org.apache.wicket.pageStore

Class AsynchronousDataStore

java.lang.Object

org.apache.wicket.pageStore.AsynchronousDataStore

All Implemented Interfaces:

IDataStore

public class AsynchronousDataStore
extends Object
implements IDataStore

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

Creates an Entry for each triple (sessionId, pageId, data) 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 IDataStore, though it may happen in the extreme case when the queue is full. These cases should be avoided.

Author:

Matej Knopp

Constructor Summary

Constructors

Constructor and Description
AsynchronousDataStore(IDataStore dataStore, int capacity) Construct.

Method Summary

Modifier and Type	Method and Description
boolean	canBeAsynchronous()
void	destroy() Properly close the data store and possibly open resource handles
byte[]	getData(String sessionId, int id) Get data associated with the session id and page id.
boolean	isReplicated()
void	removeData(String sessionId) Remove all page data for the session id
void	removeData(String sessionId, int id) Remove all persisted data related to the session id and page id
void	storeData(String sessionId, int id, byte[] data) Save the entry in the queue if there is a room or directly pass it to the wrapped IDataStore if there is no such

Methods inherited from class java.lang.Object

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

Constructor Detail

AsynchronousDataStore

public AsynchronousDataStore(IDataStore dataStore,
                             int capacity)

Construct.

Parameters:

dataStore - the wrapped IDataStore that actually saved the data

capacity - the capacity of the queue that delays the saving

Method Detail

destroy

public void destroy()

Description copied from interface: IDataStore

Properly close the data store and possibly open resource handles

Specified by:

destroy in interface IDataStore

getData

public byte[] getData(String sessionId,
                      int id)

Description copied from interface: IDataStore

Get data associated with the session id and page id.

Specified by:

getData in interface IDataStore

Parameters:

sessionId - Session ID

id - Page ID

Returns:

All the page data persisted

isReplicated

public boolean isReplicated()

Specified by:

isReplicated in interface IDataStore

Returns:

whether the data store is replicated

removeData

public void removeData(String sessionId,
                       int id)

Description copied from interface: IDataStore

Remove all persisted data related to the session id and page id

Specified by:

removeData in interface IDataStore

Parameters:

sessionId - Session ID

id - Page ID

removeData

public void removeData(String sessionId)

Description copied from interface: IDataStore

Remove all page data for the session id

Specified by:

removeData in interface IDataStore

Parameters:

sessionId - Session ID

storeData

public void storeData(String sessionId,
                      int id,
                      byte[] data)

Save the entry in the queue if there is a room or directly pass it to the wrapped IDataStore if there is no such

Specified by:

storeData in interface IDataStore

Parameters:

sessionId - Session ID

id - Page ID

data - Page data

See Also:

IDataStore.storeData(java.lang.String, int, byte[])

canBeAsynchronous

public final boolean canBeAsynchronous()

Specified by:

canBeAsynchronous in interface IDataStore

Returns:

whether the implementation can be wrapped in AsynchronousDataStore