org.lsst.ccs.utilities.image.direct

Class DirectByteBufferCache

java.lang.Object

org.lsst.ccs.utilities.image.direct.DirectByteBufferCache

All Implemented Interfaces:

DirectByteBufferCacheMBean

public class DirectByteBufferCache
extends Object
implements DirectByteBufferCacheMBean

Memory allocated in direct buffers is not counted again the Java heap, and as a result can result in a large off-heap memory usage which the garbage collector can be very slow to recover. This class aims to facilitate re-use of existing direct buffers, rather than waiting for the garbage collector to recover the associated memory. This simple-minded implementation keeps an independent cache for each size buffer, and is only suitable for use with a small number of distinct sized buffers.

Author:

tonyj

Method Summary

Modifier and Type	Method and Description
ByteBuffer	allocateDirect(int capacity)
void	free(ByteBuffer byteBuffer)
int	getBufferCount()
Map<Integer,Integer>	getBufferSizeAndCounts()
int	getByteBufferCacheSize()
long	getInUseCapacity()
int	getInUseCount()
long	getTotalCapacity()
static DirectByteBufferCache	instance()
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Method Detail

instance

public static DirectByteBufferCache instance()

allocateDirect

public ByteBuffer allocateDirect(int capacity)

free

public void free(ByteBuffer byteBuffer)

toString

public String toString()

Overrides:

toString in class Object

getBufferCount

public int getBufferCount()

Specified by:

getBufferCount in interface DirectByteBufferCacheMBean

getTotalCapacity

public long getTotalCapacity()

Specified by:

getTotalCapacity in interface DirectByteBufferCacheMBean

getInUseCount

public int getInUseCount()

Specified by:

getInUseCount in interface DirectByteBufferCacheMBean

getInUseCapacity

public long getInUseCapacity()

Specified by:

getInUseCapacity in interface DirectByteBufferCacheMBean

getByteBufferCacheSize

public int getByteBufferCacheSize()

Specified by:

getByteBufferCacheSize in interface DirectByteBufferCacheMBean

getBufferSizeAndCounts

public Map<Integer,Integer> getBufferSizeAndCounts()

Specified by:

getBufferSizeAndCounts in interface DirectByteBufferCacheMBean