StorageMap (Google Web Toolkit Javadoc)

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(), Map.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. JavaScriptException instead of NullPointerException - Some Map (or other Collection) methods mandate the use of a NullPointerException if some argument is null (e.g. remove(Object) remove(null)). this Map emits JavaScriptExceptions instead;
5. String values and keys - All keys and values in this Map are String types.

Nested Class Summary
- Nested classes/interfaces inherited from class java.util.AbstractMap
  java.util.AbstractMap.SimpleEntry<K,V>, java.util.AbstractMap.SimpleImmutableEntry<K,V>
- Nested classes/interfaces inherited from interface java.util.Map
  java.util.Map.Entry<K,V>

Constructor Summary

Constructors
Constructor and Description

StorageMap(Storage storage)
Creates the Map with the specified Storage as data provider.

Constructors
Constructor and Description
`StorageMap(Storage storage)` Creates the Map with the specified Storage as data provider.

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`clear()` Removes all items from the Storage.
`boolean`	`containsKey(java.lang.Object key)` Returns `true` if the Storage contains the specified key, `false` otherwise.
`boolean`	`containsValue(java.lang.Object value)` Returns `true` if the Storage contains the specified value, `false` otherwise (or if the specified key is `null` ).
`java.util.Set<java.util.Map.Entry<java.lang.String,java.lang.String>>`	`entrySet()` Returns a Set containing all entries of the Storage.
`java.lang.String`	`get(java.lang.Object key)` Returns the value associated with the specified key in the Storage.
`java.lang.String`	`put(java.lang.String key, java.lang.String value)` Adds (or overwrites) a new key/value pair in the Storage.
`java.lang.String`	`remove(java.lang.Object key)` Removes the key/value pair from the Storage.
`int`	`size()` Returns the number of items in the Storage.

Methods inherited from class java.util.AbstractMap
clone, equals, hashCode, isEmpty, keySet, putAll, toString, values

Methods inherited from class java.lang.Object
finalize, getClass, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - 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().
- Method Detail
  - 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()

Class StorageMap

Nested Class Summary

Nested classes/interfaces inherited from class java.util.AbstractMap

Nested classes/interfaces inherited from interface java.util.Map

Constructor Summary

Method Summary

Methods inherited from class java.util.AbstractMap

Methods inherited from class java.lang.Object

Constructor Detail

StorageMap

Method Detail

clear

containsKey

containsValue

entrySet

get

put

remove

size