requestutils.java.svn-base

MVC开源框架

     * reserved.)</li>
     *
     * </ul></li>
     *
     * </ul>
     *
     * @param request The servlet request we are processing
     * @param forward ForwardConfig to be evaluated
     * @return context-relative URL
     * @since Struts 1.1
     */
    public static String forwardURL(HttpServletRequest request,
        ForwardConfig forward) {
        return forwardURL(request, forward, null);
    }

    /**
     * <p>Return the context-relative URL that corresponds to the specified
     * <code>ForwardConfig</code>. The URL is calculated based on the
     * properties of the {@link ForwardConfig} instance as follows:</p>
     *
     * <ul>
     *
     * <li>If the <code>contextRelative</code> property is set, it is assumed
     * that the <code>path</code> property contains a path that is already
     * context-relative: <ul>
     *
     * <li>If the <code>path</code> property value starts with a slash, it is
     * returned unmodified.</li> <li>If the <code>path</code> property value
     * does not start with a slash, a slash is prepended.</li>
     *
     * </ul></li>
     *
     * <li>Acquire the <code>forwardPattern</code> property from the
     * <code>ControllerConfig</code> for the application module used to
     * process this request. If no pattern was configured, default to a
     * pattern of <code>$M$P</code>, which is compatible with the hard-coded
     * mapping behavior in Struts 1.0.</li>
     *
     * <li>Process the acquired <code>forwardPattern</code>, performing the
     * following substitutions: <ul> <li><strong>$M</strong> - Replaced by the
     * module prefix for the application module processing this request.</li>
     *
     * <li><strong>$P</strong> - Replaced by the <code>path</code> property of
     * the specified {@link ForwardConfig}, prepended with a slash if it does
     * not start with one.</li>
     *
     * <li><strong>$$</strong> - Replaced by a single dollar sign
     * character.</li>
     *
     * <li><strong>$x</strong> (where "x" is any charater not listed above) -
     * Silently omit these two characters from the result value.  (This has
     * the side effect of causing all other $+letter combinations to be
     * reserved.)</li>
     *
     * </ul></li></ul>
     *
     * @param request      The servlet request we are processing
     * @param forward      ForwardConfig to be evaluated
     * @param moduleConfig Base forward on this module config.
     * @return context-relative URL
     * @since Struts 1.2
     */
    public static String forwardURL(HttpServletRequest request,
        ForwardConfig forward, ModuleConfig moduleConfig) {
        //load the current moduleConfig, if null
        if (moduleConfig == null) {
            moduleConfig = ModuleUtils.getInstance().getModuleConfig(request);
        }

        String path = forward.getPath();

        //load default prefix
        String prefix = moduleConfig.getPrefix();

        //override prefix if supplied by forward
        if (forward.getModule() != null) {
            prefix = forward.getModule();

            if ("/".equals(prefix)) {
                prefix = "";
            }
        }

        StringBuffer sb = new StringBuffer();

        // Calculate a context relative path for this ForwardConfig
        String forwardPattern =
            moduleConfig.getControllerConfig().getForwardPattern();

        if (forwardPattern == null) {
            // Performance optimization for previous default behavior
            sb.append(prefix);

            // smoothly insert a '/' if needed
            if (!path.startsWith("/")) {
                sb.append("/");
            }

            sb.append(path);
        } else {
            boolean dollar = false;

            for (int i = 0; i < forwardPattern.length(); i++) {
                char ch = forwardPattern.charAt(i);

                if (dollar) {
                    switch (ch) {
                    case 'M':
                        sb.append(prefix);

                        break;

                    case 'P':

                        // add '/' if needed
                        if (!path.startsWith("/")) {
                            sb.append("/");
                        }

                        sb.append(path);

                        break;

                    case '$':
                        sb.append('$');

                        break;

                    default:
                        ; // Silently swallow
                    }

                    dollar = false;

                    continue;
                } else if (ch == '$') {
                    dollar = true;
                } else {
                    sb.append(ch);
                }
            }
        }

        return (sb.toString());
    }

    /**
     * <p>Return the URL representing the current request. This is equivalent
     * to <code>HttpServletRequest.getRequestURL</code> in Servlet 2.3.</p>
     *
     * @param request The servlet request we are processing
     * @return URL representing the current request
     * @throws MalformedURLException if a URL cannot be created
     */
    public static URL requestURL(HttpServletRequest request)
        throws MalformedURLException {
        StringBuffer url = requestToServerUriStringBuffer(request);

        return (new URL(url.toString()));
    }

    /**
     * <p>Return the URL representing the scheme, server, and port number of
     * the current request. Server-relative URLs can be created by simply
     * appending the server-relative path (starting with '/') to this.</p>
     *
     * @param request The servlet request we are processing
     * @return URL representing the scheme, server, and port number of the
     *         current request
     * @throws MalformedURLException if a URL cannot be created
     */
    public static URL serverURL(HttpServletRequest request)
        throws MalformedURLException {
        StringBuffer url = requestToServerStringBuffer(request);

        return (new URL(url.toString()));
    }

    /**
     * <p>Return the string representing the scheme, server, and port number
     * of the current request. Server-relative URLs can be created by simply
     * appending the server-relative path (starting with '/') to this.</p>
     *
     * @param request The servlet request we are processing
     * @return URL representing the scheme, server, and port number of the
     *         current request
     * @since Struts 1.2.0
     */
    public static StringBuffer requestToServerUriStringBuffer(
        HttpServletRequest request) {
        StringBuffer serverUri =
            createServerUriStringBuffer(request.getScheme(),
                request.getServerName(), request.getServerPort(),
                request.getRequestURI());

        return serverUri;
    }

    /**
     * <p>Return <code>StringBuffer</code> representing the scheme, server,
     * and port number of the current request. Server-relative URLs can be
     * created by simply appending the server-relative path (starting with
     * '/') to this.</p>
     *
     * @param request The servlet request we are processing
     * @return URL representing the scheme, server, and port number of the
     *         current request
     * @since Struts 1.2.0
     */
    public static StringBuffer requestToServerStringBuffer(
        HttpServletRequest request) {
        return createServerStringBuffer(request.getScheme(),
            request.getServerName(), request.getServerPort());
    }

