Class CacheInterceptor
- All Implemented Interfaces:
Cloneable
,IdentityMap
Purpose: Define a class through which Cache access can be intercepted.
Description: EclipseLink makes extensive use of caching functionality. This class provides the mechanism for intercepting the cache access. Once intercepted applications can allow the process to continue by calling the method on the class attribute targetIdentityMap as described in the API javadocs or redirect the process entirely. * As with IdentityMaps an entire class inheritance hierarchy will share the same interceptor.
To implement a CacheInterceptor users should subclass this class implementing those methods they wish to intercept.
Configuration: Interceptors may be added to a session by using a Session or Descriptor customizer to set the class name of the interceptor on the target ClassDescriptor through the method setCacheInterceptorClass(Class).
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Field Summary
Modifier and TypeFieldDescriptionprotected AbstractSession
protected IdentityMap
This attribute stores the actual IdentityMap as configured by the user. -
Constructor Summary
ModifierConstructorDescriptionprotected
CacheInterceptor
(IdentityMap targetIdentityMap, AbstractSession interceptedSession) -
Method Summary
Modifier and TypeMethodDescriptionacquireDeferredLock
(Object primaryKey, boolean isCacheCheckComplete) Acquire a deferred lock on the object.acquireLock
(Object primaryKey, boolean forMerge, boolean isCacheCheckComplete) Acquire an active lock on the object.acquireLockNoWait
(Object primaryKey, boolean forMerge) Acquire an active lock on the object, if not already locked.acquireLockWithWait
(Object primaryKey, boolean forMerge, int wait) Acquire an active lock on the object, if not already locked.acquireReadLockOnCacheKey
(Object primaryKey) Acquire a read lock on the object.acquireReadLockOnCacheKeyNoWait
(Object primaryKey) Acquire a read lock on the object, if not already locked.abstract Object
clone()
Clone the map and all of the CacheKeys.Allow for theCacheKey
elements to be iterated.void
collectLocks
(HashMap threadList) Add all locked CacheKeys to the map grouped by thread.boolean
containsKey
(Object primaryKey) Return true if an CacheKey with the primary key is in the map.protected abstract CacheKeyInterceptor
createCacheKeyInterceptor
(CacheKey wrappedCacheKey) elements()
Allow for the cache to be iterated on.Return the object cached in the identity map or null if it could not be found.getAllCacheKeysFromIdentityMapWithEntityPK
(Object[] pkList, ClassDescriptor descriptor, AbstractSession session) ADVANCED: Using a list of Entity PK this method will attempt to bulk load the entire list from the cache.getAllFromIdentityMapWithEntityPK
(Object[] pkList, ClassDescriptor descriptor, AbstractSession session) ADVANCED: Using a list of Entity PK this method will attempt to bulk load the entire list from the cache.getCacheKey
(Object primaryKey, boolean forMerge) Get the cache key (with object) for the primary key.getCacheKeyForLock
(Object primaryKey) Get the cache key (with object) for the primary key.Return the descriptor that this is the map for.Class
<?> Return the class that this is the map for.int
int
getSize()
Return the number of CacheKeys in the IdentityMap.int
Return the number of actual objects of type myClass in the IdentityMap.Return the instance of the IdentityMap that this intercpetor is wrapping.getWrapper
(Object primaryKey) Get the wrapper object from the cache key associated with the given primary key, this is used for EJB2.getWriteLockValue
(Object primaryKey) Get the write lock value from the cache key associated to the primarykey.keys()
Allow for theCacheKey
elements to be iterated.keys
(boolean checkReadLocks) Allow for theCacheKey
elements to be iterated.void
lazyRelationshipLoaded
(Object rootEntity, ValueHolderInterface valueHolder, ForeignReferenceMapping mapping) Notify the cache that a lazy relationship has been triggered in the object and the cache may need to be updatedStore the object in the cache at its primary key.Remove the CacheKey with the primaryKey from the map.Remove the CacheKey from the map.void
setDescriptor
(ClassDescriptor descriptor) Set the descriptor that this is the map for.void
setWrapper
(Object primaryKey, Object wrapper) Update the wrapper object in the CacheKey associated with the given primaryKey, this is used for EJB2.void
setWriteLockValue
(Object primaryKey, Object writeLockValue) Update the write lock value of the CacheKey associated with the given primaryKey.toString()
void
updateMaxSize
(int maxSize) This method will be used to update the max cache size, any objects exceeding the max cache size will be remove from the cache.Methods inherited from class java.lang.Object
equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
Methods inherited from interface org.eclipse.persistence.internal.identitymaps.IdentityMap
release
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Field Details
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targetIdentityMap
This attribute stores the actual IdentityMap as configured by the user. -
interceptedSession
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Constructor Details
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CacheInterceptor
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Method Details
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acquireDeferredLock
