web.xml - Where is the right place for spring configuration files? -
why there must <init-param> in <servlet> node <param-name> "contextconfiglocation" ? because if comment <init-param> group project not load?
<?xml version="1.0" encoding="utf-8"?> <web-app xmlns:xsi="http://www.w3.org/2001/xmlschema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemalocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="webapp_id" version="3.0"> <display-name>archetype created web application</display-name> <!-- spring mvc dispatcher servlet --> <servlet> <servlet-name>mvc-dispatcher</servlet-name> <servlet-class>org.springframework.web.servlet.dispatcherservlet</servlet-class> <init-param> <param-name>contextconfiglocation</param-name> <param-value></param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>mvc-dispatcher</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> <listener> <listener-class>org.springframework.web.context.contextloaderlistener</listener-class> </listener> <!-- loads spring configurations files --> <context-param> <param-name>contextconfiglocation</param-name> <param-value> /web-inf/spring-mvc.xml, /web-inf/spring-security.xml, /web-inf/hibernate-context.xml </param-value> </context-param> <!-- spring security filter --> <filter> <filter-name>springsecurityfilterchain</filter-name> <filter-class>org.springframework.web.filter.delegatingfilterproxy</filter-class> </filter> <filter-mapping> <filter-name>springsecurityfilterchain</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> </web-app>
what right place spring configuration files ?
you can load spring configuration files either through <context-param> or <init-param> of servlet class. but, there difference explained below:
if loading using <context-param>, dependencies (spring beans) available whole application (for servlets). used load common dependencies across whole application (like services, daos, etc..).
but, if loading using <init-param> of dispatcherservlet, dependencies (spring beans) available dispatcherservlet child context. so, if have multiple entry end points application (like restlet or apache cxfservlet etc..), can maintain child contexts 1 per each servlet (entry point). each child context owns/loads specific dependencies respective web tier.
you can @ below notes taken spring's webapplicationcontext api:
like generic application contexts, web application contexts hierarchical. there single root context per application, while each servlet in application (including dispatcher servlet in mvc framework) has own child context.
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