Class ServletContextScope
- All Implemented Interfaces:
Scope, DisposableBean
Scope
wrapper for a ServletContext, i.e. for global web application attributes.
This differs from traditional Spring singletons in that it exposes attributes in the ServletContext. Those attributes will get destroyed whenever the entire application shuts down, which might be earlier or later than the shutdown of the containing Spring ApplicationContext.
The associated destruction mechanism relies on a
ContextCleanupListener
being registered in
web.xml
. Note that ContextLoaderListener
includes ContextCleanupListener's functionality.
This scope is registered as default scope with key
"application"
.
- Since:
- 3.0
- Author:
- Juergen Hoeller
- See Also:
-
Constructor Summary
ConstructorsConstructorDescriptionServletContextScope
(ServletContext servletContext) Create a new Scope wrapper for the given ServletContext. -
Method Summary
Modifier and TypeMethodDescriptionvoid
destroy()
Invoke all registered destruction callbacks.get
(String name, ObjectFactory<?> objectFactory) Return the object with the given name from the underlying scope,creating it
if not found in the underlying storage mechanism.void
registerDestructionCallback
(String name, Runnable callback) Register a callback to be executed on destruction of the specified object in the scope (or at destruction of the entire scope, if the scope does not destroy individual objects but rather only terminates in its entirety).Remove the object with the givenname
from the underlying scope.Methods inherited from class Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Methods inherited from interface Scope
getConversationId, resolveContextualObject
-
Constructor Details
-
ServletContextScope
Create a new Scope wrapper for the given ServletContext.- Parameters:
servletContext
- the ServletContext to wrap
-
-
Method Details
-
get
Description copied from interface:Scope
Return the object with the given name from the underlying scope,creating it
if not found in the underlying storage mechanism.This is the central operation of a Scope, and the only operation that is absolutely required.
- Specified by:
get
in interfaceScope
- Parameters:
name
- the name of the object to retrieveobjectFactory
- theObjectFactory
to use to create the scoped object if it is not present in the underlying storage mechanism- Returns:
- the desired object (never
null
)
-
remove
Description copied from interface:Scope
Remove the object with the givenname
from the underlying scope.Returns
null
if no object was found; otherwise returns the removedObject
.Note that an implementation should also remove a registered destruction callback for the specified object, if any. It does, however, not need to execute a registered destruction callback in this case, since the object will be destroyed by the caller (if appropriate).
Note: This is an optional operation. Implementations may throw
UnsupportedOperationException
if they do not support explicitly removing an object. -
registerDestructionCallback
Description copied from interface:Scope
Register a callback to be executed on destruction of the specified object in the scope (or at destruction of the entire scope, if the scope does not destroy individual objects but rather only terminates in its entirety).Note: This is an optional operation. This method will only be called for scoped beans with actual destruction configuration (DisposableBean, destroy-method, DestructionAwareBeanPostProcessor). Implementations should do their best to execute a given callback at the appropriate time. If such a callback is not supported by the underlying runtime environment at all, the callback must be ignored and a corresponding warning should be logged.
Note that 'destruction' refers to automatic destruction of the object as part of the scope's own lifecycle, not to the individual scoped object having been explicitly removed by the application. If a scoped object gets removed via this facade's
Scope.remove(String)
method, any registered destruction callback should be removed as well, assuming that the removed object will be reused or manually destroyed.- Specified by:
registerDestructionCallback
in interfaceScope
- Parameters:
name
- the name of the object to execute the destruction callback forcallback
- the destruction callback to be executed. Note that the passed-in Runnable will never throw an exception, so it can safely be executed without an enclosing try-catch block. Furthermore, the Runnable will usually be serializable, provided that its target object is serializable as well.- See Also:
-
destroy
public void destroy()Invoke all registered destruction callbacks. To be called on ServletContext shutdown.- Specified by:
destroy
in interfaceDisposableBean
- See Also:
-