org.springframework.web.portlet.util
Class PortletUtils

java.lang.Object
  org.springframework.web.portlet.util.PortletUtils

public abstract class PortletUtils
extends Object

Miscellaneous utilities for portlet applications. Used by various framework classes.

Since:

2.0

Author:

Juergen Hoeller, William G. Thompson, Jr., John A. Lewis

Constructor Summary

PortletUtils()

Method Summary

static void	clearAllRenderParameters(ActionResponse response) Clear all the render parameters from the ActionResponse.
static void	exposeRequestAttributes(PortletRequest request, Map<String,?> attributes) Expose the given Map as request attributes, using the keys as attribute names and the values as corresponding attribute values.
static Cookie	getCookie(PortletRequest request, String name) Retrieve the first cookie with the given name.
static <T> T	getNativeRequest(PortletRequest request, Class<T> requiredType) Return an appropriate request object of the specified type, if available, unwrapping the given request as far as necessary.
static <T> T	getNativeResponse(PortletResponse response, Class<T> requiredType) Return an appropriate response object of the specified type, if available, unwrapping the given response as far as necessary.
static Object	getOrCreateSessionAttribute(PortletSession session, String name, Class clazz) Get the specified session attribute under the PortletSession.PORTLET_SCOPE, creating and setting a new attribute if no existing found.
static Object	getOrCreateSessionAttribute(PortletSession session, String name, Class clazz, int scope) Get the specified session attribute in the given scope, creating and setting a new attribute if no existing found.
static Map<String,Object>	getParametersStartingWith(PortletRequest request, String prefix) Return a map containing all parameters with the given prefix.
static String	getRealPath(PortletContext portletContext, String path) Return the real path of the given path within the web application, as provided by the portlet container.
static Object	getRequiredSessionAttribute(PortletRequest request, String name) Check the given request for a session attribute of the given name under the PortletSession.PORTLET_SCOPE.
static Object	getRequiredSessionAttribute(PortletRequest request, String name, int scope) Check the given request for a session attribute of the given name in the given scope.
static Object	getSessionAttribute(PortletRequest request, String name) Check the given request for a session attribute of the given name under the PortletSession.PORTLET_SCOPE.
static Object	getSessionAttribute(PortletRequest request, String name, int scope) Check the given request for a session attribute of the given name in the given scope.
static Object	getSessionMutex(PortletSession session) Return the best available mutex for the given session: that is, an object to synchronize on for the given session.
static String	getSubmitParameter(PortletRequest request, String name) Return the full name of a specific input type="submit" parameter if it was sent in the request, either via a button (directly with name) or via an image (name + ".x" or name + ".y").
static int	getTargetPage(PortletRequest request, String paramPrefix, int currentPage) Return the target page specified in the request.
static File	getTempDir(PortletContext portletContext) Return the temporary directory for the current web application, as provided by the portlet container.
static boolean	hasSubmitParameter(PortletRequest request, String name) Check if a specific input type="submit" parameter was sent in the request, either via a button (directly with name) or via an image (name + ".x" or name + ".y").
static void	passAllParametersToRenderPhase(ActionRequest request, ActionResponse response) Pass all the action request parameters to the render phase by putting them into the action response object.
static void	serveResource(ResourceRequest request, ResourceResponse response, PortletContext context) Serve the resource as specified in the given request to the given response, using the PortletContext's request dispatcher.
static void	setSessionAttribute(PortletRequest request, String name, Object value) Set the session attribute with the given name to the given value under the PortletSession.PORTLET_SCOPE.
static void	setSessionAttribute(PortletRequest request, String name, Object value, int scope) Set the session attribute with the given name to the given value in the given scope.

Methods inherited from class java.lang.Object

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

Constructor Detail

PortletUtils

public PortletUtils()

Method Detail

getTempDir

public static File getTempDir(PortletContext portletContext)

Return the temporary directory for the current web application, as provided by the portlet container.

Parameters:

portletContext - the portlet context of the web application

Returns:

the File representing the temporary directory

getRealPath

public static String getRealPath(PortletContext portletContext,
                                 String path)
                          throws FileNotFoundException

Return the real path of the given path within the web application, as provided by the portlet container.

Prepends a slash if the path does not already start with a slash, and throws a FileNotFoundException if the path cannot be resolved to a resource (in contrast to PortletContext's getRealPath, which simply returns null).

