net.sf.ehcache.pool
Interface PoolAccessor<T extends PoolParticipant>

Type Parameters:

T - Type representing this "other" side of this accessor (i.e. a store), so the evictor can interact with it

All Known Implementing Classes:

AbstractPoolAccessor

public interface PoolAccessor<T extends PoolParticipant>

PoolAccessors are used by stores to tell the pools about their resource consumption

Author:

Ludovic Orban, Alex Snaps

Method Summary

long	add(Object key, Object value, Object container, boolean force) Add an element to the pool.
boolean	canAddWithoutEvicting(Object key, Object value, Object container) Check if there is enough room in the pool to add an element without provoking any eviction
void	clear() Free resources used by this accessor.
long	delete(long size) Delete a fixed number of bytes from the pool.
T	getParticipant() Return the store that uses this accessor
long	getPoolOccupancy() Returns the occupied size for this pool.
long	getPoolSize() Returns the size of this pool.
long	getSize() Return how many bytes this accessor consumes from the pool.
boolean	hasAbortedSizeOf() Check if the store may contain elements which the SizeOf engine could not fully size.
long	replace(long currentSize, Object key, Object value, Object container, boolean force) Delete a fixed number of bytes from the pool with the given objects.
void	setMaxSize(long newValue) Sets the max size for this pool
void	unlink() unlink this PoolAccessor from its pool.

Method Detail

add

long add(Object key,
         Object value,
         Object container,
         boolean force)

Add an element to the pool.

Parameters:

key - the key of the element

value - the value of the element

container - the element-container object

force - true if the pool should accept adding the element, even if it's out of resources

Returns:

how many bytes have been added to the pool or -1 if add failed.

canAddWithoutEvicting

boolean canAddWithoutEvicting(Object key,
                              Object value,
                              Object container)

Check if there is enough room in the pool to add an element without provoking any eviction

Parameters:

key - the key of the element

value - the value of the element

container - the element-container object

Returns:

true if there is enough room left

delete

long delete(long size)
            throws IllegalArgumentException

Delete a fixed number of bytes from the pool.

Parameters:

size - number of bytes

Returns:

how many bytes have been freed from the pool.

Throws:

IllegalArgumentException - when sizeOf is negative

replace

long replace(long currentSize,
             Object key,
             Object value,
             Object container,
             boolean force)

Delete a fixed number of bytes from the pool with the given objects.

Parameters:

currentSize - the size of the object(s) being replaced

key - the key of the element

value - the value of the element

container - the element-container object

force - true if the pool should accept replacing the element, even if it's out of resources

Returns:

the change in size of the pool, or Long.MIN_VALUE if replace failed.

getSize

long getSize()

Return how many bytes this accessor consumes from the pool.

Returns:

how many bytes this accessor consumes from the pool.

unlink

void unlink()

unlink this PoolAccessor from its pool.

clear

void clear()

Free resources used by this accessor.

getParticipant

T getParticipant()

Return the store that uses this accessor

Returns:

store using this accessor

setMaxSize

void setMaxSize(long newValue)

Sets the max size for this pool

Parameters:

newValue - the value in bytes

getPoolOccupancy

long getPoolOccupancy()

Returns the occupied size for this pool.

Returns:

occupied pool size

getPoolSize

long getPoolSize()

Returns the size of this pool.

Returns:

pool size

hasAbortedSizeOf

boolean hasAbortedSizeOf()

Check if the store may contain elements which the SizeOf engine could not fully size.

Returns:

true if the store may contain partially sized objects