Package org.springframework.util
Class ConcurrentReferenceHashMap.Segment
- java.lang.Object
- java.util.concurrent.locks.ReentrantLock
- org.springframework.util.ConcurrentReferenceHashMap.Segment
- All Implemented Interfaces:
Serializable,Lock
- Enclosing class:
- ConcurrentReferenceHashMap<K,V>
protected final class ConcurrentReferenceHashMap.Segment extends ReentrantLock
A single segment used to divide the map to allow better concurrent performance.- See Also:
- Serialized Form
Constructor Summary
Constructors Constructor Description Segment(int initialSize, int resizeThreshold)
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description voidclear()Clear all items from this segment.<T> TdoTask(int hash, Object key, org.springframework.util.ConcurrentReferenceHashMap.Task<T> task)Apply an update operation to this segment.intgetCount()Return the total number of references in this segment.ConcurrentReferenceHashMap.Reference<K,V>getReference(Object key, int hash, ConcurrentReferenceHashMap.Restructure restructure)intgetSize()Return the size of the current references array.protected voidrestructureIfNecessary(boolean allowResize)Restructure the underlying data structure when it becomes necessary.Methods inherited from class java.util.concurrent.locks.ReentrantLock
getHoldCount, getOwner, getQueuedThreads, getQueueLength, getWaitingThreads, getWaitQueueLength, hasQueuedThread, hasQueuedThreads, hasWaiters, isFair, isHeldByCurrentThread, isLocked, lock, lockInterruptibly, newCondition, toString, tryLock, tryLock, unlock
Constructor Detail
Segment
public Segment(int initialSize, int resizeThreshold)
Method Detail
getReference
@Nullable public ConcurrentReferenceHashMap.Reference<K,V> getReference(@Nullable Object key, int hash, ConcurrentReferenceHashMap.Restructure restructure)
doTask
@Nullable public <T> T doTask(int hash, @Nullable Object key, org.springframework.util.ConcurrentReferenceHashMap.Task<T> task)
Apply an update operation to this segment. The segment will be locked during the update.- Parameters:
hash- the hash of the keykey- the keytask- the update operation- Returns:
- the result of the operation
clear
public void clear()
Clear all items from this segment.
restructureIfNecessary
protected final void restructureIfNecessary(boolean allowResize)
Restructure the underlying data structure when it becomes necessary. This method can increase the size of the references table as well as purge any references that have been garbage collected.- Parameters:
allowResize- if resizing is permitted
getSize
public final int getSize()
Return the size of the current references array.
getCount
public final int getCount()
Return the total number of references in this segment.