Parameters:

portletContext - the portlet context of the web application

path - the relative path within the web application

Returns:

the corresponding real path

Throws:

FileNotFoundException - if the path cannot be resolved to a resource

See Also:

PortletContext.getRealPath(java.lang.String)

getSessionAttribute

public static Object getSessionAttribute(PortletRequest request,
                                         String name)

Check the given request for a session attribute of the given name under the PortletSession.PORTLET_SCOPE. Returns null if there is no session or if the session has no such attribute in that scope. Does not create a new session if none has existed before!

Parameters:

request - current portlet request

name - the name of the session attribute

Returns:

the value of the session attribute, or null if not found

getSessionAttribute

public static Object getSessionAttribute(PortletRequest request,
                                         String name,
                                         int scope)

Check the given request for a session attribute of the given name in the given scope. Returns null if there is no session or if the session has no such attribute in that scope. Does not create a new session if none has existed before!

Parameters:

request - current portlet request

name - the name of the session attribute

scope - session scope of this attribute

Returns:

the value of the session attribute, or null if not found

getRequiredSessionAttribute

public static Object getRequiredSessionAttribute(PortletRequest request,
                                                 String name)
                                          throws IllegalStateException

Check the given request for a session attribute of the given name under the PortletSession.PORTLET_SCOPE. Throws an exception if there is no session or if the session has no such attribute in that scope.

Does not create a new session if none has existed before!

Parameters:

request - current portlet request

name - the name of the session attribute

Returns:

the value of the session attribute

Throws:

IllegalStateException - if the session attribute could not be found

getRequiredSessionAttribute

public static Object getRequiredSessionAttribute(PortletRequest request,
                                                 String name,
                                                 int scope)
                                          throws IllegalStateException

Check the given request for a session attribute of the given name in the given scope. Throws an exception if there is no session or if the session has no such attribute in that scope.

Does not create a new session if none has existed before!

Parameters:

request - current portlet request

name - the name of the session attribute

scope - session scope of this attribute

Returns:

the value of the session attribute

Throws:

IllegalStateException - if the session attribute could not be found

setSessionAttribute

public static void setSessionAttribute(PortletRequest request,
                                       String name,
                                       Object value)

Set the session attribute with the given name to the given value under the PortletSession.PORTLET_SCOPE. Removes the session attribute if value is null, if a session existed at all. Does not create a new session if not necessary!

Parameters:

request - current portlet request

name - the name of the session attribute

value - the value of the session attribute

setSessionAttribute

public static void setSessionAttribute(PortletRequest request,
                                       String name,
                                       Object value,
                                       int scope)

Set the session attribute with the given name to the given value in the given scope. Removes the session attribute if value is null, if a session existed at all. Does not create a new session if not necessary!

Parameters:

request - current portlet request

name - the name of the session attribute

value - the value of the session attribute

scope - session scope of this attribute

getOrCreateSessionAttribute

public static Object getOrCreateSessionAttribute(PortletSession session,
                                                 String name,
                                                 Class clazz)
                                          throws IllegalArgumentException

Get the specified session attribute under the PortletSession.PORTLET_SCOPE, creating and setting a new attribute if no existing found. The given class needs to have a public no-arg constructor. Useful for on-demand state objects in a web tier, like shopping carts.

Parameters:

session - current portlet session

name - the name of the session attribute

clazz - the class to instantiate for a new attribute

Returns:

the value of the session attribute, newly created if not found

Throws:

IllegalArgumentException - if the session attribute could not be instantiated

getOrCreateSessionAttribute

public static Object getOrCreateSessionAttribute(PortletSession session,
                                                 String name,
                                                 Class clazz,
                                                 int scope)
                                          throws IllegalArgumentException

Get the specified session attribute in the given scope, creating and setting a new attribute if no existing found. The given class needs to have a public no-arg constructor. Useful for on-demand state objects in a web tier, like shopping carts.

Parameters:

session - current portlet session

name - the name of the session attribute

clazz - the class to instantiate for a new attribute

scope - the session scope of this attribute

Returns:

the value of the session attribute, newly created if not found

Throws:

IllegalArgumentException - if the session attribute could not be instantiated

getSessionMutex

public static Object getSessionMutex(PortletSession session)

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

Returns the session mutex attribute if available; usually, this means that the HttpSessionMutexListener needs to be defined in web.xml. Falls back to the PortletSession itself if no mutex attribute found.

The session mutex is guaranteed to be the same object during the entire lifetime of the session, available under the key defined by the WebUtils.SESSION_MUTEX_ATTRIBUTE constant. It serves as a safe reference to synchronize on for locking on the current session.

In many cases, the PortletSession reference itself is a safe mutex as well, since it will always be the same object reference for the same active logical session. However, this is not guaranteed across different servlet containers; the only 100% safe way is a session mutex.

