Mercurial > hg > blitz_condensed
comparison src/com/go/trove/net/DistributedSocketFactory.java @ 0:3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
author | Dan Creswell <dan.creswell@gmail.com> |
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date | Sat, 21 Mar 2009 11:00:06 +0000 |
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-1:000000000000 | 0:3dc0c5604566 |
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1 /* ==================================================================== | |
2 * Trove - Copyright (c) 1997-2000 Walt Disney Internet Group | |
3 * ==================================================================== | |
4 * The Tea Software License, Version 1.1 | |
5 * | |
6 * Copyright (c) 2000 Walt Disney Internet Group. All rights reserved. | |
7 * | |
8 * Redistribution and use in source and binary forms, with or without | |
9 * modification, are permitted provided that the following conditions | |
10 * are met: | |
11 * | |
12 * 1. Redistributions of source code must retain the above copyright | |
13 * notice, this list of conditions and the following disclaimer. | |
14 * | |
15 * 2. Redistributions in binary form must reproduce the above copyright | |
16 * notice, this list of conditions and the following disclaimer in | |
17 * the documentation and/or other materials provided with the | |
18 * distribution. | |
19 * | |
20 * 3. The end-user documentation included with the redistribution, | |
21 * if any, must include the following acknowledgment: | |
22 * "This product includes software developed by the | |
23 * Walt Disney Internet Group (http://opensource.go.com/)." | |
24 * Alternately, this acknowledgment may appear in the software itself, | |
25 * if and wherever such third-party acknowledgments normally appear. | |
26 * | |
27 * 4. The names "Tea", "TeaServlet", "Kettle", "Trove" and "BeanDoc" must | |
28 * not be used to endorse or promote products derived from this | |
29 * software without prior written permission. For written | |
30 * permission, please contact opensource@dig.com. | |
31 * | |
32 * 5. Products derived from this software may not be called "Tea", | |
33 * "TeaServlet", "Kettle" or "Trove", nor may "Tea", "TeaServlet", | |
34 * "Kettle", "Trove" or "BeanDoc" appear in their name, without prior | |
35 * written permission of the Walt Disney Internet Group. | |
36 * | |
37 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED | |
38 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES | |
39 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE | |
40 * DISCLAIMED. IN NO EVENT SHALL THE WALT DISNEY INTERNET GROUP OR ITS | |
41 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, | |
42 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, | |
43 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR | |
44 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY | |
45 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
46 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE | |
47 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
48 * ==================================================================== | |
49 * | |
50 * For more information about Tea, please see http://opensource.go.com/. | |
51 */ | |
52 | |
53 package com.go.trove.net; | |
54 | |
55 import java.io.*; | |
56 import java.net.*; | |
57 import java.util.*; | |
58 import java.lang.ref.*; | |
59 import com.go.trove.util.IdentityMap; | |
60 | |
61 /****************************************************************************** | |
62 * A SocketFactory implementation for distributing load among several | |
63 * SocketFactories. If an exception occurs on a socket, its pool is put into | |
64 * the "dead" list. A special thread will run in the background, trying to | |
65 * resurrect the dead SocketSocket. As soon as its able to create sockets | |
66 * again, its added back into the "live" list. | |
67 * <p> | |
68 * Consider wrapping with a {@link LazySocketFactory} for automatic checking | |
69 * against socket factories that may be dead. | |
70 * | |
71 * @author Brian S O'Neill | |
72 * @version | |
73 * <!--$$Revision: 1.1 $-->, <!--$$JustDate:--> 01/01/22 <!-- $--> | |
74 */ | |
75 public class DistributedSocketFactory implements SocketFactory { | |
76 private final long mTimeout; | |
77 | |
78 private int mFactoryIndex; | |
79 | |
80 // Contains only the live SocketFactories. | |
81 private List mFactories; | |