Acquire a deferred lock on the object. This is used while reading if the object has relationships without indirection. This first thread will get an active lock. Other threads will get deferred locks, all threads will wait until all other threads are complete before releasing their locks.- Specified by:
acquireDeferredLock
in interfaceIdentityMap
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acquireLock
Acquire an active lock on the object. This is used by reading (when using indirection or no relationships) and by merge.- Specified by:
acquireLock
in interfaceIdentityMap
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acquireLockNoWait
Acquire an active lock on the object, if not already locked. This is used by merge for missing existing objects.- Specified by:
acquireLockNoWait
in interfaceIdentityMap
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acquireLockWithWait
Acquire an active lock on the object, if not already locked. This is used by merge for missing existing objects.- Specified by:
acquireLockWithWait
in interfaceIdentityMap
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acquireReadLockOnCacheKey
Acquire a read lock on the object. This is used by UnitOfWork cloning. This will allow multiple users to read the same object but prevent writes to the object while the read lock is held.- Specified by:
acquireReadLockOnCacheKey
in interfaceIdentityMap
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acquireReadLockOnCacheKeyNoWait
Acquire a read lock on the object, if not already locked. This is used by UnitOfWork cloning. This will allow multiple users to read the same object but prevent writes to the object while the read lock is held.- Specified by:
acquireReadLockOnCacheKeyNoWait
in interfaceIdentityMap
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collectLocks
Add all locked CacheKeys to the map grouped by thread. Used to print all the locks in the identity map.- Specified by:
collectLocks
in interfaceIdentityMap
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clone
Clone the map and all of the CacheKeys. This is used by UnitOfWork commitAndResumeOnFailure to avoid corrupting the cache during a failed commit.- Specified by:
clone
in interfaceIdentityMap
- Overrides:
clone
in classObject
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containsKey
Return true if an CacheKey with the primary key is in the map. User API.- Specified by:
containsKey
in interfaceIdentityMap
- Parameters:
primaryKey
- is the primary key for the object to search for.
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createCacheKeyInterceptor
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elements
Allow for the cache to be iterated on. This method is only used during debugging when validateCache() has been called to print out the contents of the cache.- Specified by:
elements
in interfaceIdentityMap
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get
Return the object cached in the identity map or null if it could not be found. User API.- Specified by:
get
in interfaceIdentityMap
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getAllFromIdentityMapWithEntityPK
public abstract Map<Object,Object> getAllFromIdentityMapWithEntityPK(Object[] pkList, ClassDescriptor descriptor, AbstractSession session) ADVANCED: Using a list of Entity PK this method will attempt to bulk load the entire list from the cache. In certain circumstances this can have large performance improvements over loading each item individually.- Specified by:
getAllFromIdentityMapWithEntityPK
in interfaceIdentityMap
- Parameters:
pkList
- List of Entity PKs to extract from the cachedescriptor
- Descriptor type to be retrieved.- Returns:
- Map of Entity PKs associated to the Entities that were retrieved
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getAllCacheKeysFromIdentityMapWithEntityPK
public abstract Map<Object,CacheKey> getAllCacheKeysFromIdentityMapWithEntityPK(Object[] pkList, ClassDescriptor descriptor, AbstractSession session) ADVANCED: Using a list of Entity PK this method will attempt to bulk load the entire list from the cache. In certain circumstances this can have large performance improvements over loading each item individually.- Specified by:
getAllCacheKeysFromIdentityMapWithEntityPK
in interfaceIdentityMap
- Parameters:
pkList
- List of Entity PKs to extract from the cachedescriptor
- Descriptor type to be retrieved.- Returns:
- Map of Entity PKs associated to the Entities that were retrieved
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getCacheKey
Get the cache key (with object) for the primary key.- Specified by:
getCacheKey
in interfaceIdentityMap
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getCacheKeyForLock
Get the cache key (with object) for the primary key.- Specified by:
getCacheKeyForLock
in interfaceIdentityMap
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getDescriptor
Return the descriptor that this is the map for.- Specified by:
getDescriptor
in interfaceIdentityMap
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getDescriptorClass
Return the class that this is the map for.- Specified by:
getDescriptorClass
in interfaceIdentityMap
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getMaxSize
public int getMaxSize()- Specified by:
getMaxSize
in interfaceIdentityMap
- Returns:
- The maxSize for the IdentityMap (NOTE: some subclasses may use this differently).
