/*
 * 
 * Copyright 2004 Sun Microsystems, Inc. All Rights Reserved.
 * 
 * The contents of this file are subject to the Sun Community Source
 * License v3.0/Jini Technology Specific Attachment v 1.0 (the
 * "License"). You may not use this file except in compliance with the
 * License. You may obtain a copy of the License at
 * http://wwws.sun.com/software/jini/licensing/SCSL3_JiniTSA1.html.
 * Software distributed under the License is distributed on an "AS IS"
 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
 * the License for the specific language governing rights and limitations
 * under the License.
 * 
 * The Reference Code is Jini Technology Core Platform code, v2.0. The
 * Developer of the Reference Code is Sun Microsystems, Inc.
 * 
 * Contributor(s): Sun Microsystems, Inc.
 * 
 * The contents of this file comply with the Jini Technology Core
 * Platform Compatibility Kit, v2.0A.
 * 
 * Tester(s): Sun Microsystems, Inc.
 * 
 * Test Platform(s):
 * Java 2 SDK, Standard Edition, Version 1.4.2_03 for Solaris(TM)SPARC/x86
 * Java 2 SDK, Standard Edition, Version 1.4.2_03 for Linux (Intel x86)
 * Java 2 SDK, Standard Edition, Version 1.4.2_03 for Windows (Intel Platform)
 * 
 */
package net.jini.id;

/** 
 * Defines an interface that allows a proxy for a resource to express the
 * identity of that resource.  Resources include items like services,
 * leases, service registrations, and lease renewal sets. Any resource that
 * is represented by proxies that implement this interface has a unique
 * identity. That identity is expressed by assigning the resource a
 * universally unique identifier. This universally unique identifier will
 * be represented using the <code>Uuid</code> class. This <code>Uuid</code>
 * must be:
 *
 * <ul>
 * <li> Sufficient to uniquely identify the resource,
 * <li> associated with the resource for the resource's entire lifetime, 
 * <li> never assigned to another resource who's proxies implement 
 *      <code>ReferentUuid</code>, and
 * <li> returned by the <code>getReferentUuid</code> method of
 *      any proxy of the resource, if that proxy implements
 *      <code>ReferentUuid</code>.
 * </ul>
 * <p> 
 * Given two objects, <code>o1</code> and <code>o2</code>, that implement
 * <code>ReferentUuid</code>:
 * <ul>
 * <li> if <code>o1.equals(o2)</code> is <code>true</code>, 
 *      then <code>o1.getReferentUuid</code> and 
 *      <code>o2.getReferentUuid</code> should return equivalent
 *      <code>Uuid</code>s.
 * <li> if <code>o1.getReferentUuid</code> and
 *      <code>o2.getReferentUuid</code> return equivalent
 *      <code>Uuid</code>s, <code>o1.equals(o2)</code> may, but is 
 *      not required to be <code>true</code>.
 * </ul>
 * @author Sun Microsystems, Inc.
 * @see Uuid 
 * @since 2.0
 */
public interface ReferentUuid {
    /**
     * Return the <code>Uuid</code> that has been assigned to the
     * resource this proxy represents.
     * @return the <code>Uuid</code> associated with the
     *         resource this proxy represents. Will not
     *         return <code>null</code>.
     */
    public Uuid getReferentUuid();
}
