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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 sun.misc.Unsafe;

import java.lang.reflect.Field;
import java.lang.reflect.Modifier;
import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;

final class UnsafeAtomicIntegerFieldUpdater extends AtomicIntegerFieldUpdater {
    private final long offset;
    private final Unsafe unsafe;

    UnsafeAtomicIntegerFieldUpdater(Unsafe unsafe, Class tClass, String fieldName) throws NoSuchFieldException {
        Field field = tClass.getDeclaredField(fieldName);
        if (!Modifier.isVolatile(field.getModifiers())) {
            throw new IllegalArgumentException("Must be volatile");
        }
        this.unsafe = unsafe;
        offset = unsafe.objectFieldOffset(field);
    }

    @Override
    public boolean compareAndSet(T obj, int expect, int update) {
        return unsafe.compareAndSwapInt(obj, offset, expect, update);
    }

    @Override
    public boolean weakCompareAndSet(T obj, int expect, int update) {
        return unsafe.compareAndSwapInt(obj, offset, expect, update);
    }

    @Override
    public void set(T obj, int newValue) {
        unsafe.putIntVolatile(obj, offset, newValue);
    }

    @Override
    public void lazySet(T obj, int newValue) {
        unsafe.putOrderedInt(obj, offset, newValue);
    }

    @Override
    public int get(T obj) {
        return unsafe.getIntVolatile(obj, offset);
    }
}