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 * 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).
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package com.sun.xml.internal.stream.util;

import java.lang.ref.*;

This is a Singleton class that allows you to allocate buffer that
are stored in ThreadLocal. This class stores 3 types of char
buffers - small (< 128 bytes), medium (<2K) and large (> 2K) as
well as three byte buffers - small, medium and large.
The local storage is activated on the return of the buffer.
The buffer returns null if it is already allocated.
Author:
Binu John, Santiago PericasGeertsen/**
 * This is a Singleton class that allows you to allocate buffer that
 * are stored in ThreadLocal. This class stores 3 types of char
 * buffers - small (< 128 bytes), medium (<2K) and large (> 2K) as
 * well as three byte buffers - small, medium and large.
 * The local storage is activated on the return of the buffer.
 * The buffer returns null if it is already allocated.
 *
 * @author Binu John
 * @author Santiago PericasGeertsen
 */
public class ThreadLocalBufferAllocator {
    private static final ThreadLocal<SoftReference<BufferAllocator>> TL = new ThreadLocal<>();

    public static BufferAllocator getBufferAllocator() {
        BufferAllocator ba = null;
        SoftReference<BufferAllocator> sr = TL.get();
        if (sr != null) {
            ba = sr.get();
        }
        if (ba == null) {
            ba = new BufferAllocator();
            sr = new SoftReference<>(ba);
            TL.set(sr);
        }
        return ba;
    }
}