001/*
002* CDDL HEADER START
003 *
004 * The contents of this file are subject to the terms of the
005 * Common Development and Distribution License, Version 1.0 only
006 * (the "License").  You may not use this file except in compliance
007 * with the License.
008 *
009 * You can obtain a copy of the license at legal-notices/CDDLv1_0.txt
010 * or http://forgerock.org/license/CDDLv1.0.html.
011 * See the License for the specific language governing permissions
012 * and limitations under the License.
013 *
014 * When distributing Covered Code, include this CDDL HEADER in each
015 * file and include the License file at legal-notices/CDDLv1_0.txt.
016 * If applicable, add the following below this CDDL HEADER, with the
017 * fields enclosed by brackets "[]" replaced with your own identifying
018 * information:
019 *      Portions Copyright [yyyy] [name of copyright owner]
020 *
021 * CDDL HEADER END
022 *
023 *
024 *       Copyright 2010 Sun Microsystems, Inc.
025 *       Portions copyright 2013 ForgeRock AS.
026 */
027
028package org.forgerock.opendj.server.core;
029
030import java.util.Set;
031
032/**
033 * Interface declares common functionality for objects, which can store
034 * {@link Attachment}s.
035 */
036public interface AttachmentHolder {
037    /**
038     * Retrieves the attachment with the specified name.
039     *
040     * @param name
041     *            The name for the attachment to retrieve. It will be treated in
042     *            a case-sensitive manner.
043     * @return The requested attachment object, or {@code null} if it does not
044     *         exist.
045     */
046    Object getAttachment(String name);
047
048    /**
049     * Retrieves the set of attachment names defined for this holder, as a
050     * mapping between the attachment name and the associated object.
051     *
052     * @return The set of attachments defined for this operation.
053     */
054    Set<String> getAttachmentNames();
055
056    /**
057     * Removes the attachment with the specified name.
058     *
059     * @param name
060     *            The name for the attachment to remove. It will be treated in a
061     *            case-sensitive manner.
062     * @return The attachment that was removed, or {@code null} if it does not
063     *         exist.
064     */
065    Object removeAttachment(String name);
066
067    /**
068     * Sets the value of the specified attachment. If an attachment already
069     * exists with the same name, it will be replaced. Otherwise, a new
070     * attachment will be added.
071     *
072     * @param name
073     *            The name to use for the attachment.
074     * @param value
075     *            The value to use for the attachment.
076     * @return The former value held by the attachment with the given name, or
077     *         {@code null} if there was previously no such attachment.
078     */
079    Object setAttachment(String name, Object value);
080}