org.springframework.web.method.annotation
Class SessionAttributesHandler

java.lang.Object
  org.springframework.web.method.annotation.SessionAttributesHandler

public class SessionAttributesHandler
extends java.lang.Object

Manages controller-specific session attributes declared via @SessionAttributes. Actual storage is performed via SessionAttributeStore.

When a controller annotated with @SessionAttributes adds attributes to its model, those attributes are checked against names and types specified via @SessionAttributes. Matching model attributes are saved in the HTTP session and remain there until the controller calls SessionStatus.setComplete().

Since:

3.1

Author:

Rossen Stoyanchev

Field Summary

private java.util.Set<java.lang.String>	attributeNames
private java.util.Set<java.lang.Class<?>>	attributeTypes
private java.util.Set<java.lang.String>	resolvedAttributeNames
private SessionAttributeStore	sessionAttributeStore

Constructor Summary

SessionAttributesHandler(java.lang.Class<?> handlerType, SessionAttributeStore sessionAttributeStore)
Creates a new instance for a controller type.

Method Summary

void	cleanupAttributes(WebRequest request) Cleans "known" attributes from the session - i.e.
boolean	hasSessionAttributes() Whether the controller represented by this instance has declared session attribute names or types of interest via SessionAttributes.
boolean	isHandlerSessionAttribute(java.lang.String attributeName, java.lang.Class<?> attributeType) Whether the attribute name and/or type match those specified in the controller's @SessionAttributes annotation.
(package private) java.lang.Object	retrieveAttribute(WebRequest request, java.lang.String attributeName) A pass-through call to the underlying SessionAttributeStore.
java.util.Map<java.lang.String,java.lang.Object>	retrieveAttributes(WebRequest request) Retrieve "known" attributes from the session -- i.e.
void	storeAttributes(WebRequest request, java.util.Map<java.lang.String,?> attributes) Stores a subset of the given attributes in the session.

Methods inherited from class java.lang.Object

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

Field Detail

attributeNames

private final java.util.Set<java.lang.String> attributeNames

attributeTypes

private final java.util.Set<java.lang.Class<?>> attributeTypes

resolvedAttributeNames

private final java.util.Set<java.lang.String> resolvedAttributeNames

sessionAttributeStore

private final SessionAttributeStore sessionAttributeStore

Constructor Detail

SessionAttributesHandler

public SessionAttributesHandler(java.lang.Class<?> handlerType,
                                SessionAttributeStore sessionAttributeStore)

Creates a new instance for a controller type. Session attribute names/types are extracted from a type-level @SessionAttributes if found.

Parameters:

handlerType - the controller type

sessionAttributeStore - used for session access

Method Detail

hasSessionAttributes

public boolean hasSessionAttributes()

Whether the controller represented by this instance has declared session attribute names or types of interest via SessionAttributes.

isHandlerSessionAttribute

public boolean isHandlerSessionAttribute(java.lang.String attributeName,
                                         java.lang.Class<?> attributeType)

Whether the attribute name and/or type match those specified in the controller's @SessionAttributes annotation.

Attributes successfully resolved through this method are "remembered" and used in retrieveAttributes(WebRequest) and cleanupAttributes(WebRequest). In other words, retrieval and cleanup only affect attributes previously resolved through here.

Parameters:

attributeName - the attribute name to check; must not be null

attributeType - the type for the attribute; or null

storeAttributes

public void storeAttributes(WebRequest request,
                            java.util.Map<java.lang.String,?> attributes)

Stores a subset of the given attributes in the session. Attributes not declared as session attributes via @SessionAttributes are ignored.

Parameters:

request - the current request

attributes - candidate attributes for session storage

retrieveAttributes

public java.util.Map<java.lang.String,java.lang.Object> retrieveAttributes(WebRequest request)

Retrieve "known" attributes from the session -- i.e. attributes listed in @SessionAttributes and previously stored in the in the model at least once.

Parameters:

request - the current request

Returns:

a map with handler session attributes; possibly empty.

cleanupAttributes

public void cleanupAttributes(WebRequest request)

Cleans "known" attributes from the session - i.e. attributes listed in @SessionAttributes and previously stored in the in the model at least once.

Parameters:

request - the current request

retrieveAttribute

java.lang.Object retrieveAttribute(WebRequest request,
                                   java.lang.String attributeName)

A pass-through call to the underlying SessionAttributeStore.

Parameters:

request - the current request

attributeName - the name of the attribute of interest

Returns:

the attribute value or null