org.springframework.web.servlet.mvc
Class ServletForwardingController

java.lang.Object
  org.springframework.context.support.ApplicationObjectSupport
      org.springframework.web.context.support.WebApplicationObjectSupport
          org.springframework.web.servlet.support.WebContentGenerator
              org.springframework.web.servlet.mvc.AbstractController
                  org.springframework.web.servlet.mvc.ServletForwardingController

All Implemented Interfaces:

BeanNameAware, ApplicationContextAware, ServletContextAware, Controller

public class ServletForwardingController
extends AbstractController
implements BeanNameAware

Spring Controller implementation that forwards to a named servlet, i.e. the "servlet-name" in web.xml rather than a URL path mapping. A target servlet doesn't even need a "servlet-mapping" in web.xml in the first place: A "servlet" declaration is sufficient.

Useful to invoke an existing servlet via Spring's dispatching infrastructure, for example to apply Spring HandlerInterceptors to its requests. This will work even in a Servlet 2.2 container that does not support Servlet filters.

In particular, the main intent of this controller is to allow for applying Spring's OpenSessionInViewInterceptor or OpenPersistenceManagerInViewInterceptor to servlets in a Servlet 2.2 container. The specified "servlet-name" will simply refer to a custom servlet definition in web.xml in such a scenario. You then need to map "/myservlet" (or whatever path you choose for your servlet) onto this controller, which will in turn forward to your servlet.

In a Servlet 2.3 container, when not using Spring's own web MVC framework, it is recommended to use classic servlet mapping in combination with a filter, for example Spring's OpenSessionInViewFilter or OpenPersistenceManagerInViewFilter.

Example: web.xml, mapping all "/myservlet" requests to a Spring dispatcher. Also defines a custom "myServlet", but without servlet mapping.

 <servlet>
   <servlet-name>myServlet</servlet-name>
   <servlet-class>mypackage.TestServlet</servlet-class>
 </servlet>

 <servlet>
   <servlet-name>myDispatcher</servlet-name>
   <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
 </servlet>

 <servlet-mapping>
   <servlet-name>myDispatcher</servlet-name>
   <url-pattern>/myservlet</url-pattern>
 </servlet-mapping>

Example: myDispatcher-servlet.xml, in turn forwarding "/myservlet" to your servlet (identified by servlet name). All such requests will go through the configured HandlerInterceptor chain (e.g. an OpenSessionInViewInterceptor). From the servlet point of view, everything will work as usual.

 <bean id="urlMapping" class="org.springframework.web.servlet.handler.SimpleUrlHandlerMapping">
   <property name="interceptors">
     <list>
       <ref bean="openSessionInViewInterceptor"/>
     </list>
   </property>
   <property name="mappings">
     <props>
       <prop key="/myservlet">myServletForwardingController</prop>
     </props>
   </property>
 </bean>

 <bean id="myServletForwardingController" class="org.springframework.web.servlet.mvc.ServletForwardingController">
   <property name="servletName"><value>myServlet</value></property>
 </bean>

Since:

1.1.1

Author:

Juergen Hoeller

See Also:

ServletWrappingController, OpenSessionInViewInterceptor, OpenSessionInViewFilter, OpenPersistenceManagerInViewInterceptor, OpenPersistenceManagerInViewFilter

Field Summary

Fields inherited from class org.springframework.web.servlet.support.WebContentGenerator

METHOD_GET, METHOD_HEAD, METHOD_POST

Fields inherited from class org.springframework.context.support.ApplicationObjectSupport

logger

Constructor Summary

ServletForwardingController()

Method Summary

protected ModelAndView	handleRequestInternal(HttpServletRequest request, HttpServletResponse response) Template method.
void	setBeanName(String name) Set the name of the bean in the bean factory that created this bean.
void	setServletName(String servletName) Set the name of the servlet to forward to, i.e. the "servlet-name" of the target servlet in web.xml.
protected boolean	useInclude(HttpServletRequest request, HttpServletResponse response) Determine whether to use RequestDispatcher's include or forward method.

Methods inherited from class org.springframework.web.servlet.mvc.AbstractController

handleRequest, isSynchronizeOnSession, setSynchronizeOnSession

Methods inherited from class org.springframework.web.servlet.support.WebContentGenerator

applyCacheSeconds, applyCacheSeconds, cacheForSeconds, cacheForSeconds, checkAndPrepare, checkAndPrepare, getCacheSeconds, getSupportedMethods, isRequireSession, isUseCacheControlHeader, isUseExpiresHeader, preventCaching, setCacheSeconds, setRequireSession, setSupportedMethods, setUseCacheControlHeader, setUseExpiresHeader

Methods inherited from class org.springframework.web.context.support.WebApplicationObjectSupport

getServletContext, getTempDir, getWebApplicationContext, isContextRequired, setServletContext

Methods inherited from class org.springframework.context.support.ApplicationObjectSupport

getApplicationContext, getMessageSourceAccessor, initApplicationContext, requiredContextClass, setApplicationContext

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ServletForwardingController

public ServletForwardingController()

Method Detail

setServletName

public void setServletName(String servletName)

Set the name of the servlet to forward to, i.e. the "servlet-name" of the target servlet in web.xml.

Default is the bean name of this controller.

setBeanName

public void setBeanName(String name)

Description copied from interface: BeanNameAware

Set the name of the bean in the bean factory that created this bean.

Invoked after population of normal bean properties but before an init callback such as InitializingBean.afterPropertiesSet() or a custom init-method.

Specified by:

setBeanName in interface BeanNameAware

Parameters:

name - the name of the bean in the factory. Note that this name is the actual bean name used in the factory, which may differ from the originally specified name: in particular for inner bean names, the actual bean name might have been made unique through appending "#..." suffixes. Use the BeanFactoryUtils.originalBeanName(String) method to extract the original bean name (without suffix), if desired.

handleRequestInternal

protected ModelAndView handleRequestInternal(HttpServletRequest request,
                                             HttpServletResponse response)
                                      throws Exception

Description copied from class: AbstractController

Template method. Subclasses must implement this. The contract is the same as for handleRequest.

Specified by:

handleRequestInternal in class AbstractController

Throws:

Exception

See Also:

AbstractController.handleRequest(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)

useInclude

protected boolean useInclude(HttpServletRequest request,
                             HttpServletResponse response)

Determine whether to use RequestDispatcher's include or forward method.

Performs a check whether an include URI attribute is found in the request, indicating an include request, and whether the response has already been committed. In both cases, an include will be performed, as a forward is not possible anymore.

Parameters:

request - current HTTP request

response - current HTTP response

Returns:

true for include, false for forward

See Also:

RequestDispatcher.forward(javax.servlet.ServletRequest, javax.servlet.ServletResponse), RequestDispatcher.include(javax.servlet.ServletRequest, javax.servlet.ServletResponse), ServletResponse.isCommitted(), WebUtils.isIncludeRequest(javax.servlet.ServletRequest)