Parameters:

session - the HttpSession to find a mutex for

Returns:

the mutex object (never null)

See Also:

WebUtils.SESSION_MUTEX_ATTRIBUTE, HttpSessionMutexListener

getNativeRequest

public static <T> T getNativeRequest(PortletRequest request,
                                     Class<T> requiredType)

Return an appropriate request object of the specified type, if available, unwrapping the given request as far as necessary.

Parameters:

request - the portlet request to introspect

requiredType - the desired type of request object

Returns:

the matching request object, or null if none of that type is available

getNativeResponse

public static <T> T getNativeResponse(PortletResponse response,
                                      Class<T> requiredType)

Return an appropriate response object of the specified type, if available, unwrapping the given response as far as necessary.

Parameters:

response - the portlet response to introspect

requiredType - the desired type of response object

Returns:

the matching response object, or null if none of that type is available

exposeRequestAttributes

public static void exposeRequestAttributes(PortletRequest request,
                                           Map<String,?> attributes)

Expose the given Map as request attributes, using the keys as attribute names and the values as corresponding attribute values. Keys must be Strings.

Parameters:

request - current portlet request

attributes - the attributes Map

getCookie

public static Cookie getCookie(PortletRequest request,
                               String name)

Retrieve the first cookie with the given name. Note that multiple cookies can have the same name but different paths or domains.

Parameters:

request - current portlet request

name - cookie name

Returns:

the first cookie with the given name, or null if none is found

hasSubmitParameter

public static boolean hasSubmitParameter(PortletRequest request,
                                         String name)

Check if a specific input type="submit" parameter was sent in the request, either via a button (directly with name) or via an image (name + ".x" or name + ".y").

Parameters:

request - current portlet request

name - name of the parameter

Returns:

if the parameter was sent

See Also:

WebUtils.SUBMIT_IMAGE_SUFFIXES

getSubmitParameter

public static String getSubmitParameter(PortletRequest request,
                                        String name)

Return the full name of a specific input type="submit" parameter if it was sent in the request, either via a button (directly with name) or via an image (name + ".x" or name + ".y").

Parameters:

request - current portlet request

name - name of the parameter

Returns:

the actual parameter name with suffix if needed - null if not present

See Also:

WebUtils.SUBMIT_IMAGE_SUFFIXES

getParametersStartingWith

public static Map<String,Object> getParametersStartingWith(PortletRequest request,
                                                           String prefix)

Return a map containing all parameters with the given prefix. Maps single values to String and multiple values to String array.

For example, with a prefix of "spring_", "spring_param1" and "spring_param2" result in a Map with "param1" and "param2" as keys.

Similar to portlet PortletRequest.getParameterMap(), but more flexible.

Parameters:

request - portlet request in which to look for parameters

prefix - the beginning of parameter names (if this is null or the empty string, all parameters will match)

Returns:

map containing request parameters without the prefix, containing either a String or a String array as values

See Also:

PortletRequest.getParameterNames(), PortletRequest.getParameterValues(java.lang.String), PortletRequest.getParameterMap()

getTargetPage

public static int getTargetPage(PortletRequest request,
                                String paramPrefix,
                                int currentPage)

Return the target page specified in the request.

Parameters:

request - current portlet request

paramPrefix - the parameter prefix to check for (e.g. "_target" for parameters like "_target1" or "_target2")

currentPage - the current page, to be returned as fallback if no target page specified

Returns:

the page specified in the request, or current page if not found

passAllParametersToRenderPhase

public static void passAllParametersToRenderPhase(ActionRequest request,
                                                  ActionResponse response)

Pass all the action request parameters to the render phase by putting them into the action response object. This may not be called when the action will call sendRedirect.

Parameters:

request - the current action request

response - the current action response

See Also:

StateAwareResponse.setRenderParameter(java.lang.String, java.lang.String)

clearAllRenderParameters

public static void clearAllRenderParameters(ActionResponse response)

Clear all the render parameters from the ActionResponse. This may not be called when the action will call sendRedirect.

Parameters:

response - the current action response

See Also:

StateAwareResponse.setRenderParameters(java.util.Map)

serveResource

public static void serveResource(ResourceRequest request,
                                 ResourceResponse response,
                                 PortletContext context)
                          throws PortletException,
                                 IOException

Serve the resource as specified in the given request to the given response, using the PortletContext's request dispatcher.

This is roughly equivalent to Portlet 2.0 GenericPortlet.

Parameters:

request - the current resource request

response - the current resource response

context - the current Portlet's PortletContext

Throws:

PortletException - propagated from Portlet API's forward method

IOException - propagated from Portlet API's forward method