1 /* 2 * $Id: UserDatabase.java 471754 2006-11-06 14:55:09Z husted $ 3 * 4 * Licensed to the Apache Software Foundation (ASF) under one 5 * or more contributor license agreements. See the NOTICE file 6 * distributed with this work for additional information 7 * regarding copyright ownership. The ASF licenses this file 8 * to you under the Apache License, Version 2.0 (the 9 * "License"); you may not use this file except in compliance 10 * with the License. You may obtain a copy of the License at 11 * 12 * http://www.apache.org/licenses/LICENSE-2.0 13 * 14 * Unless required by applicable law or agreed to in writing, 15 * software distributed under the License is distributed on an 16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 17 * KIND, either express or implied. See the License for the 18 * specific language governing permissions and limitations 19 * under the License. 20 */ 21 package org.apache.struts.apps.mailreader.dao; 22 23 24 /** 25 * <p>A <strong>Data Access Object</strong> (DAO) interface describing 26 * the available operations for retrieving and storing {@link User}s 27 * (and their associated {@link Subscription}s) in some persistence layer 28 * whose characteristics are not specified here. One or more implementations 29 * will be created to perform the actual I/O that is required.</p> 30 * 31 * @version $Rev: 471754 $ $Date: 2006-11-06 08:55:09 -0600 (Mon, 06 Nov 2006) $ 32 * @since Struts 1.1 33 */ 34 public interface UserDatabase { 35 36 37 // --------------------------------------------------------- Public Methods 38 39 40 /** 41 * <p>Create and return a new {@link User} defined in this user database. 42 * </p> 43 * 44 * @param username Username of the new user 45 * 46 * @exception IllegalArgumentException if the specified username 47 * is not unique 48 */ 49 public User createUser(String username); 50 51 52 /** 53 * <p>Finalize access to the underlying persistence layer.</p> 54 * 55 * @exception Exception if a database access error occurs 56 */ 57 public void close() throws Exception; 58 59 60 /** 61 * <p>Return the existing {@link User} with the specified username, 62 * if any; otherwise return <code>null</code>.</p> 63 * 64 * @param username Username of the user to retrieve 65 * @throws ExpiredPasswordException if user password has expired 66 * and must be changed 67 */ 68 public User findUser(String username) throws ExpiredPasswordException; 69 70 71 /** 72 * <p>Return the set of {@link User}s defined in this user database.</p> 73 */ 74 public User[] findUsers(); 75 76 77 /** 78 * <p>Return true if open() has been called.</p> 79 * 80 * @exception Exception if a database access error occurs 81 */ 82 public boolean isOpen(); 83 84 85 /** 86 * <p>Initiate access to the underlying persistence layer.</p> 87 * 88 * @exception Exception if a database access error occurs 89 */ 90 public void open() throws Exception; 91 92 93 /** 94 * Remove the specified {@link User} from this database. 95 * 96 * @param user User to be removed 97 * 98 * @exception IllegalArgumentException if the specified user is not 99 * associated with this database 100 */ 101 public void removeUser(User user); 102 103 104 /** 105 * <p>Save any pending changes to the underlying persistence layer.</p> 106 * 107 * @exception Exception if a database access error occurs 108 */ 109 public void save() throws Exception; 110 111 112 }