org.modeshape.graph.connector.base.cache
Interface NodeCache<KeyType,NodeType extends Node>

Type Parameters:

KeyType - the key for the cache entries, normally the natural unique identifier for the node

NodeType - the node type that is being cached

All Known Subinterfaces:

PathNodeCache<N>

All Known Implementing Classes:

InMemoryNodeCache, InMemoryNodeCache.MapCache, InMemoryNodeCache.PathCache

@ThreadSafe
public interface NodeCache<KeyType,NodeType extends Node>

The basic contract for a workspace-level cache of paths to the nodes stored at that path.

Implementations must provide a no-argument constructor in order to be instantiated by NodeCachePolicy. After instantiation, the assignPolicy(NodeCachePolicy) method will be called to inject the cache policy into the implementation.

Implementations must be thread-safe.

Method Summary

void	assignPolicy(NodeCachePolicy<KeyType,NodeType> policy) Injects the cache policy into the cache
void	clearStatistics() Clears all statistics for this cache
void	close() Indicates that the cache is no longer in use and should relinquish any resources.
NodeType	get(KeyType path) Retrieves the cached node with the given path, it it exists and is valid
CacheStatistics	getStatistics()
void	put(KeyType key, NodeType node) Attempts to cache the given node.
void	remove(KeyType key) Removes the node with the given key from the cache, if it is in currently in the cache.
void	removeAll() Removes all nodes from the cache.

Method Detail

assignPolicy

void assignPolicy(NodeCachePolicy<KeyType,NodeType> policy)

Injects the cache policy into the cache

Parameters:

policy - the active cache policy for the repository source with which this cache is associated

Throws:

IllegalStateException - if this method is called on a cache that has already been initialized.

clearStatistics

void clearStatistics()

Clears all statistics for this cache

getStatistics

CacheStatistics getStatistics()

Returns:

the statistics since the most recent of the cache initialization or the last call to clearStatistics(); never null

get

NodeType get(KeyType path)

Retrieves the cached node with the given path, it it exists and is valid

Parameters:

path - the path for the node to be retrieved

Returns:

the cached node with the given path; may be null if no node with that path is cached or a node with that path is cached but is deemed invalid for implementation-specific reasons

put

void put(KeyType key,
         NodeType node)

Attempts to cache the given node. Implementations must call NodeCachePolicy.shouldCache(Node) on the the assigned policy to determine if the node should be cached.

Parameters:

key - the key for the node that is to be cached; may not be null

node - the node that is to be cached; may not be null

remove

void remove(KeyType key)

Removes the node with the given key from the cache, if it is in currently in the cache. If no node with the given key is currently in the cache, this method returns silently.

Parameters:

key - the key for the node that is to be removed; may not be null

removeAll

void removeAll()

Removes all nodes from the cache.

close

void close()

Indicates that the cache is no longer in use and should relinquish any resources.