actioncontextbase.java.svn-base

MVC开源框架

    public void saveMessages(ActionMessages messages) {
        this.saveActionMessages(MESSAGE_ACTION_MESSAGES_KEY, messages);
    }

    // ISSUE: do we want to add this to the public API?

    /**
     * <p> Add the given messages to a cache stored in this Context, under
     * key. </p>
     *
     * @param key      The attribute name for the message cache
     * @param messages The ActionMessages to add
     */
    public void addActionMessages(String key, ActionMessages messages) {
        if (messages == null) {
            // bad programmer! *slap*
            return;
        }

        // get any existing messages from the request, or make a new one
        ActionMessages requestMessages = (ActionMessages) this.get(key);

        if (requestMessages == null) {
            requestMessages = new ActionMessages();
        }

        // add incoming messages
        requestMessages.add(messages);

        // if still empty, just wipe it out from the request
        this.remove(key);

        // save the messages
        this.saveActionMessages(key, requestMessages);
    }

    // ISSUE: do we want to add this to the public API?

    /**
     * <p> Save the given ActionMessages into the request scope under the
     * given key, clearing the attribute if the messages are empty or null.
     * </p>
     *
     * @param key      The attribute name for the message cache
     * @param messages The ActionMessages to add
     */
    public void saveActionMessages(String key, ActionMessages messages) {
        this.saveActionMessages(REQUEST_SCOPE, key, messages);
    }

    /**
     * <p>Save the given <code>messages</code> into the map identified by the
     * given <code>scopeId</code> under the given <code>key</code>.</p>
     *
     * @param scopeId
     * @param key
     * @param messages
     */
    public void saveActionMessages(String scopeId, String key,
        ActionMessages messages) {
        Map scope = getScope(scopeId);

        if ((messages == null) || messages.isEmpty()) {
            scope.remove(key);

            return;
        }

        scope.put(key, messages);
    }

    // ISSUE: Should we deprecate this method, since it is misleading?
    // Do we need it for backward compatibility?

    /**
     * <p> Adapt a legacy form of SaveMessages to the ActionContext API by
     * storing the ActoinMessages under the default scope.
     *
     * @param scope    The scope for the internal cache
     * @param messages ActionMesssages to cache
     */
    public void saveMessages(String scope, ActionMessages messages) {
        this.saveMessages(messages);
    }

    // -------------------------------
    // Token Processing
    // -------------------------------
    // ISSUE: Should there be a getToken method?
    // Is there a problem trying to map this method from Action
    // to ActionContext when we aren't necessarily sure how token
    // processing maps into a context with an ill-defined "session"?
    // There's no getToken() method, but maybe there should be. *
    public void saveToken() {
        String token = this.generateToken();

        this.put(TRANSACTION_TOKEN_KEY, token);
    }

    public String generateToken() {
        return token.generateToken(getTokenGeneratorId());
    }

    // ISSUE: The original implementation was based on the HttpSession
    // identifier; what would be a way to do that without depending on the
    // Servlet API?
    // REPLY: uuid's
    // http://java.sun.com/products/jini/2.0/doc/specs/api/net/jini/id/Uuid.html
    protected String getTokenGeneratorId() {
        return "";
    }

    public boolean isTokenValid() {
        return this.isTokenValid(false);
    }

    public boolean isTokenValid(boolean reset) {
        // Retrieve the transaction token from this session, and
        // reset it if requested
        String saved = (String) this.get(TRANSACTION_TOKEN_KEY);

        if (saved == null) {
            return false;
        }

        if (reset) {
            this.resetToken();
        }

        // Retrieve the transaction token included in this request
        String token = (String) this.get(TOKEN_KEY);

        if (token == null) {
            return false;
        }

        return saved.equals(token);
    }

    public void resetToken() {
        this.remove(TRANSACTION_TOKEN_KEY);
    }

    // -------------------------------
    // Cancel Processing
    // -------------------------------
    public Boolean getCancelled() {
        return (Boolean) this.get(CANCEL_KEY);
    }

    public void setCancelled(Boolean cancelled) {
        this.put(CANCEL_KEY, cancelled);
    }

