In Spring web mvc
1) If we define DispatcherServlet
as below
<servlet>
<servlet-name>appServlet</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
</servlet>
it looks for file named appServlet-servlet.xml
under WEB-INF
folder as mentioned in the spring reference.
My question is can we change this file name and location it looks for? (I think using context or init parameters we can do this,can any body tell me what exactly it should be?)
2) In every spring web mvc web.xml
,we will have the below line:
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
Here, My question is what context files it looks for? (is is this context loader listener which looks for disp开发者_运维百科atcherservlet-servlet.xml?)
3) Difference between dispatcherservlet-servlet.xml
and applicationcontext.xml
? (I saw some examples..where people are importing applicationcontext.xml
into dispatcherservlet-servlet.xml
?)
4) Please tell me how many contexts we can have for spring web and are there any naming conventions for this(like dispatcher servlet)?/
"The namespace can also be set explicitly via the
namespace
servlet init-param." You can set whatever path you want there, relative to the context rootNo, the
ContextLoaderListener
looks forapplicationContext.xml
(or for the file specified by the context-paramcontextConfigLocation
. Again the path is relative to the context-root. I usually place mine in/WEB-INF/classes/applicationContext.xml
, and set this as a value of the context-param).The
dispatcherServlet-servlet.xml
is a child context to the one defined byapplicationContext.xml
. The child context can access beans from the parent context, but the opposite is not true. So imagine you have a "web" context, with all controllers and web-related stuff, and a "main" context with everything elseIt is advisable to have as few contexts as possible (for the sake of simplicity). But you can define multiple dispatcher servlets, and hence have multiple "child" contexts.
My question is can we change this file name and location it looks for?
Did you mean that you want to use a file which is NOT named as appServlet.xml
Copying-pasting from mvc-shocase/web.xml
<!-- Processes application requests -->
<servlet>
<servlet-name>appServlet</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/spring/appServlet/servlet-context.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
1A)Yes, but we need to pass the init-param to the DispatcherServlet with name and value as "contextConfigLocation" and "location of ur file" respectively in DD or web.xml file.
2A)Bozho already answered. It[the ContextLoaderListener] looks to load the context xml file(s) provided as context param-value mapped to context param-name for the context-param. Looking for the "dispatcherservlet-servlet.xml" is a default process in Spring MVC. ContextLoaderListener don't looks for it.
3A)Bozho already answered.
4A)Bozho already answered.
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