001 package com.croftsoft.apps.wyrm.server;
002
003 import java.rmi.*;
004 import java.util.*;
005 import javax.naming.*;
006 import javax.rmi.*;
007
008 import javax.ejb.*;
009
010 import javax.xml.bind.JAXBException;
011
012 import com.croftsoft.core.lang.NullArgumentException;
013 import com.croftsoft.core.math.MathLib;
014
015 import com.croftsoft.apps.wyrm.WyrmConstants;
016 import com.croftsoft.apps.wyrm.entity.PcLocal;
017 import com.croftsoft.apps.wyrm.entity.PcLocalHome;
018 import com.croftsoft.apps.wyrm.entity.UserLocal;
019 import com.croftsoft.apps.wyrm.entity.UserLocalHome;
020 import com.croftsoft.apps.wyrm.xjc.*;
021
022 /*********************************************************************
023 * Wyrm server stateless session EJB.
024 *
025 * @version
026 * 2002-11-04
027 * @since
028 * 2002-10-17
029 * @author
030 * <a href="http://alumni.caltech.edu/~croft">David Wallace Croft</a>
031 *********************************************************************/
032
033 public class WyrmServerBean
034 implements SessionBean, WyrmConstants
035 //////////////////////////////////////////////////////////////////////
036 //////////////////////////////////////////////////////////////////////
037 {
038
039 private static final String JNDI_PC_LOCAL_HOME
040 = "java:comp/env/ejb/PcLocalHome";
041
042 private static final String JNDI_USER_LOCAL_HOME
043 = "java:comp/env/ejb/UserLocalHome";
044
045 private static final String JNDI_INIT_HEALTH
046 = "java:comp/env/initial_health";
047
048 //
049
050 private static final String STATE_DUNGEON = "dungeon";
051
052 private static final String STATE_HEALER = "healer";
053
054 private static final String STATE_TOWN = "town";
055
056 //
057
058 private static final double INIT_USER_CREDITS = 0.0;
059
060 //
061
062 private static final String INIT_PC_NAME = "Unnamed Hero";
063
064 private static final String INIT_PC_STATE = STATE_TOWN;
065
066 private static final long INIT_PC_HEALTH = 10;
067
068 private static final long INIT_PC_WEALTH = 100;
069
070 private static final long INIT_PC_LEVEL = 0;
071
072 private static final long INIT_PC_EXPERIENCE = 0;
073
074 //
075
076 private static final int HEALING_COST = 10;
077
078 //
079
080 private static final Random random = new Random ( );
081
082 //////////////////////////////////////////////////////////////////////
083 //////////////////////////////////////////////////////////////////////
084
085 public Object serve ( Object requestObject )
086 //////////////////////////////////////////////////////////////////////
087 {
088 try
089 {
090 NullArgumentException.check ( requestObject );
091
092 if ( !( requestObject instanceof Request ) )
093 {
094 String type = requestObject.getClass ( ).getName ( );
095
096 return createResponse (
097 type,
098 false,
099 "unknown request type: " + type,
100 null );
101 }
102
103 Request request = ( Request ) requestObject;
104
105 String requestType = request.getType ( );
106
107 if ( requestType == null )
108 {
109 return createResponse (
110 null,
111 false,
112 "null request type",
113 null );
114 }
115
116 requestType = requestType.trim ( );
117
118 String username = request.getUsername ( );
119
120 String password = request.getPassword ( );
121
122 if ( requestType.equals ( TYPE_CREATE_USER ) )
123 {
124 return serveRequestCreateUser ( username, password );
125 }
126
127 if ( username == null )
128 {
129 return createResponse (
130 TYPE_LOGIN,
131 false,
132 "Welcome to the Wyrm!",
133 null );
134 }
135
136 if ( password == null )
137 {
138 return createResponse (
139 TYPE_LOGIN,
140 false,
141 "Null password.",
142 username );
143 }
144
145 UserLocal userLocal = getUserLocal ( username, password );