82 | |
83 // Maps SocketPools to resurrector threads. | |
84 private Map mResurrectors; | |
85 | |
86 // Maps CheckedSockets to the SocketPools that they came from. | |
87 private Map mSocketSources; | |
88 | |
89 private CheckedSocket.ExceptionListener mListener; | |
90 | |
91 /** | |
92 * @param timeout Maximum time to wait (in milliseconds) for new | |
93 * connections to be established before throwing an exception | |
94 */ | |
95 public DistributedSocketFactory(long timeout) { | |
96 mTimeout = timeout; | |
97 mFactories = Collections.synchronizedList(new ArrayList()); | |
98 mResurrectors = Collections.synchronizedMap(new HashMap()); | |
99 mSocketSources = Collections.synchronizedMap(new IdentityMap()); | |
100 | |
101 mListener = new CheckedSocket.ExceptionListener() { | |
102 public void exceptionOccurred(CheckedSocket s, Exception e, int count) { | |
103 if (count == 1) { | |
104 deadFactory((SocketFactory)mSocketSources.get(s)); | |
105 } | |
106 } | |
107 }; | |
108 } | |
109 | |
110 public void addSocketFactory(SocketFactory factory) { | |
111 mFactories.add(factory); | |
112 } | |
113 | |
114 public void removeSocketFactory(SocketFactory factory) { | |
115 mFactories.remove(factory); | |
116 Thread t = (Thread)mResurrectors.remove(factory); | |
117 if (t != null) { | |
118 t.interrupt(); | |
119 } | |
120 } | |
121 | |
122 public InetAddressAndPort getInetAddressAndPort() { | |
123 try { | |
124 return getFactory(selectFactory(null)).getInetAddressAndPort(); | |
125 } | |
126 catch (ConnectException e) { | |
127 return InetAddressAndPort.UNKNOWN; | |
128 } | |
129 } | |
130 | |
131 public InetAddressAndPort getInetAddressAndPort(Object session) { | |
132 try { | |
133 return getFactory(selectFactory(session)) | |
134 .getInetAddressAndPort(session); | |
135 } | |
136 catch (ConnectException e) { | |
137 return InetAddressAndPort.UNKNOWN; | |
138 } | |
139 } | |
140 | |
141 public long getDefaultTimeout() { | |
142 return mTimeout; | |
143 } | |
144 | |
145 public CheckedSocket createSocket() | |
146 throws ConnectException, SocketException | |
147 { | |
148 return createSocket(null, mTimeout); | |
149 } | |
150 | |
151 public CheckedSocket createSocket(Object session) | |
152 throws ConnectException, SocketException | |
153 { | |
154 return createSocket(session, mTimeout); | |
155 } | |
156 | |
157 public CheckedSocket createSocket(long timeout) | |
158 throws ConnectException, SocketException | |
159 { | |
160 return createSocket(null, timeout); | |
161 } | |
162 | |
163 public CheckedSocket createSocket(Object session, long timeout) | |
164 throws ConnectException, SocketException | |
165 { | |
166 long startTime = timeout > 0 ? System.currentTimeMillis() : 0; | |
167 int index = selectFactory(session); | |
168 int count = mFactories.size(); | |
169 | |
170 for (int i=0; i<count; i++) { | |
171 SocketFactory factory = null; | |
172 try { | |
173 factory = getFactory(index++); | |
174 CheckedSocket socket = factory.createSocket(session, timeout); | |
175 socket.addExceptionListener(mListener); | |
176 mSocketSources.put(socket, factory); | |
177 return socket; | |
178 } | |
179 catch (SocketException e) { | |
180 deadFactory(factory); | |
181 | |
182 if (timeout == 0) { | |
183 throw e; | |
184 } | |
185 | |
186 if (timeout > 0) { | |
187 timeout -= (System.currentTimeMillis() - startTime); | |
188 if (timeout < 0) { | |
189 throw e; | |
190 } | |
191 } | |
192 } | |
193 } | |
194 | |
195 throw new ConnectException("Unable to create socket"); | |
196 } | |
197 | |
198 public CheckedSocket getSocket() throws ConnectException, SocketException { | |
199 return getSocket(null, mTimeout); | |
200 } | |
201 | |
202 public CheckedSocket getSocket(Object session) | |
203 throws ConnectException, SocketException | |
204 { | |
205 return getSocket(session, mTimeout); | |
206 } | |
207 | |
208 public CheckedSocket getSocket(long timeout) | |
209 throws ConnectException, SocketException | |
210 { | |
211 return getSocket(null, timeout); | |
212 } | |
213 | |
214 public CheckedSocket getSocket(Object session, long timeout) | |
215 throws ConnectException, SocketException | |
216 { | |
217 long startTime = timeout > 0 ? System.currentTimeMillis() : 0; | |
218 int index = selectFactory(session); | |
219 int count = mFactories.size(); | |
220 | |
221 for (int i=0; i<count; i++) { | |
222 SocketFactory factory = null; | |
223 try { | |
224 factory = getFactory(index++); | |
