/*
 * Copyright (c) 2005, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package com.sun.xml.internal.stream.util;

import java.lang.ref.*;

Buffer allocator for buffers of sizes 128 B, 2 KB and 8 KB. Includes methods for allocating and freeing buffers.
Author:Binu John, Santiago PericasGeertsen
/** * Buffer allocator for buffers of sizes 128 B, 2 KB and 8 KB. Includes * methods for allocating and freeing buffers. * * @author Binu John * @author Santiago PericasGeertsen */
public class BufferAllocator { private static final int SMALL_SIZE_LIMIT = 128; private static final int MEDIUM_SIZE_LIMIT = 2048; private static final int LARGE_SIZE_LIMIT = 8192; char[] smallCharBuffer; char[] mediumCharBuffer; char[] largeCharBuffer; byte[] smallByteBuffer; byte[] mediumByteBuffer; byte[] largeByteBuffer; public BufferAllocator() { } public char[] getCharBuffer(int size) { if (size <= SMALL_SIZE_LIMIT) { char[] buffer = smallCharBuffer; smallCharBuffer = null; return buffer; } else if (size <= MEDIUM_SIZE_LIMIT) { char[] buffer = mediumCharBuffer; mediumCharBuffer = null; return buffer; } else if (size <= LARGE_SIZE_LIMIT) { char[] buffer = largeCharBuffer; largeCharBuffer = null; return buffer; } return null; } public void returnCharBuffer(char[] c) { if (c == null) { return; } if (c.length <= SMALL_SIZE_LIMIT) { smallCharBuffer = c; } else if (c.length <= MEDIUM_SIZE_LIMIT) { mediumCharBuffer = c; } else if (c.length <= LARGE_SIZE_LIMIT) { largeCharBuffer = c; } } public byte[] getByteBuffer(int size) { if (size <= SMALL_SIZE_LIMIT) { byte[] buffer = smallByteBuffer; smallByteBuffer = null; return buffer; } else if (size <= MEDIUM_SIZE_LIMIT) { byte[] buffer = mediumByteBuffer; mediumByteBuffer = null; return buffer; } else if (size <= LARGE_SIZE_LIMIT) { byte[] buffer = largeByteBuffer; largeByteBuffer = null; return buffer; } return null; } public void returnByteBuffer(byte[] b) { if (b == null) { return; } if (b.length <= SMALL_SIZE_LIMIT) { smallByteBuffer = b; } else if (b.length <= MEDIUM_SIZE_LIMIT) { mediumByteBuffer = b; } else if (b.length <= LARGE_SIZE_LIMIT) { largeByteBuffer = b; } } }