org.apache.cayenne.cache

Interface QueryCache

All Known Implementing Classes:

EhCacheQueryCache, MapQueryCache, NestedQueryCache, OSQueryCache

public interface QueryCache

Defines API of a cache that stores query results.

Since:

3.0

Method Summary

Modifier and Type	Method and Description
void	clear() Deprecated. since 4.0. Please use implementation specific methods to perform cache management tasks.
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 cached query result for the given QueryMetadata.
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() Deprecated. since 4.0. Please use implementation specific methods to perform cache management tasks.

Method Detail

get

List get(QueryMetadata metadata)

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

get

List get(QueryMetadata metadata,
         QueryCacheEntryFactory factory)

Returns a cached query result for the given QueryMetadata. If the result is not cached or is expired, cache will use provided factory to rebuild the value and store it in the cache. A corollary is that this method never returns null.

Compared to get(QueryMetadata), this method allows the cache to do appropriate synchronization when refreshing the entry, preventing multiple threads from running the same query when a missing entry is requested by multiple threads simultaneously.

put

void put(QueryMetadata metadata,
         List results)

remove

void remove(String key)

Removes a single entry from cache.

removeGroup

void removeGroup(String groupKey)

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.

removeGroup

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

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

Since:

4.0

See Also:

removeGroup(String)

clear

@Deprecated
void clear()

Deprecated. since 4.0. Please use implementation specific methods to perform cache management tasks.

Clears all cache entries.

size

@Deprecated
int size()

Deprecated. since 4.0. Please use implementation specific methods to perform cache management tasks.

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