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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS 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:
*
*   https://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 java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.nio.ByteBuffer;
import java.security.AccessController;
import java.security.PrivilegedAction;


/**
 * Allows to free direct {@link ByteBuffer} by using 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 CleanerJava6 implements Cleaner {
    private static final long CLEANER_FIELD_OFFSET;
    private static final Method CLEAN_METHOD;
    private static final Field CLEANER_FIELD;

    private static final InternalLogger logger = InternalLoggerFactory.getInstance(CleanerJava6.class);

    static {
        long fieldOffset;
        Method clean;
        Field cleanerField;
        Throwable error = null;
        final ByteBuffer direct = ByteBuffer.allocateDirect(1);
        try {
            Object mayBeCleanerField = AccessController.doPrivileged(new PrivilegedAction() {
                @Override
                public Object run() {
                    try {
                        Field cleanerField =  direct.getClass().getDeclaredField("cleaner");
                        if (!PlatformDependent.hasUnsafe()) {
                            // We need to make it accessible if we do not use Unsafe as we will access it via
                            // reflection.
                            cleanerField.setAccessible(true);
                        }
                        return cleanerField;
                    } catch (Throwable cause) {
                        return cause;
                    }
                }
            });
            if (mayBeCleanerField instanceof Throwable) {
                throw (Throwable) mayBeCleanerField;
            }

            cleanerField = (Field) mayBeCleanerField;

            final Object cleaner;

            // If we have sun.misc.Unsafe we will use it as its faster then using reflection,
            // otherwise let us try reflection as last resort.
            if (PlatformDependent.hasUnsafe()) {
                fieldOffset = PlatformDependent0.objectFieldOffset(cleanerField);
                cleaner = PlatformDependent0.getObject(direct, fieldOffset);
            } else {
                fieldOffset = -1;
                cleaner = cleanerField.get(direct);
            }
            clean = cleaner.getClass().getDeclaredMethod("clean");
            clean.invoke(cleaner);
        } catch (Throwable t) {
            // We don't have ByteBuffer.cleaner().
            fieldOffset = -1;
            clean = null;
            error = t;
            cleanerField = null;
        }

        if (error == null) {
            logger.debug("java.nio.ByteBuffer.cleaner(): available");
        } else {
            logger.debug("java.nio.ByteBuffer.cleaner(): unavailable", error);
        }
        CLEANER_FIELD = cleanerField;
        CLEANER_FIELD_OFFSET = fieldOffset;
        CLEAN_METHOD = clean;
    }

    static boolean isSupported() {
        return CLEANER_FIELD_OFFSET != -1 || CLEANER_FIELD != null;
    }

    @Override
    public void freeDirectBuffer(ByteBuffer buffer) {
        if (!buffer.isDirect()) {
            return;
        }
        if (System.getSecurityManager() == null) {
            try {
                freeDirectBuffer0(buffer);
            } catch (Throwable cause) {
                PlatformDependent0.throwException(cause);
            }
        } else {
            freeDirectBufferPrivileged(buffer);
        }
    }

    private static void freeDirectBufferPrivileged(final ByteBuffer buffer) {
        Throwable cause = AccessController.doPrivileged(new PrivilegedAction() {
            @Override
            public Throwable run() {
                try {
                    freeDirectBuffer0(buffer);
                    return null;
                } catch (Throwable cause) {
                    return cause;
                }
            }
        });
        if (cause != null) {
            PlatformDependent0.throwException(cause);
        }
    }

    private static void freeDirectBuffer0(ByteBuffer buffer) throws Exception {
        final Object cleaner;
        // If CLEANER_FIELD_OFFSET == -1 we need to use reflection to access the cleaner, otherwise we can use
        // sun.misc.Unsafe.
        if (CLEANER_FIELD_OFFSET == -1) {
            cleaner = CLEANER_FIELD.get(buffer);
        } else {
            cleaner = PlatformDependent0.getObject(buffer, CLEANER_FIELD_OFFSET);
        }
        if (cleaner != null) {
            CLEAN_METHOD.invoke(cleaner);
        }
    }
}
    

    

    

            

    

            



    
    






    
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