public class WebStorage extends Object
WebView
. It manages the Application Cache API, the Web SQL Database
API and the HTML5 Web Storage API.
The Application Cache API provides a mechanism to create and maintain an
application cache to power offline Web applications. Use of the Application
Cache API can be attributed to an origin WebStorage.Origin
, however
it is not possible to set per-origin quotas. Note that there can be only
one application cache per application.
The Web SQL Database API provides storage which is private to a given origin.
Similar to the Application Cache, use of the Web SQL Database can be attributed
to an origin. It is also possible to set per-origin quotas.Modifier and Type | Class and Description |
---|---|
static class |
WebStorage.Origin
This class encapsulates information about the amount of storage
currently used by an origin for the JavaScript storage APIs.
|
static interface |
WebStorage.QuotaUpdater
Deprecated.
This class is obsolete and no longer used.
|
Constructor and Description |
---|
WebStorage()
This class should not be instantiated directly, applications must only use
getInstance() to obtain the instance. |
Modifier and Type | Method and Description |
---|---|
void |
deleteAllData()
Clears all storage currently being used by the JavaScript storage APIs.
|
void |
deleteOrigin(String origin)
Clears the storage currently being used by both the Application Cache and
Web SQL Database APIs by the given origin.
|
static WebStorage |
getInstance()
Gets the singleton instance of this class.
|
void |
getOrigins(ValueCallback<Map> callback)
Gets the origins currently using either the Application Cache or Web SQL
Database APIs.
|
void |
getQuotaForOrigin(String origin,
ValueCallback<Long> callback)
Gets the storage quota for the Web SQL Database API for the given origin.
|
void |
getUsageForOrigin(String origin,
ValueCallback<Long> callback)
Gets the amount of storage currently being used by both the Application
Cache and Web SQL Database APIs by the given origin.
|
void |
setQuotaForOrigin(String origin,
long quota)
Deprecated.
Controlling quota per-origin will not be supported in future.
|
public WebStorage()
getInstance()
to obtain the instance.
Note this constructor was erroneously public and published in SDK levels prior to 16, but
applications using it would receive a non-functional instance of this class (there was no
way to call createHandler() and createUIHandler(), so it would not work).public void getOrigins(ValueCallback<Map> callback)
ValueCallback
. The origins are provided as
a map, of type Map<String, WebStorage.Origin>
, from the string
representation of the origin to a WebStorage.Origin
object.public void getUsageForOrigin(String origin, ValueCallback<Long> callback)
ValueCallback
.public void getQuotaForOrigin(String origin, ValueCallback<Long> callback)
ValueCallback
. Note that a quota is not
enforced on a per-origin basis for the Application Cache API.@Deprecated public void setQuotaForOrigin(String origin, long quota)
public void deleteOrigin(String origin)
public void deleteAllData()
public static WebStorage getInstance()
WebStorage
instance