Where to put default-servlet-handler in Spring MVC configuration
- by gigadot
In my web.xml, the default servlet mapping, i.e. /, is mapped to Spring dispatcher. In my Spring dispatcher configuration, I have DefaultAnnotationHandlerMapping, ControllerClassNameHandlerMapping and AnnotationMethodHandlerAdapter which allows me to map url to controllers either by its class name or its @Requestmapping annotation. However, there are some static resources under the web root which I also want spring dispatcher to serve using default servlet. According to Spring documentation, this can be done using <mvc:default-servlet-handler/> tag.
In the configuration below, there are 4 candidate locations that I marked which are possible to insert this tag. Inserting the tag in different location causes the dispatcher to behave differently as following :
Case 1 : If I insert it at location 1, the dispatcher will no longer be able to handle mapping by the @RequestMapping and controller class name but it will be serving the static content normally.
Cas 2, 3 : It will be able to handle mapping by the @RequestMapping and controller class name as well as serving the static content if other mapping cannot be done successfully.
Case 4 : It will not be able to serve the static contents.
Therefore, Case 2 and 3 are desirable .According to Spring documentation, this tag configures a handler which precedence order is given to lowest so why the position matters? and Which is the best position to put this tag?
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd">
<context:annotation-config/>
<context:component-scan base-package="webapp.controller"/>
<!-- Location 1 -->
<!-- Enable annotation-based controllers using @Controller annotations -->
<bean id="annotationUrlMapping" class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping"/>
<!-- Location 2 -->
<bean id="controllerClassNameHandlerMapping" class="org.springframework.web.servlet.mvc.support.ControllerClassNameHandlerMapping"/>
<!-- Location 3 -->
<bean id="annotationMethodHandlerAdapter" class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"/>
<!-- Location 4 -->
<mvc:default-servlet-handler/>
<!-- All views are JSPs loaded from /WEB-INF/jsp -->
<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>
