dispatcherportlet.java

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	 * @return the corresponding LocaleContext
	 */
	protected LocaleContext buildLocaleContext(PortletRequest request) {
		return new SimpleLocaleContext(request.getLocale());
	}

	/**
	 * Convert the request into a multipart request, and make multipart resolver available.
	 * If no multipart resolver is set, simply use the existing request.
	 * @param request current HTTP request
	 * @return the processed request (multipart wrapper if necessary)
	 */
	protected ActionRequest checkMultipart(ActionRequest request) throws MultipartException {
		if (this.multipartResolver != null && this.multipartResolver.isMultipart(request)) {
			if (request instanceof MultipartActionRequest) {
				logger.debug("Request is already a MultipartActionRequest - probably in a forward");
			}
			else {
				return this.multipartResolver.resolveMultipart(request);
			}
		}
		// If not returned before: return original request.
		return request;
	}

	/**
	 * Return the HandlerExecutionChain for this request.
	 * Try all handler mappings in order.
	 * @param request current portlet request
	 * @param cache whether to cache the HandlerExecutionChain in a request attribute
	 * @return the HandlerExceutionChain, or null if no handler could be found
	 */
	protected HandlerExecutionChain getHandler(PortletRequest request, boolean cache) throws Exception {
		HandlerExecutionChain handler =
				(HandlerExecutionChain) request.getAttribute(HANDLER_EXECUTION_CHAIN_ATTRIBUTE);
		if (handler != null) {
			if (!cache) {
				request.removeAttribute(HANDLER_EXECUTION_CHAIN_ATTRIBUTE);
			}
			return handler;
		}

		Iterator it = this.handlerMappings.iterator();
		while (it.hasNext()) {
			HandlerMapping hm = (HandlerMapping) it.next();
			if (logger.isDebugEnabled()) {
				logger.debug("Testing handler map [" + hm + "] in DispatcherPortlet with name '" +
						getPortletName() + "'");
			}
			handler = hm.getHandler(request);
			if (handler != null) {
				if (cache) {
					request.setAttribute(HANDLER_EXECUTION_CHAIN_ATTRIBUTE, handler);
				}
				return handler;
			}
		}
		return null;
	}

	/**
	 * No handler found -> throw appropriate exception.
	 * @param request current portlet request
	 * @param response current portlet response
	 */
	protected void noHandlerFound(PortletRequest request, PortletResponse response) throws PortletException {
		if (pageNotFoundLogger.isWarnEnabled()) {
			pageNotFoundLogger.warn("No mapping found for current request " +
					"in DispatcherPortlet with name '" + getPortletName() + "'" +
					" mode '" + request.getPortletMode() + "'" +
					" type '" + (request instanceof ActionRequest ? "action" : "render") + "'" +
					" session '" + request.getRequestedSessionId() + "'" +
					" user '" + getUsernameForRequest(request) + "'");
		}
		throw new UnavailableException("No handler found for request");
	}

	/**
	 * Return the HandlerAdapter for this handler object.
	 * @param handler the handler object to find an adapter for
	 * @throws PortletException if no HandlerAdapter can be found for the handler.
	 * This is a fatal error.
	 */
	protected HandlerAdapter getHandlerAdapter(Object handler) throws PortletException {
		Iterator it = this.handlerAdapters.iterator();
		while (it.hasNext()) {
			HandlerAdapter ha = (HandlerAdapter) it.next();
			if (logger.isDebugEnabled()) {
				logger.debug("Testing handler adapter [" + ha + "]");
			}
			if (ha.supports(handler)) {
				return ha;
			}
		}
		throw new PortletException("No adapter for handler [" + handler +
				"]: Does your handler implement a supported interface like Controller?");
	}

	/**
	 * Determine an error ModelAndView via the registered HandlerExceptionResolvers.
	 * @param request current portlet request
	 * @param response current portlet response
	 * @param handler the executed handler, or null if none chosen at the time of
	 * the exception (for example, if multipart resolution failed)
	 * @param ex the exception that got thrown during handler execution
	 * @return a corresponding ModelAndView to forward to
	 * @throws Exception if no error ModelAndView found
	 */
	protected ModelAndView processHandlerException(
			RenderRequest request, RenderResponse response, Object handler, Exception ex)
			throws Exception {

		ModelAndView exMv = null;
		for (Iterator it = this.handlerExceptionResolvers.iterator(); exMv == null && it.hasNext();) {
			HandlerExceptionResolver resolver = (HandlerExceptionResolver) it.next();
			exMv = resolver.resolveException(request, response, handler, ex);
		}
		if (exMv != null) {
			if (logger.isDebugEnabled()) {
				logger.debug("HandlerExceptionResolver returned ModelAndView [" + exMv + "] for exception");
			}
			logger.warn("Handler execution resulted in exception - forwarding to resolved error view", ex);
			return exMv;
		}
		else {
			throw ex;
		}
	}

	/**
	 * Trigger afterCompletion callbacks on the mapped HandlerInterceptors.
	 * Will just invoke afterCompletion for all interceptors whose preHandle
	 * invocation has successfully completed and returned true.
	 * @param mappedHandler the mapped HandlerExecutionChain
	 * @param interceptorIndex index of last interceptor that successfully completed
	 * @param ex Exception thrown on handler execution, or null if none
	 * @see HandlerInterceptor#afterRenderCompletion
	 */
	private void triggerAfterActionCompletion(HandlerExecutionChain mappedHandler, int interceptorIndex,
			ActionRequest request, ActionResponse response, Exception ex)
			throws Exception {

