Storage (Google Web Toolkit Javadoc)

java.lang.Object
- com.google.gwt.storage.client.Storage

```
public final class Storage
extends java.lang.Object
```
Implements the HTML5 Storage interface.
You can obtain a Storage by either invoking getLocalStorageIfSupported() or getSessionStorageIfSupported().

Experimental API: This API is still under development and is subject to change.

If Web Storage is NOT supported in the browser, these methods return null.

Note: Storage events into other windows are not supported.

This may not be supported on all browsers.

See Also:
W3C Web Storage - Storage, Safari Client-Side Storage and Offline Applications Programming Guide - Key-Value Storage, Quirksmode.org - HTML5 Compatibility - Storage, Wiki - Quickstart Guide

Field Summary

Fields
Modifier and Type Field and Description

(package private) static StorageImpl impl

Fields
Modifier and Type	Field and Description
`(package private) static StorageImpl`	`impl`

Method Summary

Methods
Modifier and Type	Method and Description
`static HandlerRegistration`	`addStorageEventHandler(StorageEvent.Handler handler)` Registers an event handler for StorageEvents.
`void`	`clear()` Removes all items in the Storage.
`java.lang.String`	`getItem(java.lang.String key)` Returns the item in the Storage associated with the specified key.
`int`	`getLength()` Returns the number of items in this Storage.
`static Storage`	`getLocalStorageIfSupported()` Returns a Local Storage.
`static Storage`	`getSessionStorageIfSupported()` Returns a Session Storage.
`static boolean`	`isLocalStorageSupported()` Returns `true` if the `localStorage` part of the Storage API is supported on the running platform.
`static boolean`	`isSessionStorageSupported()` Returns `true` if the `sessionStorage` part of the Storage API is supported on the running platform.
`static boolean`	`isSupported()` Returns `true` if the Storage API (both localStorage and sessionStorage) is supported on the running platform.
`java.lang.String`	`key(int index)` Returns the key at the specified index.
`void`	`removeItem(java.lang.String key)` Removes the item in the Storage associated with the specified key.
`static void`	`removeStorageEventHandler(StorageEvent.Handler handler)` De-registers an event handler for StorageEvents.
`void`	`setItem(java.lang.String key, java.lang.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 Detail
  - impl
```
static final StorageImpl impl
```
- Method Detail
  - addStorageEventHandler
```
public static 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
  - getLocalStorageIfSupported
```
public static Storage getLocalStorageIfSupported()
```
    Returns a Local Storage.
    The returned storage is associated with the origin of the Document.
    
    Returns:
    the localStorage instance, or null if Web Storage is NOT supported.
    See Also:
    W3C Web Storage - localStorage
  - getSessionStorageIfSupported
```
public static Storage getSessionStorageIfSupported()
```
    Returns a Session Storage.
    The returned storage is associated with the current top-level browsing context.
    
    Returns:
    the sessionStorage instance, or null if Web Storage is NOT supported.
    See Also:
    W3C Web Storage - sessionStorage
  - isLocalStorageSupported
```
public static boolean isLocalStorageSupported()
```
    Returns true if the localStorage part of the Storage API is supported on the running platform.
  - isSessionStorageSupported
```
public static boolean isSessionStorageSupported()
```
    Returns true if the sessionStorage part of the Storage API is supported on the running platform.
  - isSupported
```
public static boolean isSupported()
```
    Returns true if the Storage API (both localStorage and sessionStorage) is supported on the running platform.
  - removeStorageEventHandler
```
public static void removeStorageEventHandler(StorageEvent.Handler handler)
```
    De-registers an event handler for StorageEvents.
    
    Parameters:
    handler -
    See Also:
    W3C Web Storage - the storage event
  - clear
```
public void clear()
```
    Removes all items in the Storage.
    
    See Also:
    W3C Web Storage - Storage.clear()
  - getItem
```
public java.lang.String getItem(java.lang.String key)
```
    Returns the item in the Storage associated with the specified key.
    
    Parameters:
    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()
```
    Returns the number of items in this Storage.
    
    Returns:
    number of items in this Storage
    See Also:
    W3C Web Storage - Storage.length()
  - key
```
public java.lang.String key(int index)
```
    Returns the key at the specified index.
    
    Parameters:
    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(java.lang.String key)
```
    Removes the item in the Storage associated with the specified key.
    
    Parameters:
    key - the key to a value in the Storage
    See Also:
    W3C Web Storage - Storage.removeItem(k)
  - setItem
```
public void setItem(java.lang.String key,
           java.lang.String data)
```
    Sets the value in the Storage associated with the specified key to the specified data. Note: The empty string may not be used as a key.
    
    Parameters:
    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)

Class Storage

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

impl

Method Detail

addStorageEventHandler

getLocalStorageIfSupported

getSessionStorageIfSupported

isLocalStorageSupported

isSessionStorageSupported

isSupported

removeStorageEventHandler

clear

getItem

getLength

key

removeItem

setItem