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.mina.proxy.event;
21
22 import java.util.LinkedList;
23 import java.util.Queue;
24
25 import org.apache.mina.proxy.handlers.socks.SocksProxyRequest;
26 import org.apache.mina.proxy.session.ProxyIoSession;
27 import org.slf4j.Logger;
28 import org.slf4j.LoggerFactory;
29
30 /**
31 * IoSessionEventQueue.java - Queue that contains filtered session events
32 * while handshake isn't done.
33 *
34 * @author The Apache MINA Project (dev@mina.apache.org)
35 * @since MINA 2.0.0-M3
36 */
37 public class IoSessionEventQueue {
38 private final static Logger logger = LoggerFactory
39 .getLogger(IoSessionEventQueue.class);
40
41 /**
42 * The proxy session object.
43 */
44 private ProxyIoSession proxyIoSession;
45
46 /**
47 * Queue of session events which occurred before the proxy handshake had completed.
48 */
49 private Queue<IoSessionEvent> sessionEventsQueue = new LinkedList<IoSessionEvent>();
50
51 public IoSessionEventQueue(ProxyIoSession proxyIoSession) {
52 this.proxyIoSession = proxyIoSession;
53 }
54
55 /**
56 * Discard all events from the queue.
57 */
58 private void discardSessionQueueEvents() {
59 synchronized (sessionEventsQueue) {
60 // Free queue
61 sessionEventsQueue.clear();
62 logger.debug("Event queue CLEARED");
63 }
64 }
65
66 /**
67 * Event is enqueued only if necessary :
68 * - socks proxies do not need the reconnection feature so events are always
69 * forwarded for these.
70 * - http proxies events will be enqueued while handshake has not been completed
71 * or until connection was closed.
72 * If connection was prematurely closed previous events are discarded and only the
73 * session closed is delivered.
74 *
75 * @param evt the event to enqueue
76 */
77 public void enqueueEventIfNecessary(final IoSessionEvent evt) {
78 logger.debug("??? >> Enqueue {}", evt);
79
80 if (proxyIoSession.getRequest() instanceof SocksProxyRequest) {
81 // No reconnection used
82 evt.deliverEvent();
83 return;
84 }
85
86 if (proxyIoSession.getHandler().isHandshakeComplete()) {
87 evt.deliverEvent();
88 } else {
89 if (evt.getType() == IoSessionEventType.CLOSED) {
90 if (proxyIoSession.isAuthenticationFailed()) {
91 proxyIoSession.getConnector().cancelConnectFuture();
92 discardSessionQueueEvents();
93 evt.deliverEvent();
94 } else {
95 discardSessionQueueEvents();
96 }
97 } else if (evt.getType() == IoSessionEventType.OPENED) {
98 // Enqueue event cause it will not reach IoHandler but deliver it to enable
99 // session creation.
100 enqueueSessionEvent(evt);
101 evt.deliverEvent();
102 } else {
103 enqueueSessionEvent(evt);
104 }
105 }
106 }
107
108 /**
109 * Send any session event which were queued while waiting for handshaking to complete.
110 *
111 * Please note this is an internal method. DO NOT USE it in your code.
112 */
113 public void flushPendingSessionEvents() throws Exception {
114 synchronized (sessionEventsQueue) {
115 IoSessionEvent evt;
116
117 while ((evt = sessionEventsQueue.poll()) != null) {
118 logger.debug(" Flushing buffered event: {}", evt);
119 evt.deliverEvent();
120 }
121 }
122 }
123
124 /**
125 * Enqueue an event to be delivered once handshaking is complete.
126 *
127 * @param evt the session event to enqueue
128 */
129 private void enqueueSessionEvent(final IoSessionEvent evt) {
130 synchronized (sessionEventsQueue) {
131 logger.debug("Enqueuing event: {}", evt);
132 sessionEventsQueue.offer(evt);
133 }
134 }
135 }