		// Apply afterCompletion methods of registered interceptors.
		if (mappedHandler != null) {
			if (mappedHandler.getInterceptors() != null) {
				for (int i = interceptorIndex; i >= 0; i--) {
					HandlerInterceptor interceptor = mappedHandler.getInterceptors()[i];
					try {
						interceptor.afterActionCompletion(request, response, mappedHandler.getHandler(), ex);
					}
					catch (Throwable ex2) {
						logger.error("HandlerInterceptor.afterCompletion threw exception", ex2);
					}
				}
			}
		}
	}


	/**
	 * Render the given ModelAndView. This is the last stage in handling a request.
	 * It may involve resolving the view by name.
	 * @param mv the ModelAndView to render
	 * @param request current portlet render request
	 * @param response current portlet render response
	 * @throws Exception if there's a problem rendering the view
	 */
	protected void render(ModelAndView mv, RenderRequest request, RenderResponse response) throws Exception {
		View view = null;
		if (mv.isReference()) {
			// We need to resolve the view name.
			view = resolveViewName(mv.getViewName(), mv.getModelInternal(), request);
			if (view == null) {
				throw new PortletException("Could not resolve view with name '" + mv.getViewName() +
						"' in portlet with name '" + getPortletName() + "'");
			}
		}
		else {
			// No need to lookup: the ModelAndView object contains the actual View object.
			Object viewObject = mv.getView();
			if (viewObject == null) {
				throw new PortletException("ModelAndView [" + mv + "] neither contains a view name nor a " +
						"View object in portlet with name '" + getPortletName() + "'");
			}
			if (!(viewObject instanceof View)) {
				throw new PortletException(
						"View object [" + viewObject + "] is not an instance of [org.springframework.web.servlet.View] - " +
						"DispatcherPortlet does not support any other view types");
			}
			view = (View) viewObject;
		}

		if (view == null) {
			throw new PortletException("Could not resolve view with name '" + mv.getViewName() +
					"' in portlet with name '" + getPortletName() + "'");
		}

		// Set the content type on the response if needed and if possible.
		// The Portlet spec requires the content type to be set on the RenderResponse;
		// it's not sufficient to let the View set it on the ServletResponse.
		if (response.getContentType() != null) {
			if (logger.isDebugEnabled()) {
				logger.debug("Portlet response content type already set to [" + response.getContentType() + "]");
			}
		}
		else {
			// No Portlet content type specified yet -> use the view-determined type.
			String contentType = view.getContentType();
			if (contentType != null) {
				if (logger.isDebugEnabled()) {
					logger.debug("Setting portlet response content type to view-determined type [" + contentType + "]");
				}
				response.setContentType(contentType);
			}
		}

		// Expose Portlet ApplicationContext to view objects.
		request.setAttribute(ViewRendererServlet.WEB_APPLICATION_CONTEXT_ATTRIBUTE, getPortletApplicationContext());

		// These attributes are required by the ViewRendererServlet.
		request.setAttribute(ViewRendererServlet.VIEW_ATTRIBUTE, view);
		request.setAttribute(ViewRendererServlet.MODEL_ATTRIBUTE, mv.getModel());

		// Unclude the content of the view in the render response.
		getPortletContext().getRequestDispatcher(this.viewRendererUrl).include(request, response);
	}

	/**
	 * Resolve the given view name into a View object (to be rendered).
	 * <p>Default implementations asks all ViewResolvers of this dispatcher.
	 * Can be overridden for custom resolution strategies, potentially based
	 * on specific model attributes or request parameters.
	 * @param viewName the name of the view to resolve
	 * @param model the model to be passed to the view
	 * @param request current portlet render request
	 * @return the View object, or null if none found
	 * @throws Exception if the view cannot be resolved
	 * (typically in case of problems creating an actual View object)
	 * @see ViewResolver#resolveViewName
	 */
	protected View resolveViewName(String viewName, Map model, RenderRequest request) throws Exception {
		for (Iterator it = this.viewResolvers.iterator(); it.hasNext();) {
			ViewResolver viewResolver = (ViewResolver) it.next();
			View view = viewResolver.resolveViewName(viewName, request.getLocale());
			if (view != null) {
				return view;
			}
		}
		return null;
	}

	/**
	 * Trigger afterCompletion callbacks on the mapped HandlerInterceptors.
	 * Will just invoke afterCompletion for all interceptors whose preHandle
	 * invocation has successfully completed and returned true.
	 * @param mappedHandler the mapped HandlerExecutionChain
	 * @param interceptorIndex index of last interceptor that successfully completed
	 * @param ex Exception thrown on handler execution, or null if none
	 * @see HandlerInterceptor#afterRenderCompletion
	 */
	private void triggerAfterRenderCompletion(HandlerExecutionChain mappedHandler, int interceptorIndex,
			RenderRequest request, RenderResponse response, Exception ex)
			throws Exception {

		// Apply afterCompletion methods of registered interceptors.
		if (mappedHandler != null) {
			if (mappedHandler.getInterceptors() != null) {
				for (int i = interceptorIndex; i >= 0; i--) {
					HandlerInterceptor interceptor = mappedHandler.getInterceptors()[i];
					try {
						interceptor.afterRenderCompletion(request, response, mappedHandler.getHandler(), ex);
					}
					catch (Throwable ex2) {
						logger.error("HandlerInterceptor.afterCompletion threw exception", ex2);
					}
				}
			}
		}
	}

}