Loading context in Spring using web.xml

JavaSpring Mvcweb.xml

Java Problem Overview


Is there a way that a context can be loaded using web.xml in a Spring MVC application?

Java Solutions


Solution 1 - Java

From the spring docs

Spring can be easily integrated into any Java-based web framework. All you need to do is to declare the ContextLoaderListener in your web.xml and use a contextConfigLocation to set which context files to load.

The <context-param>:

<context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>/WEB-INF/applicationContext*.xml</param-value>
</context-param>

<listener>
   <listener-class>
        org.springframework.web.context.ContextLoaderListener
   </listener-class>
</listener> 

You can then use the WebApplicationContext to get a handle on your beans.

WebApplicationContext ctx = WebApplicationContextUtils.getRequiredWebApplicationContext(servlet.getServletContext());
SomeBean someBean = (SomeBean) ctx.getBean("someBean");

See http://static.springsource.org/spring/docs/2.5.x/api/org/springframework/web/context/support/WebApplicationContextUtils.html for more info

Solution 2 - Java

You can also specify context location relatively to current classpath, which may be preferable

<context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>classpath*:applicationContext*.xml</param-value>
</context-param>

<listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>

Solution 3 - Java

You can also load the context while defining the servlet itself (WebApplicationContext)

  <servlet>
    <servlet-name>admin</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>
				/WEB-INF/spring/*.xml
			</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
  </servlet>
  <servlet-mapping>
    <servlet-name>admin</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>

rather than (ApplicationContext)

<context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>/WEB-INF/applicationContext*.xml</param-value>
</context-param>

<listener>
   <listener-class>
        org.springframework.web.context.ContextLoaderListener
   </listener-class>
</listener> 

or can do both together.

Drawback of just using WebApplicationContext is that it will load context only for this particular Spring entry point (DispatcherServlet) where as with above mentioned methods context will be loaded for multiple entry points (Eg. Webservice Servlet, REST servlet etc)

Context loaded by ContextLoaderListener will infact be a parent context to that loaded specifically for DisplacherServlet . So basically you can load all your business service, data access or repository beans in application context and separate out your controller, view resolver beans to WebApplicationContext.

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Content TypeOriginal AuthorOriginal Content on Stackoverflow
QuestionGaneshView Question on Stackoverflow
Solution 1 - JavaddewaeleView Answer on Stackoverflow
Solution 2 - JavafmucarView Answer on Stackoverflow
Solution 3 - JavaAniket ThakurView Answer on Stackoverflow