org.springframework.web.context.request

Class ServletRequestAttributes

java.lang.Object

org.springframework.web.context.request.AbstractRequestAttributes

org.springframework.web.context.request.ServletRequestAttributes

All Implemented Interfaces:

RequestAttributes

Direct Known Subclasses:

ServletWebRequest

public class ServletRequestAttributes
extends AbstractRequestAttributes

Servlet-based implementation of the RequestAttributes interface.

Accesses objects from servlet request and HTTP session scope, with no distinction between "session" and "global session".

Since:

2.0

Author:

Juergen Hoeller

See Also:

ServletRequest.getAttribute(java.lang.String), HttpSession.getAttribute(java.lang.String)

Field Summary

Fields

Modifier and Type	Field and Description
static String	DESTRUCTION_CALLBACK_NAME_PREFIX Constant identifying the String prefixed to the name of a destruction callback when it is stored in a HttpSession.
protected static Set<Class<?>>	immutableValueTypes

Fields inherited from class org.springframework.web.context.request.AbstractRequestAttributes

requestDestructionCallbacks

Fields inherited from interface org.springframework.web.context.request.RequestAttributes

REFERENCE_REQUEST, REFERENCE_SESSION, SCOPE_REQUEST, SCOPE_SESSION

Constructor Summary

Constructors

Constructor and Description
ServletRequestAttributes(HttpServletRequest request) Create a new ServletRequestAttributes instance for the given request.
ServletRequestAttributes(HttpServletRequest request, HttpServletResponse response) Create a new ServletRequestAttributes instance for the given request.

Method Summary

Modifier and Type	Method and Description
Object	getAttribute(String name, int scope) Return the value for the scoped attribute of the given name, if any.
String[]	getAttributeNames(int scope) Retrieve the names of all attributes in the scope.
HttpServletRequest	getRequest() Exposes the native HttpServletRequest that we're wrapping.
HttpServletResponse	getResponse() Exposes the native HttpServletResponse that we're wrapping (if any).
protected HttpSession	getSession(boolean allowCreate) Exposes the HttpSession that we're wrapping.
String	getSessionId() Return an id for the current underlying session.
Object	getSessionMutex() Expose the best available mutex for the underlying session: that is, an object to synchronize on for the underlying session.
protected boolean	isImmutableSessionAttribute(String name, Object value) Determine whether the given value is to be considered as an immutable session attribute, that is, doesn't have to be re-set via session.setAttribute since its value cannot meaningfully change internally.
void	registerDestructionCallback(String name, Runnable callback, int scope) Register a callback to be executed on destruction of the specified attribute in the given scope.
protected void	registerSessionDestructionCallback(String name, Runnable callback) Register the given callback as to be executed after session termination.
void	removeAttribute(String name, int scope) Remove the scoped attribute of the given name, if it exists.
Object	resolveReference(String key) Resolve the contextual reference for the given key, if any.
void	setAttribute(String name, Object value, int scope) Set the value for the scoped attribute of the given name, replacing an existing value (if any).
String	toString()
protected void	updateAccessedSessionAttributes() Update all accessed session attributes through session.setAttribute calls, explicitly indicating to the container that they might have been modified.

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

isRequestActive, registerRequestDestructionCallback, removeRequestDestructionCallback, requestCompleted

Methods inherited from class java.lang.Object

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

Field Detail

DESTRUCTION_CALLBACK_NAME_PREFIX

public static final String DESTRUCTION_CALLBACK_NAME_PREFIX

Constant identifying the String prefixed to the name of a destruction callback when it is stored in a HttpSession.

immutableValueTypes

protected static final Set<Class<?>> immutableValueTypes

Constructor Detail

ServletRequestAttributes

public ServletRequestAttributes(HttpServletRequest request)

Create a new ServletRequestAttributes instance for the given request.

Parameters:

request - current HTTP request

ServletRequestAttributes

public ServletRequestAttributes(HttpServletRequest request,
                                @Nullable
                                HttpServletResponse response)

Create a new ServletRequestAttributes instance for the given request.

