BytePoolDim1.java

package org.postgresql.core;

/*
 * A simple and efficient class to pool one dimensional byte arrays
 * of different sizes.
 */
public class BytePoolDim1
{
	/*
	 * The maximum size of the array we manage.
	 */
	int maxsize = 256;
	/*
	 * The pools not currently in use
	 */
	ObjectPool notusemap[] = new ObjectPool[maxsize + 1];
	/*
	 * The pools currently in use
	 */
	ObjectPool inusemap[] = new ObjectPool[maxsize + 1];
	/*
	 *
	 */
	byte binit[][] = new byte[maxsize + 1][0];

	/*
	 * Construct a new pool
	 */
	public BytePoolDim1()
	{
		for (int i = 0; i <= maxsize; i++)
		{
			binit[i] = new byte[i];
			inusemap[i] = new SimpleObjectPool();
			notusemap[i] = new SimpleObjectPool();
		}
	}

	/*
	 * Allocate a byte[] of a specified size and put it in the pool. If it's
	 * larger than maxsize then it is not pooled.
	 * @return the byte[] allocated
	 */
	public byte[] allocByte(int size)
	{
		// for now until the bug can be removed
		return new byte[size];
		/*
				  // Don't pool if >maxsize
				if (size > maxsize){
				return new byte[size];
			}

				ObjectPool not_usel = notusemap[size];
				ObjectPool in_usel = inusemap[size];
				byte b[] = null;

				  // Fetch from the unused pool if available otherwise allocate a new
				  // now array
				if (!not_usel.isEmpty()) {
				Object o = not_usel.remove();
				b = (byte[]) o;
			} else
				b = new byte[size];
				in_usel.add(b);

				return b;
		*/
	}

	/*
	 * Release an array
	 * @param b byte[] to release
	 */
	public void release(byte[] b)
	{
		// If it's larger than maxsize then we don't touch it
		if (b.length > maxsize)
			return ;

		ObjectPool not_usel = notusemap[b.length];
		ObjectPool in_usel = inusemap[b.length];

		in_usel.remove(b);
		not_usel.add(b);
	}

	/*
	 * Deallocate all
	 * @deprecated Real bad things happen if this is called!
	 */
	public void deallocate()
	{
		//for(int i = 0; i <= maxsize; i++){
		//	  notusemap[i].addAll(inusemap[i]);
		//	  inusemap[i].clear();
		//}
	}
}