How Spring loads spring configuration files ?

[Prabhat Ranjan]

Hi,

I have Spring web application which contains basic steps
1) Web.xml file where we configure DispatcherServlet

<web-app> <servlet>
<servlet-name>test</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>test</servlet-name>
<url-pattern>*.do</url-pattern>
</servlet-mapping>
</web-app>

where i found one configuration file test-servlet.xml .

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd">

<!--
  - Application context definition for "springapp" DispatcherServlet.
  -->

<beans>
<bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="viewClass" value="org.springframework.web.servlet.view.JstlView"/>
<property name="prefix" value="/WEB-INF/jsp/"/>
<property name="suffix" value=".jsp"/>
</bean>
</beans>

But i very curious about how & when this file is getting loaded into the web-container.

there is no defination for this file any where in web-xml ...

is i am missing anything , please update !

[Ashwin Sridhar]

Hi,

When the server is started, the web.xml file is loaded. The Dispatcher servlet registered helps to find out the xml file.
It searches for xml file with name <servlet-name>-servlet.xml and loads it.

[Prabhat Ranjan]

yes correct thanks !

I was confused like contextLoaderLister and ApplicationContext.xml files getting loaded as it is configured same way !

again thanks !

any good toutrial on spring , please let me know !

[Mark Spritzler]

Prabhat Ranjan wrote:yes correct thanks !

I was confused like contextLoaderLister and ApplicationContext.xml files getting loaded as it is configured same way !

again thanks !

any good toutrial on spring , please let me know !

Yes and no. Sort of. Basically the DispatcherServlet creates an ApplicationContext, but really should only contain the beans for the Web Layer, no middle tier beans. So for the middle tier beans are loaded via the ContextLoaderListener which creates its own ApplicationContext.

So typically you end up with two ApplicationContexts. One for the middle tier and one for the web layer. Where the web layer beans can have the middle tier beans injected into them.

Mark

[Prabhat Ranjan]

can we give example for both the middle tier beans and web beans , as web beans i know probably and middle tier beans means non-web spring application.

is it like that ?

[Mark Spritzler]

Prabhat Ranjan wrote:can we give example for both the middle tier beans and web beans , as web beans i know probably and middle tier beans means non-web spring application.

is it like that ?

Yes, If I had a Spring MVC app, the web beans are my Controllers, ViewResolvers and MappingHandlers. The middle tier are my Services, Repositoryies, TransactionManager, DataSource, etc.

Mark