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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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/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2014 Red Hat, Inc., and individual contributors
 * as indicated by the @author tags.
 *
 * Licensed 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 org.wildfly.common.ref;

import java.lang.ref.ReferenceQueue;

/**
 * A reapable weak reference with an attachment.  If a {@link Reaper} is given, then it will be used to asynchronously
 * clean up the referent.
 *
 * @param  the reference value type
 * @param  the attachment type
 *
 * @see java.lang.ref.WeakReference
 *
 * @author David M. Lloyd
 */
public class WeakReference extends java.lang.ref.WeakReference implements Reference, Reapable {
    private final A attachment;
    private final Reaper reaper;

    /**
     * Construct a new instance.
     *
     * @param referent the referent
     */
    public WeakReference(final T referent) {
        this(referent, null, (Reaper) null);
    }

    /**
     * Construct a new instance.
     *
     * @param referent the referent
     * @param attachment the attachment
     */
    public WeakReference(final T referent, final A attachment) {
        this(referent, attachment, (Reaper) null);
    }

    /**
     * Construct a new instance with an explicit reference queue.
     *
     * @param referent the referent
     * @param attachment the attachment
     * @param q the reference queue to use
     */
    public WeakReference(final T referent, final A attachment, final ReferenceQueue q) {
        super(referent, q);
        this.attachment = attachment;
        reaper = null;
    }

    /**
     * Construct a new instance with a reaper.
     *
     * @param referent the referent
     * @param attachment the attachment
     * @param reaper the reaper to use
     */
    public WeakReference(final T referent, final A attachment, final Reaper reaper) {
        super(referent, References.ReaperThread.REAPER_QUEUE);
        this.attachment = attachment;
        this.reaper = reaper;
    }

    public A getAttachment() {
        return attachment;
    }

    public Type getType() {
        return Type.WEAK;
    }

    public Reaper getReaper() {
        return reaper;
    }

    public String toString() {
        return "weak reference to " + String.valueOf(get());
    }
}