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getSize
public int getSize()Return the number of CacheKeys in the IdentityMap. This may contain weak referenced objects that have been garbage collected.- Specified by:
getSize
in interfaceIdentityMap
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getSize
Return the number of actual objects of type myClass in the IdentityMap. Recurse = true will include subclasses of myClass in the count.- Specified by:
getSize
in interfaceIdentityMap
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getTargetIdenttyMap
Return the instance of the IdentityMap that this intercpetor is wrapping. Any call that is to be passed on to the underlying EclipseLink cache should be passed to this IdentityMap. -
getWrapper
Get the wrapper object from the cache key associated with the given primary key, this is used for EJB2.- Specified by:
getWrapper
in interfaceIdentityMap
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getWriteLockValue
Get the write lock value from the cache key associated to the primarykey. User API.- Specified by:
getWriteLockValue
in interfaceIdentityMap
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keys
Allow for theCacheKey
elements to be iterated.CacheKey
Collection
is reused so this iteration may not be thread safe.- Specified by:
keys
in interfaceIdentityMap
- Returns:
Enumeration
ofCacheKey
instances.
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cloneKeys
Allow for theCacheKey
elements to be iterated. Clone ofCacheKey
Collection
is returned so this iteration should be thread safe.- Specified by:
cloneKeys
in interfaceIdentityMap
- Returns:
Enumeration
with clone of theCacheKey
Collection
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keys
Allow for theCacheKey
elements to be iterated.CacheKey
Collection
is reused so this iteration may not be thread safe.- Specified by:
keys
in interfaceIdentityMap
- Parameters:
checkReadLocks
- value oftrue
if read lock on theCacheKey
instances should be checked orfalse
otherwise- Returns:
Enumeration
ofCacheKey
instances.
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lazyRelationshipLoaded
public void lazyRelationshipLoaded(Object rootEntity, ValueHolderInterface valueHolder, ForeignReferenceMapping mapping) Notify the cache that a lazy relationship has been triggered in the object and the cache may need to be updated- Specified by:
lazyRelationshipLoaded
in interfaceIdentityMap
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put
Store the object in the cache at its primary key. This is used by InsertObjectQuery, typically into the UnitOfWork identity map. Merge and reads do not use put, but acquireLock. Also an advanced (very) user API.- Specified by:
put
in interfaceIdentityMap
- Parameters:
primaryKey
- is the primary key for the object.object
- is the domain object to cache.writeLockValue
- is the current write lock value of object, if null the version is ignored.
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remove
Remove the CacheKey with the primaryKey from the map. This is used by DeleteObjectQuery and merge. This is also an advanced (very) user API.- Specified by:
remove
in interfaceIdentityMap
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remove
Remove the CacheKey from the map.- Specified by:
remove
in interfaceIdentityMap
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updateMaxSize
public void updateMaxSize(int maxSize) This method will be used to update the max cache size, any objects exceeding the max cache size will be remove from the cache. Please note that this does not remove the object from the identityMap, except in the case of the CacheIdentityMap.- Specified by:
updateMaxSize
in interfaceIdentityMap
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setDescriptor
Set the descriptor that this is the map for.- Specified by:
setDescriptor
in interfaceIdentityMap
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setWrapper
Update the wrapper object in the CacheKey associated with the given primaryKey, this is used for EJB2.- Specified by:
setWrapper
in interfaceIdentityMap
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setWriteLockValue
Update the write lock value of the CacheKey associated with the given primaryKey. This is used by UpdateObjectQuery, and is also an advanced (very) user API.- Specified by:
setWriteLockValue
in interfaceIdentityMap
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toString
- Specified by:
toString
in interfaceIdentityMap
- Overrides:
toString
in classObject
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