    /**
     * <p>Return <code>StringBuffer</code> representing the scheme, server,
     * and port number of the current request.</p>
     *
     * @param scheme The scheme name to use
     * @param server The server name to use
     * @param port   The port value to use
     * @return StringBuffer in the form scheme: server: port
     * @since Struts 1.2.0
     */
    public static StringBuffer createServerStringBuffer(String scheme,
        String server, int port) {
        StringBuffer url = new StringBuffer();

        if (port < 0) {
            port = 80; // Work around java.net.URL bug
        }

        url.append(scheme);
        url.append("://");
        url.append(server);

        if ((scheme.equals("http") && (port != 80))
            || (scheme.equals("https") && (port != 443))) {
            url.append(':');
            url.append(port);
        }

        return url;
    }

    /**
     * <p>Return <code>StringBuffer</code> representing the scheme, server,
     * and port number of the current request.</p>
     *
     * @param scheme The scheme name to use
     * @param server The server name to use
     * @param port   The port value to use
     * @param uri    The uri value to use
     * @return StringBuffer in the form scheme: server: port
     * @since Struts 1.2.0
     */
    public static StringBuffer createServerUriStringBuffer(String scheme,
        String server, int port, String uri) {
        StringBuffer serverUri = createServerStringBuffer(scheme, server, port);

        serverUri.append(uri);

        return serverUri;
    }

    /**
     * <p>Returns the true path of the destination action if the specified forward
     * is an action-aliased URL. This method version forms the URL based on
     * the current request; selecting the current module if the forward does not
     * explicitly contain a module path.</p>
     *
     * @param forward the forward config
     * @param request the current request
     * @param servlet the servlet handling the current request
     * @return the context-relative URL of the action if the forward has an action identifier; otherwise <code>null</code>.
     * @since Struts 1.3.6
     */
    public static String actionIdURL(ForwardConfig forward, HttpServletRequest request, ActionServlet servlet) {
        ModuleConfig moduleConfig = null;
        if (forward.getModule() != null) {
            String prefix = forward.getModule();
            moduleConfig = ModuleUtils.getInstance().getModuleConfig(prefix, servlet.getServletContext());
        } else {
            moduleConfig = ModuleUtils.getInstance().getModuleConfig(request);
        }
        return actionIdURL(forward.getPath(), moduleConfig, servlet);
    }

    /**
     * <p>Returns the true path of the destination action if the specified forward
     * is an action-aliased URL. This method version forms the URL based on
     * the specified module.
     *
     * @param originalPath the action-aliased path
     * @param moduleConfig the module config for this request
     * @param servlet the servlet handling the current request
     * @return the context-relative URL of the action if the path has an action identifier; otherwise <code>null</code>.
     * @since Struts 1.3.6
     */
    public static String actionIdURL(String originalPath, ModuleConfig moduleConfig, ActionServlet servlet) {
        if (originalPath.startsWith("http") || originalPath.startsWith("/")) {
            return null;
        }

        // Split the forward path into the resource and query string;
        // it is possible a forward (or redirect) has added parameters.
        String actionId = null;
        String qs = null;
        int qpos = originalPath.indexOf("?");
        if (qpos == -1) {
            actionId = originalPath;
        } else {
            actionId = originalPath.substring(0, qpos);
            qs = originalPath.substring(qpos);
        }

        // Find the action of the given actionId
        ActionConfig actionConfig = moduleConfig.findActionConfigId(actionId);
        if (actionConfig == null) {
            if (log.isDebugEnabled()) {
                log.debug("No actionId found for " + actionId);
            }
            return null;
        }

        String path = actionConfig.getPath();
        String mapping = RequestUtils.getServletMapping(servlet);
        StringBuffer actionIdPath = new StringBuffer();

        // Form the path based on the servlet mapping pattern
        if (mapping.startsWith("*")) {
            actionIdPath.append(path);
            actionIdPath.append(mapping.substring(1));
        } else if (mapping.startsWith("/")) {  // implied ends with a *
            mapping = mapping.substring(0, mapping.length() - 1);
            if (mapping.endsWith("/") && path.startsWith("/")) {
                actionIdPath.append(mapping);
                actionIdPath.append(path.substring(1));
            } else {
                actionIdPath.append(mapping);
                actionIdPath.append(path);
            }
        } else {
            log.warn("Unknown servlet mapping pattern");
            actionIdPath.append(path);
        }

        // Lastly add any query parameters (the ? is part of the query string)
        if (qs != null) {
            actionIdPath.append(qs);
        }

        // Return the path
        if (log.isDebugEnabled()) {
            log.debug(originalPath + " unaliased to " + actionIdPath.toString());
        }
        return actionIdPath.toString();
    }

    /**
     * Verifies whether current request is forwarded from one action to
     * another or not.
     * @param request current HTTP request 
     * @return true if the request contains Globals.FORWARD_KEY, which means
     *         that request has been forwarded from another action.
     *
     * @since Struts 1.4
     */
    public static boolean isForwarded(HttpServletRequest request) {
        return request.getAttribute(Globals.FORWARD_KEY) != null;
    }
}