1 /*
2 * Copyright 2007 the original author or authors.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 package org.springframework.ws.transport.mail.monitor;
18
19 import javax.mail.FetchProfile;
20 import javax.mail.Flags;
21 import javax.mail.Folder;
22 import javax.mail.Message;
23 import javax.mail.MessagingException;
24 import javax.mail.search.AndTerm;
25 import javax.mail.search.FlagTerm;
26 import javax.mail.search.SearchTerm;
27
28 import org.apache.commons.logging.Log;
29 import org.apache.commons.logging.LogFactory;
30
31 /**
32 * Abstract base class for the {@link MonitoringStrategy} interface. Exposes a {@link #setDeleteMessages(boolean)
33 * deleteMessages} property, and includes a basic workflow for message monitoring.
34 *
35 * @author Arjen Poutsma
36 * @since 1.5.0
37 */
38 public abstract class AbstractMonitoringStrategy implements MonitoringStrategy {
39
40 /** Logger available to subclasses. */
41 protected final Log logger = LogFactory.getLog(getClass());
42
43 private boolean deleteMessages = true;
44
45 /**
46 * Sets whether messages should be marked as {@link javax.mail.Flags.Flag#DELETED DELETED} after they have been
47 * read. Default is <code>true</code>.
48 */
49 public void setDeleteMessages(boolean deleteMessages) {
50 this.deleteMessages = deleteMessages;
51 }
52
53 public int getFolderOpenMode() {
54 return deleteMessages ? Folder.READ_WRITE : Folder.READ_ONLY;
55 }
56
57 /**
58 * Monitors the given folder, and returns any new messages when they arrive. This implementation calls {@link
59 * #waitForNewMessages(Folder)}, then searches for new messages using {@link #searchForNewMessages(Folder)}, fetches
60 * the messages using {@link #fetchMessages(Folder, Message[])}, and finally {@link #setDeleteMessages(boolean)
61 * deletes} the messages, if {@link #setDeleteMessages(boolean) deleteMessages} is <code>true</code>.
62 *
63 * @param folder the folder to monitor
64 * @return the new messages
65 * @throws MessagingException in case of JavaMail errors
66 * @throws InterruptedException when a thread is interrupted
67 */
68 public final Message[] monitor(Folder folder) throws MessagingException, InterruptedException {
69 waitForNewMessages(folder);
70 Message[] messages = searchForNewMessages(folder);
71 if (logger.isDebugEnabled()) {
72 logger.debug("Found " + messages.length + " new messages");
73 }
74 if (messages.length > 0) {
75 fetchMessages(folder, messages);
76 }
77 if (deleteMessages) {
78 deleteMessages(folder, messages);
79 }
80 return messages;
81 }
82
83 /**
84 * Template method that blocks until new messages arrive in the given folder. Typical implementations use {@link
85 * Thread#sleep(long)} or the IMAP IDLE command.
86 *
87 * @param folder the folder to monitor
88 * @throws MessagingException in case of JavaMail errors
89 * @throws InterruptedException when a thread is interrupted
90 */
91 protected abstract void waitForNewMessages(Folder folder) throws MessagingException, InterruptedException;
92
93 /**
94 * Retrieves new messages from the given folder. This implementation creates a {@link SearchTerm} that searches for
95 * all messages in the folder that are {@link javax.mail.Flags.Flag#RECENT RECENT}, not {@link
96 * javax.mail.Flags.Flag#ANSWERED ANSWERED}, and not {@link javax.mail.Flags.Flag#DELETED DELETED}. The search term
97 * is used to {@link Folder#search(SearchTerm) search} for new messages.
98 *
99 * @param folder the folder to retrieve new messages from
100 * @return the new messages
101 * @throws MessagingException in case of JavaMail errors
102 */
103 protected Message[] searchForNewMessages(Folder folder) throws MessagingException {
104 if (!folder.isOpen()) {
105 return new Message[0];
106 }
107 Flags supportedFlags = folder.getPermanentFlags();
108 SearchTerm searchTerm = null;
109 if (supportedFlags != null) {
110 if (supportedFlags.contains(Flags.Flag.RECENT)) {
111 searchTerm = new FlagTerm(new Flags(Flags.Flag.RECENT), true);
112 }
113 if (supportedFlags.contains(Flags.Flag.ANSWERED)) {
114 FlagTerm answeredTerm = new FlagTerm(new Flags(Flags.Flag.ANSWERED), false);
115 if (searchTerm == null) {
116 searchTerm = answeredTerm;
117 }
118 else {
119 searchTerm = new AndTerm(searchTerm, answeredTerm);
120 }
121 }
122 if (supportedFlags.contains(Flags.Flag.DELETED)) {
123 FlagTerm deletedTerm = new FlagTerm(new Flags(Flags.Flag.DELETED), false);
124 if (searchTerm == null) {
125 searchTerm = deletedTerm;
126 }
127 else {
128 searchTerm = new AndTerm(searchTerm, deletedTerm);
129 }
130 }
131 }
132 return searchTerm != null ? folder.search(searchTerm) : folder.getMessages();
133 }
134
135 /**
136 * Fetches the specified messages from the specified folder. Default implementation {@link Folder#fetch(Message[],
137 * FetchProfile) fetches} every {@link javax.mail.FetchProfile.Item}.
138 *
139 * @param folder the folder to fetch messages from
140 * @param messages the messages to fetch
141 * @throws MessagingException in case of JavMail errors
142 */
143 protected void fetchMessages(Folder folder, Message[] messages) throws MessagingException {
144 FetchProfile contentsProfile = new FetchProfile();
145 contentsProfile.add(FetchProfile.Item.ENVELOPE);
146 contentsProfile.add(FetchProfile.Item.CONTENT_INFO);
147 contentsProfile.add(FetchProfile.Item.FLAGS);
148 folder.fetch(messages, contentsProfile);
149 }
150
151 /**
152 * Deletes the given messages from the given folder. Only invoked when {@link #setDeleteMessages(boolean)} is
153 * <code>true</code>.
154 *
155 * @param folder the folder to delete messages from
156 * @param messages the messages to delete
157 * @throws MessagingException in case of JavaMail errors
158 */
159 protected void deleteMessages(Folder folder, Message[] messages) throws MessagingException {
160 for (int i = 0; i < messages.length; i++) {
161 messages[i].setFlag(Flags.Flag.DELETED, true);
162 }
163 }
164 }