gov.lbl.dsd.sea.nio.util
Class ByteArrayPool

java.lang.Object
  gov.lbl.dsd.sea.nio.util.ByteArrayPool

public final class ByteArrayPool

extends Object

Simple fixed-size thread-safe pool for recycling byte arrays. Each thread has its own local pool, and each pool can hold at most a given number of byte arrays, evicting arrays beyond that point, as configured through a system property.

Completely unsynchronized, yet thread-safe implementation.

Simple, but often effective if an application creates medium to large temporary arrays at very high frequency, as is often the case in safe and clean I/O buffer management for network servers.

This is not a general purpose replacement for Javas built-in memory and garbage collection subsystem! Do not abuse this class for small or infrequent arrays - those are handled better (read: near-optimal) by the generational garbage collectors and memory allocators of current VMs.

Version:

$Id: ByteArrayPool.java,v 1.5 2004/12/01 21:00:24 hoschek3 Exp $

Method Summary

static void	put(byte[] bytes) Recycles the given byte array back to the pool.
static byte[]	take(int minSize) Returns a byte array that has at least the given size.
static byte[]	takeExactly(int size) Returns a byte array that has exactly the given size.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

takeExactly

public static byte[] takeExactly(int size)

Returns a byte array that has exactly the given size. If there is no such array in the pool, then creates and returns a new array with the given size.

Parameters:

size - the desired size of the byte array.

Returns:

Byte array of desired size.

take

public static byte[] take(int minSize)

Returns a byte array that has at least the given size. If there is no such array in the pool, then creates and returns a new array with the given minSize.

Parameters:

minSize - the minimum desired size of the byte array.

Returns:

Byte array of desired size.

put

public static void put(byte[] bytes)

Recycles the given byte array back to the pool.

Parameters:

bytes - the array to recycle