org.apache.wicket.pageStore

Class AsynchronousPageStore

java.lang.Object

org.apache.wicket.pageStore.AsynchronousPageStore

All Implemented Interfaces:

IPageStore

public class AsynchronousPageStore
extends Object
implements IPageStore

Facade for IPageStore that does the actual saving in worker thread.

Creates an Entry for each double (sessionId, page) and puts it in entries queue if there is room. Acts as producer.
Later PageSavingRunnable reads in blocking manner from entries and saves each entry. Acts as consumer.

It starts only one instance of PageSavingRunnable because all we need is to make the page storing asynchronous. We don't want to write concurrently in the wrapped IPageStore, though it may happen in the extreme case when the queue is full. These cases should be avoided. Based on AsynchronousDataStore (@author Matej Knopp).

Author:

manuelbarzi

Constructor Summary

Constructors

Constructor and Description
AsynchronousPageStore(IPageStore delegate, int capacity) Construct.

Method Summary

Modifier and Type	Method and Description
boolean	canBeAsynchronous()
IManageablePage	convertToPage(Object page) Converts a page representation to an instance of IManageablePage
void	destroy() Destroy the store.
IManageablePage	getPage(String sessionId, int pageId) Restores a page from the persistent layer.
Serializable	prepareForSerialization(String sessionId, Serializable page) Process the page before the it gets serialized.
void	removePage(String sessionId, int pageId) Removes a page from the persistent layer.
Object	restoreAfterSerialization(Serializable serializable) This method should restore the serialized page to intermediate object that can be converted to real page instance using IPageStore.convertToPage(Object).
void	storePage(String sessionId, IManageablePage page) Stores the page to a persistent layer.
void	unbind(String sessionId) The page store should cleanup all the pages for that sessionid.

Methods inherited from class java.lang.Object

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

Constructor Detail

AsynchronousPageStore

public AsynchronousPageStore(IPageStore delegate,
                             int capacity)

Construct.

Parameters:

delegate - the wrapped IPageStore that actually saved the page

capacity - the capacity of the queue that delays the saving

Method Detail

destroy

public void destroy()

Description copied from interface: IPageStore

Destroy the store.

Specified by:

destroy in interface IPageStore

getPage

public IManageablePage getPage(String sessionId,
                               int pageId)

Description copied from interface: IPageStore

Restores a page from the persistent layer.

Specified by:

getPage in interface IPageStore

Parameters:

sessionId - The session of the page that must be removed

pageId - The id of the page.

Returns:

The page

removePage

public void removePage(String sessionId,
                       int pageId)

Description copied from interface: IPageStore

Removes a page from the persistent layer.

Specified by:

removePage in interface IPageStore

Parameters:

sessionId - The session of the page that must be removed

pageId - The id of the page.

storePage

public void storePage(String sessionId,
                      IManageablePage page)

Description copied from interface: IPageStore

Stores the page to a persistent layer. The page should be stored under the id and the version number.

Specified by:

storePage in interface IPageStore

Parameters:

sessionId - The session of the page that must be removed

page - The page to store

unbind

public void unbind(String sessionId)

Description copied from interface: IPageStore

The page store should cleanup all the pages for that sessionid.

Specified by:

unbind in interface IPageStore

Parameters:

sessionId - The session of the page that must be removed

prepareForSerialization

public Serializable prepareForSerialization(String sessionId,
                                            Serializable page)

Description copied from interface: IPageStore

Process the page before the it gets serialized. The page can be either real page instance or object returned by IPageStore.restoreAfterSerialization(Serializable).

Specified by:

prepareForSerialization in interface IPageStore

Parameters:

sessionId - The session of the page that must be removed

Returns:

The Page itself or a SerializedContainer for that page

restoreAfterSerialization

public Object restoreAfterSerialization(Serializable serializable)

Description copied from interface: IPageStore

This method should restore the serialized page to intermediate object that can be converted to real page instance using IPageStore.convertToPage(Object).

Specified by:

restoreAfterSerialization in interface IPageStore

Returns:

Page

convertToPage

public IManageablePage convertToPage(Object page)

Description copied from interface: IPageStore

Converts a page representation to an instance of IManageablePage

Specified by:

convertToPage in interface IPageStore

Parameters:

page - some kind of page representation

Returns:

page

canBeAsynchronous

public boolean canBeAsynchronous()

Specified by:

canBeAsynchronous in interface IPageStore

Returns:

whether the implementation can be wrapped in AsynchronousPageStore