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 2013-2015 ForgeRock AS
025 */
026package org.opends.server.replication.server.changelog.api;
027
028import org.opends.server.replication.common.CSN;
029import org.opends.server.types.DN;
030
031/**
032 * This class stores an index of all the changes seen by this server in the form
033 * of {@link ChangeNumberIndexRecord}s. The records are sorted by a global
034 * ordering as defined in the CSN class. The index links a
035 * <code>changeNumber</code> to the corresponding CSN. The CSN then links to a
036 * corresponding change in one of the ReplicaDBs.
037 *
038 * @see <a href=
039 * "https://wikis.forgerock.org/confluence/display/OPENDJ/OpenDJ+Domain+Names"
040 * >OpenDJ Domain Names</a> for more information about the changelog.
041 * @see <a href= "http://tools.ietf.org/html/draft-good-ldap-changelog-04"
042 * >OpenDJ Domain Names</a> for more information about the changeNumber.
043 */
044public interface ChangeNumberIndexDB
045{
046
047  /**
048   * Returns the last generated change number.
049   *
050   * @return the last generated change number
051   */
052  long getLastGeneratedChangeNumber();
053
054  /**
055   * Get the oldest record stored in this DB.
056   *
057   * @return Returns the oldest {@link ChangeNumberIndexRecord} in this DB, null
058   *         when the DB is empty or closed
059   * @throws ChangelogException
060   *           if a database problem occurs.
061   */
062  ChangeNumberIndexRecord getOldestRecord() throws ChangelogException;
063
064  /**
065   * Get the newest record stored in this DB.
066   *
067   * @return Returns the newest {@link ChangeNumberIndexRecord} in this DB, null
068   *         when the DB is empty or closed
069   * @throws ChangelogException
070   *           if a database problem occurs.
071   */
072  ChangeNumberIndexRecord getNewestRecord() throws ChangelogException;
073
074  /**
075   * Add an update to the list of messages that must be saved to this DB managed
076   * by this DB and return the changeNumber associated to this record.
077   * <p>
078   * Note: this method disregards the changeNumber in the provided record.
079   *
080   * @param record
081   *          The {@link ChangeNumberIndexRecord} to add to this DB.
082   * @return the change number associated to this record on adding to this DB
083   * @throws ChangelogException
084   *           if a database problem occurs.
085   */
086  long addRecord(ChangeNumberIndexRecord record) throws ChangelogException;
087
088  /**
089   * Generate a new {@link DBCursor} that allows to browse the db managed by
090   * this object and starting at the position defined by a given changeNumber.
091   *
092   * @param startChangeNumber
093   *          The position where the iterator must start.
094   * @return a new DBCursor that allows to browse this DB managed by
095   *         this object and starting at the position defined by a given
096   *         changeNumber.
097   * @throws ChangelogException
098   *           if a database problem occurs.
099   */
100  DBCursor<ChangeNumberIndexRecord> getCursorFrom(long startChangeNumber)
101      throws ChangelogException;
102
103  /**
104   * Resets ChangeNumber index to the given number and CSN.
105   * @param newFirstCN
106   *          the new change number to appear as first change in the external changelog
107   * @param baseDN
108   *          the new record for the first change
109   * @param newFirstCSN
110   *          the CSN of the new first change
111   * @throws ChangelogException
112   *          if an error occurs during reset
113   */
114  void resetChangeNumberTo(long newFirstCN, DN baseDN, CSN newFirstCSN) throws ChangelogException;
115}