Class PoolUtils.SynchronizedKeyedObjectPool<K,V>
- Type Parameters:
K
- object pool key typeV
- object pool value type
- All Implemented Interfaces:
Closeable
,AutoCloseable
,KeyedObjectPool<K,
V>
- Enclosing class:
PoolUtils
Note: This should not be used on pool implementations that already
provide proper synchronization such as the pools provided in the Commons
Pool library. Wrapping a pool that waits
for poolable
objects to be returned before allowing another one to be borrowed with
another layer of synchronization will cause liveliness issues or a
deadlock.
-
Field Summary
FieldsModifier and TypeFieldDescriptionprivate final KeyedObjectPool
<K, V> Underlying object poolprivate final ReentrantReadWriteLock
Object whose monitor is used to synchronize methods on the wrapped pool. -
Constructor Summary
ConstructorsConstructorDescriptionSynchronizedKeyedObjectPool
(KeyedObjectPool<K, V> keyedPool) Creates a new SynchronizedKeyedObjectPool wrapping the given pool -
Method Summary
Modifier and TypeMethodDescriptionvoid
Create an object using thefactory
or other implementation dependent mechanism, passivate it, and then place it in the idle object pool.borrowObject
(K key) Obtains an instance from this pool for the specifiedkey
.void
clear()
Clears the pool, removing all pooled instances (optional operation).void
Clears the specified pool, removing all pooled instances corresponding to the givenkey
(optional operation).void
close()
Close this pool, and free any resources associated with it.int
Returns the total number of instances currently borrowed from this pool but not yet returned.int
getNumActive
(K key) Returns the number of instances currently borrowed from but not yet returned to the pool corresponding to the givenkey
.int
Returns the total number of instances currently idle in this pool.int
getNumIdle
(K key) Returns the number of instances corresponding to the givenkey
currently idle in this pool.void
invalidateObject
(K key, V obj) Invalidates an object from the pool.void
returnObject
(K key, V obj) Return an instance to the pool.toString()
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
Methods inherited from interface org.datanucleus.store.rdbms.datasource.dbcp2.pool2.KeyedObjectPool
addObjects, addObjects
-
Field Details
-
readWriteLock
Object whose monitor is used to synchronize methods on the wrapped pool. -
keyedPool
Underlying object pool
-
-
Constructor Details
-
SynchronizedKeyedObjectPool
SynchronizedKeyedObjectPool(KeyedObjectPool<K, V> keyedPool) throws IllegalArgumentExceptionCreates a new SynchronizedKeyedObjectPool wrapping the given pool- Parameters:
keyedPool
- KeyedObjectPool to wrap- Throws:
IllegalArgumentException
- if keyedPool is null
-
-
Method Details
-
borrowObject
Obtains an instance from this pool for the specifiedkey
.Instances returned from this method will have been either newly created with
makeObject
or will be a previously idle object and have been activated withactivateObject
and then (optionally) validated withvalidateObject
.By contract, clients must return the borrowed object using
returnObject
,invalidateObject
, or a related method as defined in an implementation or sub-interface, using akey
that isequivalent
to the one used to borrow the instance in the first place.The behaviour of this method when the pool has been exhausted is not strictly specified (although it may be specified by implementations).
- Specified by:
borrowObject
in interfaceKeyedObjectPool<K,
V> - Parameters:
key
- the key used to obtain the object- Returns:
- an instance from this pool.
- Throws:
Exception
- whenmakeObject
throws an exceptionNoSuchElementException
- when the pool is exhausted and cannot or will not return another instanceIllegalStateException
- afterclose
has been called on this pool
-
returnObject
Return an instance to the pool. By contract,obj
must have been obtained usingborrowObject
or a related method as defined in an implementation or sub-interface using akey
that is equivalent to the one used to borrow the instance in the first place.- Specified by:
returnObject
in interfaceKeyedObjectPool<K,
V> - Parameters:
key
- the key used to obtain the objectobj
- aborrowed
instance to be returned.
-
invalidateObject
Invalidates an object from the pool.By contract,
obj
must have been obtained usingborrowObject
or a related method as defined in an implementation or sub-interface using akey
that is equivalent to the one used to borrow theObject
in the first place.This method should be used when an object that has been borrowed is determined (due to an exception or other problem) to be invalid.
- Specified by:
invalidateObject
in interfaceKeyedObjectPool<K,
V> - Parameters:
key
- the key used to obtain the objectobj
- aborrowed
instance to be returned.
-
addObject
Create an object using thefactory
or other implementation dependent mechanism, passivate it, and then place it in the idle object pool.addObject
is useful for "pre-loading" a pool with idle objects (Optional operation).- Specified by:
addObject
in interfaceKeyedObjectPool<K,
V> - Parameters:
key
- the key a new instance should be added to- Throws:
Exception
- whenKeyedPooledObjectFactory.makeObject(K)
fails.IllegalStateException
- afterKeyedObjectPool.close()
has been called on this pool.UnsupportedOperationException
- when this pool cannot add new idle objects.
-
getNumIdle
Returns the number of instances corresponding to the givenkey
currently idle in this pool. Returns a negative value if this information is not available.- Specified by:
getNumIdle
in interfaceKeyedObjectPool<K,
V> - Parameters:
key
- the key to query- Returns:
- the number of instances corresponding to the given
key
currently idle in this pool.
-
getNumActive
Returns the number of instances currently borrowed from but not yet returned to the pool corresponding to the givenkey
. Returns a negative value if this information is not available.- Specified by:
getNumActive
in interfaceKeyedObjectPool<K,
V> - Parameters:
key
- the key to query- Returns:
- the number of instances currently borrowed from but not yet
returned to the pool corresponding to the given
key
.
-
getNumIdle
public int getNumIdle()Returns the total number of instances currently idle in this pool. Returns a negative value if this information is not available.- Specified by:
getNumIdle
in interfaceKeyedObjectPool<K,
V> - Returns:
- the total number of instances currently idle in this pool.
-
getNumActive
public int getNumActive()Returns the total number of instances currently borrowed from this pool but not yet returned. Returns a negative value if this information is not available.- Specified by:
getNumActive
in interfaceKeyedObjectPool<K,
V> - Returns:
- the total number of instances currently borrowed from this pool but not yet returned.
-
clear
Clears the pool, removing all pooled instances (optional operation).- Specified by:
clear
in interfaceKeyedObjectPool<K,
V> - Throws:
Exception
- if the pool cannot be clearedUnsupportedOperationException
- when this implementation doesn't support the operation
-
clear
Clears the specified pool, removing all pooled instances corresponding to the givenkey
(optional operation).- Specified by:
clear
in interfaceKeyedObjectPool<K,
V> - Parameters:
key
- the key to clear- Throws:
Exception
- if the key cannot be clearedUnsupportedOperationException
- when this implementation doesn't support the operation
-
close
public void close()Close this pool, and free any resources associated with it.Calling
addObject
orborrowObject
after invoking this method on a pool will cause them to throw anIllegalStateException
.Implementations should silently fail if not all resources can be freed.
- Specified by:
close
in interfaceAutoCloseable
- Specified by:
close
in interfaceCloseable
- Specified by:
close
in interfaceKeyedObjectPool<K,
V>
-
toString
-