org.apache.cayenne.cache

Class MapQueryCache

java.lang.Object

org.apache.cayenne.cache.MapQueryCache

All Implemented Interfaces:

Serializable, QueryCache

public class MapQueryCache
extends Object
implements QueryCache, Serializable

A default implementation of the QueryCache interface that stores data in a non-expiring LRUMap.

Since:

3.0

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected Map<String,Map<String,List<?>>>	cacheGroups
static int	DEFAULT_CACHE_SIZE

Constructor Summary

Constructors

Constructor and Description
MapQueryCache()
MapQueryCache(int maxSize)

Method Summary

Modifier and Type	Method and Description
protected String	cacheName(QueryMetadata metadata)
void	clear() Clears all cache entries.
protected Map<String,List<?>>	createCache(String cacheName)
protected Map<String,List<?>>	createIfAbsent(QueryMetadata metadata)
protected Map<String,List<?>>	createIfAbsent(String cacheName)
List	get(QueryMetadata metadata) Returns a cached query result for the given QueryMetadata or null if the result is not cached or is expired.
List	get(QueryMetadata metadata, QueryCacheEntryFactory factory) Returns a non-null cached value.
protected Map<String,List<?>>	getCache(String name)
void	put(QueryMetadata metadata, List results)
void	remove(String key) Removes a single entry from cache.
void	removeGroup(String groupKey) Removes a group of entries identified by group key.
void	removeGroup(String groupKey, Class<?> keyType, Class<?> valueType) Removes a group of entries identified by group key.
int	size() Returns the number of entries currently in the cache, including expired but not removed entries.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DEFAULT_CACHE_SIZE

public static final int DEFAULT_CACHE_SIZE

See Also:

Constant Field Values

cacheGroups

protected final Map<String,Map<String,List<?>>> cacheGroups

Constructor Detail

MapQueryCache

public MapQueryCache()

MapQueryCache

public MapQueryCache(int maxSize)

Method Detail

get

public List get(QueryMetadata metadata)

Description copied from interface: QueryCache

Returns a cached query result for the given QueryMetadata or null if the result is not cached or is expired.

Specified by:

get in interface QueryCache

get

public List get(QueryMetadata metadata,
                QueryCacheEntryFactory factory)

Returns a non-null cached value. If it is not present in the cache, it is obtained by calling QueryCacheEntryFactory.createObject() without blocking the cache. As a result there is a potential of multiple threads to be updating cache in parallel - this wouldn't lead to corruption of the cache, but can be suboptimal.

Specified by:

get in interface QueryCache

put

public void put(QueryMetadata metadata,
                List results)

Specified by:

put in interface QueryCache

remove

public void remove(String key)

Description copied from interface: QueryCache

Removes a single entry from cache.

Specified by:

remove in interface QueryCache

removeGroup

public void removeGroup(String groupKey)

Description copied from interface: QueryCache

Removes a group of entries identified by group key. Note that depending on implementation this method may either actively remove the entries belonging to the group or just mark them as expired, so that they are refreshed on the next access. In the former case the cache size would shrink, but in the later the cache size will not change after calling this method.

Specified by:

removeGroup in interface QueryCache

removeGroup

public void removeGroup(String groupKey,
                        Class<?> keyType,
                        Class<?> valueType)

Description copied from interface: QueryCache

Removes a group of entries identified by group key. Can be used if cache provider supports strictly typed caches.

Specified by:

removeGroup in interface QueryCache

See Also:

QueryCache.removeGroup(String)

clear

public void clear()

Description copied from interface: QueryCache

Clears all cache entries.

Specified by:

clear in interface QueryCache

size

public int size()

Description copied from interface: QueryCache

Returns the number of entries currently in the cache, including expired but not removed entries.

Specified by:

size in interface QueryCache

createIfAbsent

protected Map<String,List<?>> createIfAbsent(QueryMetadata metadata)

createIfAbsent

protected Map<String,List<?>> createIfAbsent(String cacheName)

createCache

protected Map<String,List<?>> createCache(String cacheName)

getCache

protected Map<String,List<?>> getCache(String name)

cacheName

protected String cacheName(QueryMetadata metadata)