225 CheckedSocket socket = factory.getSocket(session, timeout); | |
226 socket.addExceptionListener(mListener); | |
227 mSocketSources.put(socket, factory); | |
228 return socket; | |
229 } | |
230 catch (SocketException e) { | |
231 deadFactory(factory); | |
232 | |
233 if (timeout == 0) { | |
234 throw e; | |
235 } | |
236 | |
237 if (timeout > 0) { | |
238 timeout -= (System.currentTimeMillis() - startTime); | |
239 if (timeout < 0) { | |
240 throw e; | |
241 } | |
242 } | |
243 } | |
244 } | |
245 | |
246 throw new ConnectException("Unable to get socket"); | |
247 } | |
248 | |
249 public void recycleSocket(CheckedSocket socket) | |
250 throws SocketException, IllegalArgumentException | |
251 { | |
252 if (socket == null) { | |
253 return; | |
254 } | |
255 | |
256 SocketFactory source = (SocketFactory)mSocketSources.remove(socket); | |
257 | |
258 if (source == null) { | |
259 throw new IllegalArgumentException | |
260 ("Socket did not originate from this pool"); | |
261 } | |
262 | |
263 socket.removeExceptionListener(mListener); | |
264 source.recycleSocket(socket); | |
265 } | |
266 | |
267 public void clear() { | |
268 synchronized (mFactories) { | |
269 for (int i = mFactories.size(); --i >= 0; ) { | |
270 ((SocketFactory)mFactories.get(i)).clear(); | |
271 } | |
272 } | |
273 } | |
274 | |
275 public int getAvailableCount() { | |
276 int count = 0; | |
277 synchronized (mFactories) { | |
278 for (int i = mFactories.size(); --i >= 0; ) { | |
279 count += ((SocketFactory)mFactories.get(i)) | |
280 .getAvailableCount(); | |
281 } | |
282 } | |
283 return count; | |
284 } | |
285 | |
286 /** | |
287 * The provided index must be positive, but it can be out of the factory | |
288 * list bounds. | |
289 */ | |
290 private SocketFactory getFactory(int index) throws ConnectException { | |
291 synchronized (mFactories) { | |
292 int size = mFactories.size(); | |
293 if (size <= 0) { | |
294 throw new ConnectException("No SocketFactories available"); | |
295 } | |
296 return (SocketFactory)mFactories.get(index % size); | |
297 } | |
298 } | |
299 | |
300 /** | |
301 * Returns an index which is positive, but may be out of the factory list | |
302 * bounds. | |
303 */ | |
304 private int selectFactory(Object session) throws ConnectException { | |
305 if (session != null) { | |
306 return session.hashCode() & 0x7fffffff; | |
307 } | |
308 else { | |
309 synchronized (mFactories) { | |
310 return mFactoryIndex++ & 0x7fffffff; | |
311 } | |
312 } | |
313 } | |
314 | |
315 private void deadFactory(SocketFactory factory) { | |
316 if (factory == null) { | |
317 return; | |
318 } | |
319 | |
320 synchronized (mFactories) { | |
321 // Only remove factory if its not the last one left. | |
322 if (mFactories.contains(factory) && mFactories.size() > 1) { | |
323 mFactories.remove(factory); | |
324 | |
325 Resurrector r = new Resurrector(this, factory); | |
326 Thread t = new Thread(null, r, "Resurrector " + | |
327 factory.getInetAddressAndPort()); | |
328 t.setDaemon(true); | |
329 t.start(); | |
330 mResurrectors.put(factory, t); | |
331 } | |
332 } | |
333 } | |
334 | |
335 private static class Resurrector implements Runnable { | |
336 // Weakly references owner so that this thread won't prevent it from | |
337 // being garbage collected. | |
338 private final Reference mOwner; | |
339 private final SocketFactory mFactory; | |
340 | |
341 public Resurrector(DistributedSocketFactory owner, | |
342 SocketFactory factory) { | |
343 mOwner = new WeakReference(owner); | |
344 mFactory = factory; | |
345 } | |
346 | |
347 public void run() { | |
348 DistributedSocketFactory owner = null; | |
349 try { | |
350 while (!Thread.interrupted()) { | |
351 owner = (DistributedSocketFactory)mOwner.get(); | |
352 if (owner == null) { | |
353 break; | |
354 } | |
355 | |
356 try { | |
357 mFactory.recycleSocket(mFactory.createSocket()); | |
358 owner.mFactories.add(mFactory); | |
359 break; | |
360 } | |
361 catch (IOException e) { | |
362 } | |
363 | |
364 owner = null; | |
365 | |
366 // Wait at 5 seconds before trying again. | |
367 try { | |
368 Thread.sleep(5000); | |
369 } | |
370 catch (InterruptedException e) { | |
371 break; | |
372 } | |
373 } | |
374 } | |
375 finally { | |
376 owner = (DistributedSocketFactory)mOwner.get(); | |
377 if (owner != null) { | |
378 owner.mResurrectors.remove(mFactory); | |
379 } | |
380 } | |
381 } | |
382 } | |
383 } |