Package com.google.gwt.storage.client

Class StorageImpl

java.lang.Object

com.google.gwt.storage.client.StorageImpl

Direct Known Subclasses:

StorageImplNonNativeEvents

class StorageImpl
extends Object

This is the HTML5 Storage implementation according to the standard recommendation.

Never use this class directly, instead use Storage.

See Also:

• W3C Web Storage - Storage

Field Summary

Fields

Modifier and Type	Field	Description
protected static JavaScriptObject	jsHandler
static final String	LOCAL_STORAGE
static final String	SESSION_STORAGE
protected static List<StorageEvent.Handler>	storageEventHandlers

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	StorageImpl()	This class can never be instantiated by itself.

Method Summary

Modifier and Type	Method	Description
HandlerRegistration	addStorageEventHandler(StorageEvent.Handler handler)	Registers an event handler for StorageEvents.
protected void	addStorageEventHandler0()
void	clear(String storage)	Removes all items in the Storage.
String	getItem(String storage, String key)	Returns the item in the Storage associated with the specified key.
int	getLength(String storage)	Returns the number of items in this Storage.
protected List<StorageEvent.Handler>	getStorageEventHandlers()	Returns the List of StorageEvent.Handlers registered, which is never null.
protected Storage	getStorageFromEvent(StorageEvent event)	Returns the Storage object that was affected in the event.
protected static final void	handleStorageEvent(StorageEvent event)	Handles StorageEvents if a StorageEvent.Handler is registered.
protected static boolean	hasStorageEventHandlers()	Returns true if at least one StorageEvent handler is registered, false otherwise.
String	key(String storage, int index)	Returns the key at the specified index.
void	removeItem(String storage, String key)	Removes the item in the Storage associated with the specified key.
void	removeStorageEventHandler(StorageEvent.Handler handler)	De-registers an event handler for StorageEvents.
protected void	removeStorageEventHandler0()
void	setItem(String storage, String key, String data)	Sets the value in the Storage associated with the specified key to the specified data.

Methods inherited from class java.lang.Object

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

Field Details

LOCAL_STORAGE

public static final String LOCAL_STORAGE

See Also:

• Constant Field Values

SESSION_STORAGE

public static final String SESSION_STORAGE

See Also:

• Constant Field Values

storageEventHandlers

protected static List<StorageEvent.Handler> storageEventHandlers

jsHandler

protected static JavaScriptObject jsHandler

Constructor Details

StorageImpl

protected StorageImpl()

This class can never be instantiated by itself.

Method Details

handleStorageEvent

protected static final void handleStorageEvent(StorageEvent event)

Handles StorageEvents if a StorageEvent.Handler is registered.

hasStorageEventHandlers

protected static boolean hasStorageEventHandlers()

Returns true if at least one StorageEvent handler is registered, false otherwise.

addStorageEventHandler

public HandlerRegistration addStorageEventHandler(StorageEvent.Handler handler)

Registers an event handler for StorageEvents.

Parameters:

handler -

Returns:

HandlerRegistration used to remove this handler

See Also:

• W3C Web Storage - the storage event

clear

public void clear(String storage)

Removes all items in the Storage.

Parameters:

storage - either LOCAL_STORAGE or SESSION_STORAGE

See Also:

• W3C Web Storage - Storage.clear()

getItem

public String getItem(String storage,
 String key)

Returns the item in the Storage associated with the specified key.

Parameters:

storage - either LOCAL_STORAGE or SESSION_STORAGE

key - the key to a value in the Storage

Returns:

the value associated with the given key

See Also:

• W3C Web Storage - Storage.getItem(k)

getLength

public int getLength(String storage)

Returns the number of items in this Storage.

Parameters:

storage - either LOCAL_STORAGE or SESSION_STORAGE

Returns:

number of items in this Storage

See Also:

• W3C Web Storage - Storage.length()

key

public String key(String storage,
 int index)

Returns the key at the specified index.

Parameters:

storage - either LOCAL_STORAGE or SESSION_STORAGE

index - the index of the key

Returns:

the key at the specified index in this Storage

See Also:

• W3C Web Storage - Storage.key(n)

removeItem

public void removeItem(String storage,
 String key)

Removes the item in the Storage associated with the specified key.

Parameters:

storage - either LOCAL_STORAGE or SESSION_STORAGE

key - the key to a value in the Storage

See Also:

• W3C Web Storage - Storage.removeItem(k)

removeStorageEventHandler

public void removeStorageEventHandler(StorageEvent.Handler handler)

De-registers an event handler for StorageEvents.

Parameters:

handler -

See Also:

• W3C Web Storage - the storage event

setItem

public void setItem(String storage,
 String key,
 String data)

Sets the value in the Storage associated with the specified key to the specified data.

Parameters:

storage - either LOCAL_STORAGE or SESSION_STORAGE

key - the key to a value in the Storage

data - the value associated with the key

See Also:

• W3C Web Storage - Storage.setItem(k,v)

addStorageEventHandler0

protected void addStorageEventHandler0()

getStorageEventHandlers

protected List<StorageEvent.Handler> getStorageEventHandlers()

Returns the List of StorageEvent.Handlers registered, which is never null.

getStorageFromEvent

protected Storage getStorageFromEvent(StorageEvent event)

Returns the Storage object that was affected in the event.

Returns:

the Storage object that was affected in the event.

removeStorageEventHandler0

protected void removeStorageEventHandler0()