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A bundle project producing JAX-RS RI bundles. The primary artifact is an "all-in-one" OSGi-fied JAX-RS RI bundle (jaxrs-ri.jar). Attached to that are two compressed JAX-RS RI archives. The first archive (jaxrs-ri.zip) consists of binary RI bits and contains the API jar (under "api" directory), RI libraries (under "lib" directory) as well as all external RI dependencies (under "ext" directory). The secondary archive (jaxrs-ri-src.zip) contains buildable JAX-RS RI source bundle and contains the API jar (under "api" directory), RI sources (under "src" directory) as well as all external RI dependencies (under "ext" directory). The second archive also contains "build.xml" ANT script that builds the RI sources. To build the JAX-RS RI simply unzip the archive, cd to the created jaxrs-ri directory and invoke "ant" from the command line.

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/*
 * Copyright (c) 2012, 2019 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0, which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the
 * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
 * version 2 with the GNU Classpath Exception, which is available at
 * https://www.gnu.org/software/classpath/license.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
 */

package org.glassfish.jersey.internal.util;

import java.io.Serializable;
import java.util.UUID;
import java.util.concurrent.atomic.AtomicReference;

/**
 * Lazily initialized, thread-safe, random UUID. Useful for identifying instances
 * for logging & debugging purposes.
 * 
 * The UUID value gets initialized with the first call to {@link #value()} method.
 * Once initialized, the UUID value stays the same.
 *
 * @author Marek Potociar
 */
public class LazyUid implements Serializable {
    private static final long serialVersionUID = 4618609413877136867L;

    private final AtomicReference uid = new AtomicReference();

    /**
     * Return UUID value. The returned value is never {@code null}.
     *
     * @return UUID value.
     */
    public String value() {
        if (uid.get() == null) {
            uid.compareAndSet(null, UUID.randomUUID().toString());
        }

        return uid.get();
    }

    @Override
    public boolean equals(Object that) {
        if (that == null) {
            return false;
        }
        if (getClass() != that.getClass()) {
            return false;
        }
        final LazyUid other = (LazyUid) that;
        return this.value().equals(other.value());
    }

    @Override
    public int hashCode() {
        int hash = 7;
        hash = 73 * hash + this.value().hashCode();
        return hash;
    }

    @Override
    public String toString() {
        return value();
    }
}