com.google.gwt.storage.client
Class StorageMap

java.lang.Object
  java.util.AbstractMap<java.lang.String,java.lang.String>
      com.google.gwt.storage.client.StorageMap

All Implemented Interfaces:

java.util.Map<java.lang.String,java.lang.String>

public class StorageMap
extends java.util.AbstractMap<java.lang.String,java.lang.String>

Exposes the local/session Storage as a standard Map<String, String>.

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

The following characteristics are associated with this Map:

1. Mutable - All 'write' methods (put(String, String), AbstractMap.putAll(Map), remove(Object), clear(), Entry#setValue(Object)) operate as intended;
2. remove() on Iterators - All remove() operations on available Iterators (from AbstractMap.keySet(), entrySet() and AbstractMap.values()) operate as intended;
3. No null values and keys - The Storage doesn't accept keys or values which are null;
4. String values and keys - All keys and values in this Map are String types.

StorageMap

public StorageMap(Storage storage)

Creates the Map with the specified Storage as data provider.

Parameters:

storage - a local/session Storage instance obtained by either Storage.getLocalStorageIfSupported() or Storage.getSessionStorageIfSupported().

clear

public void clear()

Removes all items from the Storage.

Specified by:

clear in interface java.util.Map<java.lang.String,java.lang.String>

Overrides:

clear in class java.util.AbstractMap<java.lang.String,java.lang.String>

See Also:

Storage.clear()

containsKey

public boolean containsKey(java.lang.Object key)

Returns true if the Storage contains the specified key, false otherwise.

Specified by:

containsKey in interface java.util.Map<java.lang.String,java.lang.String>

Overrides:

containsKey in class java.util.AbstractMap<java.lang.String,java.lang.String>

containsValue

public boolean containsValue(java.lang.Object value)

Returns true if the Storage contains the specified value, false otherwise (or if the specified key is null ).

Specified by:

containsValue in interface java.util.Map<java.lang.String,java.lang.String>

Overrides:

containsValue in class java.util.AbstractMap<java.lang.String,java.lang.String>

entrySet

public java.util.Set<java.util.Map.Entry<java.lang.String,java.lang.String>> entrySet()

Returns a Set containing all entries of the Storage.

Specified by:

entrySet in interface java.util.Map<java.lang.String,java.lang.String>

Specified by:

entrySet in class java.util.AbstractMap<java.lang.String,java.lang.String>

get

public java.lang.String get(java.lang.Object key)

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

Specified by:

get in interface java.util.Map<java.lang.String,java.lang.String>

Overrides:

get in class java.util.AbstractMap<java.lang.String,java.lang.String>

Parameters:

key - the key identifying the value

See Also:

Storage.getItem(String)

put

public java.lang.String put(java.lang.String key,
                            java.lang.String value)

Adds (or overwrites) a new key/value pair in the Storage.

Specified by:

put in interface java.util.Map<java.lang.String,java.lang.String>

Overrides:

put in class java.util.AbstractMap<java.lang.String,java.lang.String>

Parameters:

key - the key identifying the value (not null)

value - the value associated with the key (not null)

See Also:

Storage.setItem(String, String)

remove

public java.lang.String remove(java.lang.Object key)

Removes the key/value pair from the Storage.

Specified by:

remove in interface java.util.Map<java.lang.String,java.lang.String>

Overrides:

remove in class java.util.AbstractMap<java.lang.String,java.lang.String>

Parameters:

key - the key identifying the item to remove

Returns:

the value associated with the key - null if the key was not present in the Storage

See Also:

Storage.removeItem(String)

size

public int size()

Returns the number of items in the Storage.

Specified by:

size in interface java.util.Map<java.lang.String,java.lang.String>

Overrides:

size in class java.util.AbstractMap<java.lang.String,java.lang.String>

Returns:

the number of items

See Also:

Storage.getLength()