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This artifact provides a single jar that contains all classes required to use remote Jakarta Enterprise Beans and Jakarta Messaging, including all dependencies. It is intended for use by those not using maven, maven users should just import the Jakarta Enterprise Beans and Jakarta Messaging BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
* Copyright 2014 The Netty Project
*
* The Netty Project licenses this file to you under the Apache License,
* version 2.0 (the "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at:
*
*   http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*/
package io.netty.util.internal;

import io.netty.util.internal.logging.InternalLogger;
import io.netty.util.internal.logging.InternalLoggerFactory;
import sun.misc.Cleaner;

import java.lang.reflect.Field;
import java.nio.ByteBuffer;


/**
 * Allows to free direct {@link ByteBuffer} by using {@link Cleaner}. This is encapsulated in an extra class to be able
 * to use {@link PlatformDependent0} on Android without problems.
 *
 * For more details see #2604.
 */
final class Cleaner0 {
    private static final long CLEANER_FIELD_OFFSET;
    private static final InternalLogger logger = InternalLoggerFactory.getInstance(Cleaner0.class);

    static {
        ByteBuffer direct = ByteBuffer.allocateDirect(1);
        Field cleanerField;
        long fieldOffset = -1;
        if (PlatformDependent0.hasUnsafe()) {
            try {
                cleanerField = direct.getClass().getDeclaredField("cleaner");
                cleanerField.setAccessible(true);
                Cleaner cleaner = (Cleaner) cleanerField.get(direct);
                cleaner.clean();
                fieldOffset = PlatformDependent0.objectFieldOffset(cleanerField);
            } catch (Throwable t) {
                // We don't have ByteBuffer.cleaner().
                fieldOffset = -1;
            }
        }
        logger.debug("java.nio.ByteBuffer.cleaner(): {}", fieldOffset != -1? "available" : "unavailable");
        CLEANER_FIELD_OFFSET = fieldOffset;

        // free buffer if possible
        freeDirectBuffer(direct);
    }

    static void freeDirectBuffer(ByteBuffer buffer) {
        if (CLEANER_FIELD_OFFSET == -1 || !buffer.isDirect()) {
            return;
        }
        try {
            Cleaner cleaner = (Cleaner) PlatformDependent0.getObject(buffer, CLEANER_FIELD_OFFSET);
            if (cleaner != null) {
                cleaner.clean();
            }
        } catch (Throwable t) {
            // Nothing we can do here.
        }
    }

    private Cleaner0() { }
}