Parameters:

request - current HTTP request

response - current HTTP response (for optional exposure)

Method Detail

getRequest

public final HttpServletRequest getRequest()

Exposes the native HttpServletRequest that we're wrapping.

getResponse

@Nullable
public final HttpServletResponse getResponse()

Exposes the native HttpServletResponse that we're wrapping (if any).

getSession

@Nullable
protected final HttpSession getSession(boolean allowCreate)

Exposes the HttpSession that we're wrapping.

Parameters:

allowCreate - whether to allow creation of a new session if none exists yet

getAttribute

public Object getAttribute(String name,
                           int scope)

Description copied from interface: RequestAttributes

Return the value for the scoped attribute of the given name, if any.

Parameters:

name - the name of the attribute

scope - the scope identifier

Returns:

the current attribute value, or null if not found

setAttribute

public void setAttribute(String name,
                         Object value,
                         int scope)

Description copied from interface: RequestAttributes

Set the value for the scoped attribute of the given name, replacing an existing value (if any).

Parameters:

name - the name of the attribute

value - the value for the attribute

scope - the scope identifier

removeAttribute

public void removeAttribute(String name,
                            int scope)

Description copied from interface: RequestAttributes

Remove the scoped attribute of the given name, if it exists.

Note that an implementation should also remove a registered destruction callback for the specified attribute, 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).

Parameters:

name - the name of the attribute

scope - the scope identifier

getAttributeNames

public String[] getAttributeNames(int scope)

Description copied from interface: RequestAttributes

Retrieve the names of all attributes in the scope.

Parameters:

scope - the scope identifier

Returns:

the attribute names as String array

registerDestructionCallback

public void registerDestructionCallback(String name,
                                        Runnable callback,
                                        int scope)

Description copied from interface: RequestAttributes

Register a callback to be executed on destruction of the specified attribute in the given scope.

Implementations should do their best to execute the callback at the appropriate time: that is, at request completion or session termination, respectively. If such a callback is not supported by the underlying runtime environment, the callback must be ignored and a corresponding warning should be logged.

Note that 'destruction' usually corresponds to destruction of the entire scope, not to the individual attribute having been explicitly removed by the application. If an attribute gets removed via this facade's RequestAttributes.removeAttribute(String, int) method, any registered destruction callback should be disabled as well, assuming that the removed object will be reused or manually destroyed.

NOTE: Callback objects should generally be serializable if they are being registered for a session scope. Otherwise the callback (or even the entire session) might not survive web app restarts.

Parameters:

name - the name of the attribute to register the callback for

callback - the destruction callback to be executed

scope - the scope identifier

resolveReference

public Object resolveReference(String key)

Description copied from interface: RequestAttributes

Resolve the contextual reference for the given key, if any.

At a minimum: the HttpServletRequest reference for key "request", and the HttpSession reference for key "session".

Parameters:

key - the contextual key

Returns:

the corresponding object, or null if none found

getSessionId

public String getSessionId()

Description copied from interface: RequestAttributes

Return an id for the current underlying session.

Returns:

the session id as String (never null)

getSessionMutex

public Object getSessionMutex()

Description copied from interface: RequestAttributes

Expose the best available mutex for the underlying session: that is, an object to synchronize on for the underlying session.

Returns:

the session mutex to use (never null)

updateAccessedSessionAttributes

protected void updateAccessedSessionAttributes()

Update all accessed session attributes through session.setAttribute calls, explicitly indicating to the container that they might have been modified.

Specified by:

updateAccessedSessionAttributes in class AbstractRequestAttributes

isImmutableSessionAttribute

protected boolean isImmutableSessionAttribute(String name,
                                              @Nullable
                                              Object value)

Determine whether the given value is to be considered as an immutable session attribute, that is, doesn't have to be re-set via session.setAttribute since its value cannot meaningfully change internally.

The default implementation returns true for String, Character, Boolean and standard Number values.

Parameters:

name - the name of the attribute

value - the corresponding value to check

Returns:

true if the value is to be considered as immutable for the purposes of session attribute management; false otherwise

See Also:

updateAccessedSessionAttributes()

registerSessionDestructionCallback

protected void registerSessionDestructionCallback(String name,
                                                  Runnable callback)

Register the given callback as to be executed after session termination.

Note: The callback object should be serializable in order to survive web app restarts.

Parameters:

name - the name of the attribute to register the callback for

callback - the callback to be executed for destruction

toString

public String toString()

Overrides:

toString in class Object