org.springframework.web
Class SpringServletContainerInitializer

java.lang.Object
  org.springframework.web.SpringServletContainerInitializer

Servlet 3.0 ServletContainerInitializer designed to support code-based
 configuration of the servlet container using Spring's WebApplicationInitializer
 SPI as opposed to (or possibly in combination with) the traditional
 web.xml-based approach.

 
Mechanism of Operation
 This class will be loaded and instantiated and have its onStartup
 method invoked by any Servlet 3.0-compliant container during container startup assuming
 that the spring-web module JAR is present on the classpath. This occurs through
 the JAR Services API ServiceLoader.load(Class) method detecting the
 spring-web module's META-INF/services/javax.servlet.ServletContainerInitializer
 service provider configuration file. See the
 
 JAR Services API documentation as well as section 8.2.4 of the Servlet 3.0
 Final Draft specification for complete details.

 
when in combination with web.xml
 
If a web application does include a WEB-INF/web.xml file, it is important to
 understand that neither this nor any other ServletContextInitializer will be
 processed unless the <web-app> element's version attribute is >= "3.0"
 and the xsi:schemaLocation for "http://java.sun.com/xml/ns/javaee" is set to
 "http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd".

 
Relationship to Spring's WebApplicationInitializer
 Spring's WebApplicationInitializer SPI consists of just one method:
 WebApplicationInitializer.onStartup(ServletContext). The signature is intentionally
 quite similar to ServletContainerInitializer#onStartup(Set, ServletContext):
 simply put, SpringServletContainerInitializer is responsible for instantiating
 and delegating the ServletContext to any user-defined
 WebApplicationInitializer implementations. It is then the responsibility of
 each WebApplicationInitializer to do the actual work of initializing the
 ServletContext. The exact process of delegation is described in detail in the
 onStartup documentation below.

 
General Notes
 In general, this class should be viewed as supporting infrastructure for
 the more important and user-facing WebApplicationInitializer SPI. Taking
 advantage of this container initializer is also completely optional: while
 it is true that this initializer will be loaded and invoked under all Servlet 3.0+
 runtimes, it remains the user's choice whether to make any
 WebApplicationInitializer implementations available on the classpath. If no
 WebApplicationInitializer types are detected, this container initializer will
 have no effect.

 
Note that use of this container initializer and of WebApplicationInitializer
 is not in any way "tied" to Spring MVC other than the fact that the types are shipped
 in the spring-web module JAR. Rather, they can be considered general-purpose
 in their ability to facilitate convenient code-based configuration of the
 ServletContext. Said another way, any servlet, listener, or filter may be
 registered within a WebApplicationInitializer, not just Spring MVC-specific
 components.

 
This class is not designed for nor intended to be extended. It should be considered
 an internal type, with WebApplicationInitializer being the public-facing SPI.

 
See Also
 See WebApplicationInitializer Javadoc for examples and detailed usage
 recommendations.





Since:
  
3.1
Author:
  
Chris Beams, Juergen Hoeller
See Also:
onStartup(Set, ServletContext), 
WebApplicationInitializer