org.simpleframework.xml.util
Class ConcurrentCache<T>

java.lang.Object
  extended by java.util.AbstractMap<K,V>
      extended by java.util.concurrent.ConcurrentHashMap<Object,T>
          extended by org.simpleframework.xml.util.ConcurrentCache<T>
All Implemented Interfaces:
Serializable, ConcurrentMap<Object,T>, Map<Object,T>, Cache<T>

public class ConcurrentCache<T>
extends ConcurrentHashMap<Object,T>
implements Cache<T>

The ConcurrentCache interface is used to represent a cache that will store key value pairs. This implementation is backed by a ConcurrentHashMap for best performance.

Author:
Niall Gallagher
See Also:
Serialized Form

Nested Class Summary
 
Nested classes/interfaces inherited from class java.util.AbstractMap
AbstractMap.SimpleEntry<K,V>, AbstractMap.SimpleImmutableEntry<K,V>
 
Nested classes/interfaces inherited from interface java.util.Map
Map.Entry<K,V>
 
Constructor Summary
ConcurrentCache()
          Constructor for the ConcurrentCache object.
 
Method Summary
 void cache(Object key, T value)
          This method is used to insert a key value mapping in to the cache.
 boolean contains(Object key)
          This is used to determine whether the specified key exists with in the cache.
 T fetch(Object key)
          This method is used to get the value from the cache that is mapped to the specified key.
 T take(Object key)
          This is used to exclusively take the value mapped to the specified key from the cache.
 
Methods inherited from class java.util.concurrent.ConcurrentHashMap
clear, containsKey, containsValue, elements, entrySet, get, isEmpty, keys, keySet, put, putAll, putIfAbsent, remove, remove, replace, replace, size, values
 
Methods inherited from class java.util.AbstractMap
clone, equals, hashCode, toString
 
Methods inherited from class java.lang.Object
finalize, getClass, notify, notifyAll, wait, wait, wait
 
Methods inherited from interface org.simpleframework.xml.util.Cache
isEmpty
 
Methods inherited from interface java.util.Map
equals, hashCode
 

Constructor Detail

ConcurrentCache

public ConcurrentCache()
Constructor for the ConcurrentCache object. This is an implementation of a cache that uses the conventional concurrent hash map from the Java collections API.

Method Detail

cache

public void cache(Object key,
                  T value)
This method is used to insert a key value mapping in to the cache. The value can later be retrieved or removed from the cache if desired. If the value associated with the key is null then nothing is stored within the cache.

Specified by:
cache in interface Cache<T>
Parameters:
key - this is the key to cache the provided value to
value - this is the value that is to be cached

take

public T take(Object key)
This is used to exclusively take the value mapped to the specified key from the cache. Invoking this is effectively removing the value from the cache.

Specified by:
take in interface Cache<T>
Parameters:
key - this is the key to acquire the cache value with
Returns:
this returns the value mapped to the specified key

fetch

public T fetch(Object key)
This method is used to get the value from the cache that is mapped to the specified key. If there is no value mapped to the specified key then this method will return a null.

Specified by:
fetch in interface Cache<T>
Parameters:
key - this is the key to acquire the cache value with
Returns:
this returns the value mapped to the specified key

contains

public boolean contains(Object key)
This is used to determine whether the specified key exists with in the cache. Typically this can be done using the fetch method, which will acquire the object.

Specified by:
contains in interface Cache<T>
Overrides:
contains in class ConcurrentHashMap<Object,T>
Parameters:
key - this is the key to check within this segment
Returns:
true if the specified key is within the cache