org.springframework.web.context.request
Class SessionScope

java.lang.Object
  org.springframework.web.context.request.AbstractRequestAttributesScope
      org.springframework.web.context.request.SessionScope

All Implemented Interfaces:

Scope

public class SessionScope
extends AbstractRequestAttributesScope

Session-backed Scope implementation.

Relies on a thread-bound RequestAttributes instance, which can be exported through RequestContextListener, RequestContextFilter or DispatcherServlet.

This Scope will also work for Portlet environments, through an alternate RequestAttributes implementation (as exposed out-of-the-box by Spring's DispatcherPortlet.

Since:

2.0

Author:

Rod Johnson, Juergen Hoeller, Rob Harrop

See Also:

RequestContextHolder.currentRequestAttributes(), RequestAttributes.SCOPE_SESSION, RequestAttributes.SCOPE_GLOBAL_SESSION, RequestContextListener, RequestContextFilter, DispatcherServlet, DispatcherPortlet

Constructor Summary

SessionScope()
Create a new SessionScope, storing attributes in a locally isolated session (or default session, if there is no distinction between a global session and a component-specific session).

SessionScope(boolean globalSession)
Create a new SessionScope, specifying whether to store attributes in the global session, provided that such a distinction is available.

Method Summary

Object	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.
String	getConversationId() Return the conversation ID for the current underlying scope, if any.
protected int	getScope() Template method that determines the actual target scope.
Object	remove(String name) Remove the object with the given name from the underlying scope.

Methods inherited from class org.springframework.web.context.request.AbstractRequestAttributesScope

registerDestructionCallback, resolveContextualObject

Methods inherited from class java.lang.Object

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

Constructor Detail

SessionScope

public SessionScope()

Create a new SessionScope, storing attributes in a locally isolated session (or default session, if there is no distinction between a global session and a component-specific session).

SessionScope

public SessionScope(boolean globalSession)

Create a new SessionScope, specifying whether to store attributes in the global session, provided that such a distinction is available.

This distinction is important for Portlet environments, where there are two notions of a session: "portlet scope" and "application scope". If this flag is on, objects will be put into the "application scope" session; else they will end up in the "portlet scope" session (the typical default).

In a Servlet environment, this flag is effectively ignored.

Parameters:

globalSession - true in case of the global session as target; false in case of a component-specific session as target

See Also:

PortletRequestAttributes, ServletRequestAttributes

Method Detail

getScope

protected int getScope()

Description copied from class: AbstractRequestAttributesScope

Template method that determines the actual target scope.

Specified by:

getScope in class AbstractRequestAttributesScope

Returns:

the target scope, in the form of an appropriate RequestAttributes constant

See Also:

RequestAttributes.SCOPE_REQUEST, RequestAttributes.SCOPE_SESSION, RequestAttributes.SCOPE_GLOBAL_SESSION

getConversationId

public String getConversationId()

Description copied from interface: Scope

Return the conversation ID for the current underlying scope, if any.

The exact meaning of the conversation ID depends on the underlying storage mechanism. In the case of session-scoped objects, the conversation ID would typically be equal to (or derived from) the session ID; in the case of a custom conversation that sits within the overall session, the specific ID for the current conversation would be appropriate.

Note: This is an optional operation. It is perfectly valid to return null in an implementation of this method if the underlying storage mechanism has no obvious candidate for such an ID.

Returns:

the conversation ID, or null if there is no conversation ID for the current scope

get

public Object get(String name,
                  ObjectFactory objectFactory)

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 interface Scope

Overrides:

get in class AbstractRequestAttributesScope

Parameters:

name - the name of the object to retrieve

objectFactory - the ObjectFactory to use to create the scoped object if it is not present in the underlying storage mechanism

Returns:

the desired object (never null)

remove

public Object remove(String name)

Description copied from interface: Scope

Remove the object with the given name from the underlying scope.

Returns null if no object was found; otherwise returns the removed Object.

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.

Specified by:

remove in interface Scope

Overrides:

remove in class AbstractRequestAttributesScope

Parameters:

name - the name of the object to remove

Returns:

the removed object, or null if no object was present

See Also:

Scope.registerDestructionCallback(java.lang.String, java.lang.Runnable)