Package org.springframework.web.context.support

Class WebApplicationContextUtils

java.lang.Object

org.springframework.web.context.support.WebApplicationContextUtils

public abstract class WebApplicationContextUtils
extends Object

Convenience methods for retrieving the root WebApplicationContext for a given ServletContext. This is useful for programmatically accessing a Spring application context from within custom web views or MVC actions.

Note that there are more convenient ways of accessing the root context for many web frameworks, either part of Spring or available as an external library. This helper class is just the most generic way to access the root context.

Author:

Juergen Hoeller

See Also:

• ContextLoader
• FrameworkServlet
• DispatcherServlet
• FacesContextUtils
• SpringBeanFacesELResolver

Constructor Summary

Constructors

Constructor	Description
WebApplicationContextUtils()

Method Summary

Modifier and Type	Method	Description
static WebApplicationContext	findWebApplicationContext(ServletContext sc)	Find a unique WebApplicationContext for this web app: either the root web app context (preferred) or a unique WebApplicationContext among the registered ServletContext attributes (typically coming from a single DispatcherServlet in the current web application).
static WebApplicationContext	getRequiredWebApplicationContext(ServletContext sc)	Find the root WebApplicationContext for this web app, typically loaded via ContextLoaderListener.
static WebApplicationContext	getWebApplicationContext(ServletContext sc)	Find the root WebApplicationContext for this web app, typically loaded via ContextLoaderListener.
static WebApplicationContext	getWebApplicationContext(ServletContext sc, String attrName)	Find a custom WebApplicationContext for this web app.
static void	initServletPropertySources(MutablePropertySources propertySources, ServletContext servletContext)	Convenient variant of initServletPropertySources(MutablePropertySources, ServletContext, ServletConfig) that always provides null for the ServletConfig parameter.
static void	initServletPropertySources(MutablePropertySources sources, ServletContext servletContext, ServletConfig servletConfig)	Replace Servlet-based stub property sources with actual instances populated with the given servletContext and servletConfig objects.
static void	registerEnvironmentBeans(ConfigurableListableBeanFactory bf, ServletContext sc)	Register web-specific environment beans ("contextParameters", "contextAttributes") with the given BeanFactory, as used by the WebApplicationContext.
static void	registerEnvironmentBeans(ConfigurableListableBeanFactory bf, ServletContext servletContext, ServletConfig servletConfig)	Register web-specific environment beans ("contextParameters", "contextAttributes") with the given BeanFactory, as used by the WebApplicationContext.
static void	registerWebApplicationScopes(ConfigurableListableBeanFactory beanFactory)	Register web-specific scopes ("request", "session", "globalSession") with the given BeanFactory, as used by the WebApplicationContext.
static void	registerWebApplicationScopes(ConfigurableListableBeanFactory beanFactory, ServletContext sc)	Register web-specific scopes ("request", "session", "globalSession", "application") with the given BeanFactory, as used by the WebApplicationContext.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

WebApplicationContextUtils

public WebApplicationContextUtils()

Method Details

getRequiredWebApplicationContext

public static WebApplicationContext getRequiredWebApplicationContext(ServletContext sc)
                                                              throws IllegalStateException

Find the root WebApplicationContext for this web app, typically loaded via ContextLoaderListener.

Will rethrow an exception that happened on root context startup, to differentiate between a failed context startup and no context at all.

Parameters:

sc - the ServletContext to find the web application context for

Returns:

the root WebApplicationContext for this web app

Throws:

IllegalStateException - if the root WebApplicationContext could not be found

See Also:

• WebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE

getWebApplicationContext

@Nullable
public static WebApplicationContext getWebApplicationContext(ServletContext sc)

Find the root WebApplicationContext for this web app, typically loaded via ContextLoaderListener.

Will rethrow an exception that happened on root context startup, to differentiate between a failed context startup and no context at all.

Parameters:

sc - the ServletContext to find the web application context for

Returns:

the root WebApplicationContext for this web app, or null if none

See Also:

• WebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE

getWebApplicationContext

@Nullable
public static WebApplicationContext getWebApplicationContext(ServletContext sc,
 String attrName)

Find a custom WebApplicationContext for this web app.

Parameters:

sc - the ServletContext to find the web application context for

attrName - the name of the ServletContext attribute to look for

Returns:

the desired WebApplicationContext for this web app, or null if none

findWebApplicationContext

@Nullable
public static WebApplicationContext findWebApplicationContext(ServletContext sc)

Find a unique WebApplicationContext for this web app: either the root web app context (preferred) or a unique WebApplicationContext among the registered ServletContext attributes (typically coming from a single DispatcherServlet in the current web application).

Note that DispatcherServlet's exposure of its context can be controlled through its publishContext property, which is true by default but can be selectively switched to only publish a single context despite multiple DispatcherServlet registrations in the web app.

Parameters:

sc - the ServletContext to find the web application context for

Returns:

the desired WebApplicationContext for this web app, or null if none

Since:

4.2

See Also:

• getWebApplicationContext(ServletContext)
• ServletContext.getAttributeNames()

registerWebApplicationScopes

public static void registerWebApplicationScopes(ConfigurableListableBeanFactory beanFactory)

Register web-specific scopes ("request", "session", "globalSession") with the given BeanFactory, as used by the WebApplicationContext.

Parameters:

beanFactory - the BeanFactory to configure

registerWebApplicationScopes

public static void registerWebApplicationScopes(ConfigurableListableBeanFactory beanFactory,
 @Nullable
 ServletContext sc)

Register web-specific scopes ("request", "session", "globalSession", "application") with the given BeanFactory, as used by the WebApplicationContext.

Parameters:

beanFactory - the BeanFactory to configure

sc - the ServletContext that we're running within

registerEnvironmentBeans

public static void registerEnvironmentBeans(ConfigurableListableBeanFactory bf,
 @Nullable
 ServletContext sc)

Register web-specific environment beans ("contextParameters", "contextAttributes") with the given BeanFactory, as used by the WebApplicationContext.

Parameters:

bf - the BeanFactory to configure

sc - the ServletContext that we're running within

registerEnvironmentBeans

public static void registerEnvironmentBeans(ConfigurableListableBeanFactory bf,
 @Nullable
 ServletContext servletContext,
 @Nullable
 ServletConfig servletConfig)

Register web-specific environment beans ("contextParameters", "contextAttributes") with the given BeanFactory, as used by the WebApplicationContext.

Parameters:

bf - the BeanFactory to configure

servletContext - the ServletContext that we're running within

servletConfig - the ServletConfig

initServletPropertySources

public static void initServletPropertySources(MutablePropertySources propertySources,
 ServletContext servletContext)

Convenient variant of initServletPropertySources(MutablePropertySources, ServletContext, ServletConfig) that always provides null for the ServletConfig parameter.

See Also:

• initServletPropertySources(MutablePropertySources, ServletContext, ServletConfig)

initServletPropertySources

public static void initServletPropertySources(MutablePropertySources sources,
 @Nullable
 ServletContext servletContext,
 @Nullable
 ServletConfig servletConfig)

Replace Servlet-based stub property sources with actual instances populated with the given servletContext and servletConfig objects.

This method is idempotent with respect to the fact it may be called any number of times but will perform replacement of stub property sources with their corresponding actual property sources once and only once.

Parameters:

sources - the MutablePropertySources to initialize (must not be null)

servletContext - the current ServletContext (ignored if null or if the servlet context property source has already been initialized)

servletConfig - the current ServletConfig (ignored if null or if the servlet config property source has already been initialized)

See Also:

• PropertySource.StubPropertySource
• ConfigurableEnvironment.getPropertySources()