(String uri,
        HttpServletRequest request, HttpServletResponse response)
        throws IOException, ServletException {
        // Construct a request dispatcher for the specified path
        uri = moduleConfig.getPrefix() + uri;

        // Delegate the processing of this request
        // FIXME - exception handling?
        if (log.isDebugEnabled()) {
            log.debug(" Delegating via include to '" + uri + "'");
        }

        doInclude(uri, request, response);
    }

    /**
     * <p>Do a forward to specified URI using a <code>RequestDispatcher</code>.
     * This method is used by all internal method needing to do a
     * forward.</p>
     *
     * @param uri      Context-relative URI to forward to
     * @param request  Current page request
     * @param response Current page response
     * @throws IOException      if an input/output error occurs
     * @throws ServletException if a servlet exception occurs
     * @since Struts 1.1
     */
    protected void doForward(String uri, HttpServletRequest request,
        HttpServletResponse response)
        throws IOException, ServletException {
        RequestDispatcher rd = getServletContext().getRequestDispatcher(uri);

        if (rd == null) {
            response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR,
                getInternal().getMessage("requestDispatcher", uri));

            return;
        }

        rd.forward(request, response);
    }

    /**
     * <p>Do an include of specified URI using a <code>RequestDispatcher</code>.
     * This method is used by all internal method needing to do an
     * include.</p>
     *
     * @param uri      Context-relative URI to include
     * @param request  Current page request
     * @param response Current page response
     * @throws IOException      if an input/output error occurs
     * @throws ServletException if a servlet exception occurs
     * @since Struts 1.1
     */
    protected void doInclude(String uri, HttpServletRequest request,
        HttpServletResponse response)
        throws IOException, ServletException {
        RequestDispatcher rd = getServletContext().getRequestDispatcher(uri);

        if (rd == null) {
            response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR,
                getInternal().getMessage("requestDispatcher", uri));

            return;
        }

        rd.include(request, response);
    }

    // -------------------------------------------------------- Support Methods

    /**
     * <p>Return the <code>MessageResources</code> instance containing our
     * internal message strings.</p>
     *
     * @return The <code>MessageResources</code> instance containing our
     *         internal message strings.
     */
    protected MessageResources getInternal() {
        return (servlet.getInternal());
    }

    /**
     * <p>Return the <code>ServletContext</code> for the web application in
     * which we are running.</p>
     *
     * @return The <code>ServletContext</code> for the web application.
     */
    protected ServletContext getServletContext() {
        return (servlet.getServletContext());
    }
}