    // -------------------------------
    // MessageResources Processing
    // -------------------------------
    public void setMessageResources(MessageResources messageResources) {
        this.put(MESSAGE_RESOURCES_KEY, messageResources);
    }

    public MessageResources getMessageResources() {
        return (MessageResources) this.get(MESSAGE_RESOURCES_KEY);
    }

    public MessageResources getMessageResources(String key) {
        return (MessageResources) this.get(key);
    }

    // -------------------------------
    // Locale Processing
    // -------------------------------
    public void setLocale(Locale locale) {
        this.put(LOCALE_KEY, locale);
    }

    public Locale getLocale() {
        return (Locale) this.get(LOCALE_KEY);
    }

    // -------------------------------
    // Convenience Methods: these are not part of the formal ActionContext API,
    // but are likely to be commonly useful.
    // -------------------------------

    /**
     * <p> Provide the currently configured commons-logging <code>Log</code>
     * instance. </p>
     *
     * @return Log instance for this context
     */
    public Log getLogger() {
        return this.logger;
    }

    /**
     * <p> Set the commons-logging <code>Log</code> instance which should be
     * used to LOG messages. This is initialized at instantiation time but may
     * be overridden. Be advised not to set the value to null, as
     * <code>ActionContextBase</code> uses the logger for some of its own
     * operations. </p>
     */
    public void setLogger(Log logger) {
        this.logger = logger;
    }

    /**
     * <p> Using this <code>ActionContext</code>'s default
     * <code>ModuleConfig</code>, return an existing <code>ActionForm</code>
     * in the specified scope, or create a new one and add it to the specified
     * scope. </p>
     *
     * @param formName  The name attribute of our ActionForm
     * @param scopeName The scope identier (request, session)
     * @return The ActionForm for this request
     * @throws IllegalAccessException If object cannot be created
     * @throws InstantiationException If object cannot be created
     * @see this.findOrCreateActionForm(String, String, ModuleConfig)
     */
    public ActionForm findOrCreateActionForm(String formName, String scopeName)
        throws IllegalAccessException, InstantiationException {
        return this.findOrCreateActionForm(formName, scopeName,
            this.getModuleConfig());
    }

    /**
     * <p> In the context of the given <code>ModuleConfig</code> and this
     * <code>ActionContext</code>, look for an existing
     * <code>ActionForm</code> in the specified scope. If one is found, return
     * it; otherwise, create a new instance, add it to that scope, and then
     * return it. </p>
     *
     * @param formName  The name attribute of our ActionForm
     * @param scopeName The scope identier (request, session)
     * @return The ActionForm for this request
     * @throws IllegalAccessException   If object cannot be created
     * @throws InstantiationException   If object cannot be created
     * @throws IllegalArgumentException If form config is missing from module
     *                                  or scopeName is invalid
     */
    public ActionForm findOrCreateActionForm(String formName, String scopeName,
        ModuleConfig moduleConfig)
        throws IllegalAccessException, InstantiationException {
        Map scope = this.getScope(scopeName);

        ActionForm instance;
        FormBeanConfig formBeanConfig =
            moduleConfig.findFormBeanConfig(formName);

        if (formBeanConfig == null) {
            throw new IllegalArgumentException("No form config found under "
                + formName + " in module " + moduleConfig.getPrefix());
        }

        instance = (ActionForm) scope.get(formName);

        // ISSUE: Can we recycle the existing instance (if any)?
        if (instance != null) {
            getLogger().trace("Found an instance in scope " + scopeName
                + "; test for reusability");

            if (formBeanConfig.canReuse(instance)) {
                return instance;
            }
        }

        ActionForm form = formBeanConfig.createActionForm(this);

        // ISSUE: Should we check this call to put?
        scope.put(formName, form);

        return form;
    }
}