1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one 3 * or more contributor license agreements. See the NOTICE file 4 * distributed with this work for additional information 5 * regarding copyright ownership. The ASF licenses this file 6 * to you under the Apache License, Version 2.0 (the 7 * "License"); you may not use this file except in compliance 8 * with the License. You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, 13 * software distributed under the License is distributed on an 14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 15 * KIND, either express or implied. See the License for the 16 * specific language governing permissions and limitations 17 * under the License. 18 * 19 */ 20 package org.apache.directory.server.core.changelog; 21 22 23 24 /** 25 * A ChangeLogStore which allows tagging for tracking server state snapshots. 26 * At most one tag per revision can be created. There is no point to creating 27 * more than one tag on a revision in our case for snapshotting server state. 28 * 29 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> 30 * @version $Rev$, $Date$ 31 */ 32 public interface TaggableChangeLogStore extends ChangeLogStore 33 { 34 /** 35 * Creates a tag for a snapshot of the server in a specific state at a revision. 36 * 37 * @param revision the revision to tag the snapshot 38 * @return the Tag associated with the revision 39 * @throws Exception if there is a problem taking a tag, or if 40 * the revision does not exist 41 */ 42 Tag tag( long revision ) throws Exception; 43 44 /** 45 * Creates a snapshot of the server at the current revision. 46 * 47 * @return the revision at which the tag is created 48 * @throws Exception if there is a problem taking a tag 49 */ 50 Tag tag() throws Exception; 51 52 /** 53 * Creates a snapshot of the server at the current revision with a description 54 * of the snapshot tag. 55 * 56 * @param description a description of the state associate with the tag 57 * @return the revision at which the tag is created 58 * @throws Exception if there is a problem taking a tag 59 */ 60 Tag tag( String description ) throws Exception; 61 62 63 /** 64 * Gets the latest tag if one was at all taken. 65 * 66 * @return the last tag to have been created (youngest), or null if no 67 * tags have been created 68 * @throws Exception on failures to access the tag store 69 */ 70 Tag getLatest() throws Exception; 71 72 73 /** 74 * Removes a Tag created for a given revision. 75 * 76 * @param revision the revision number that was tagged 77 * @return the removed tag, null if there is no Tag present with the given revision 78 * @throws Exception on failures to access the tag store 79 */ 80 Tag removeTag( long revision ) throws Exception; 81 82 /** 83 * Creates a tag with the given description for a snapshot of the server 84 * in a specific state at a revision. 85 * 86 * @param revision the revision number that was tagged 87 * @param descrition a description of the state associate with the tag 88 * @return the Tag associated with the revision 89 * @throws Exception on failures to access the tag store 90 */ 91 Tag tag( long revision, String descrition ) throws Exception; 92 }