146
147 if ( userLocal == null )
148 {
149 return createResponse (
150 TYPE_LOGIN,
151 false,
152 "Unknown username or incorrect password.",
153 username );
154 }
155
156 try
157 {
158 if ( requestType.equals ( TYPE_ACCOUNT ) )
159 {
160 return serveRequestAccount ( userLocal );
161 }
162
163 if ( requestType.equals ( TYPE_DESTROY_USER ) )
164 {
165 return serveRequestDestroyUser ( userLocal );
166 }
167
168 if ( requestType.equals ( TYPE_DUNGEON ) )
169 {
170 return serveRequestDungeon ( userLocal );
171 }
172
173 if ( requestType.equals ( TYPE_FIGHT ) )
174 {
175 return serveRequestFight ( userLocal );
176 }
177
178 if ( requestType.equals ( TYPE_FLEE ) )
179 {
180 return serveRequestFlee ( userLocal );
181 }
182
183 if ( requestType.equals ( TYPE_HEAL ) )
184 {
185 return serveRequestHeal ( userLocal );
186 }
187
188 if ( requestType.equals ( TYPE_HEALER ) )
189 {
190 return serveRequestHealer ( userLocal );
191 }
192
193 if ( requestType.equals ( TYPE_LOGIN ) )
194 {
195 return serveRequestLogin ( userLocal );
196 }
197
198 if ( requestType.equals ( TYPE_LOGOUT ) )
199 {
200 return serveRequestLogout ( username );
201 }
202
203 if ( requestType.equals ( TYPE_STATE ) )
204 {
205 return serveRequestState ( userLocal );
206 }
207
208 if ( requestType.equals ( TYPE_TOWN ) )
209 {
210 return serveRequestTown ( userLocal );
211 }
212 }
213 catch ( IllegalStateException ex )
214 {
215 ResponseState responseState = serveRequestState ( userLocal );
216
217 responseState.setMessage (
218 "Your request is not allowed from here." );
219
220 return responseState;
221 }
222
223 return createResponse (
224 requestType,
225 false,
226 "unknown request type: " + requestType,
227 username );
228 }
229 catch ( Exception ex )
230 {
231 // Throwing EJBException will cause the transaction to be
232 // rolled back automatically.
233 // See p433, Monson-Haefel, "Enterprise Java Beans", 3rd Ed., 2001
234
235 throw new EJBException ( ex );
236 }
237 }
238
239 //////////////////////////////////////////////////////////////////////
240 //////////////////////////////////////////////////////////////////////
241
242 private Object serveRequestAccount ( UserLocal userLocal )
243 throws Exception
244 //////////////////////////////////////////////////////////////////////
245 {
246 ResponseAccount responseAccount
247 = ObjectFactory.createResponseAccount ( );
248
249 responseAccount.setUsername ( userLocal.getUsername ( ) );
250
251 responseAccount.setFirstName ( userLocal.getFirstName ( ) );
252
253 responseAccount.setMiddleName ( userLocal.getMiddleName ( ) );
254
255 responseAccount.setLastName ( userLocal.getLastName ( ) );
256
257 responseAccount.setCredits ( userLocal.getCredits ( ) );
258
259 return responseAccount;
260 }
261
262 private Object serveRequestCreateUser (
263 String username,
264 String password )
265 throws Exception
266 //////////////////////////////////////////////////////////////////////
267 {
268 if ( username == null )
269 {
270 return createResponse (
271 TYPE_CREATE_USER,
272 false,
273 null,
274 null );
275 }
276
277 boolean granted
278 = ( password != null )
279 && !"".equals ( username.trim ( ) )
280 && !"".equals ( password.trim ( ) )
281 && username.equals ( username.toLowerCase ( ) )
282 && username.equals ( username.trim ( ) );
283
284 // TODO: Need to also check that username just letters, numbers,
285 // and underscore with no white space as well.
286
287 if ( !granted )
288 {
289 return createResponse (
290 TYPE_CREATE_USER,
291 false,
292 "Bad username or password.",
293 username );
294 }
295
296 Context context = new InitialContext ( );
297
298 Object obj = context.lookup ( JNDI_USER_LOCAL_HOME );
299
300 UserLocalHome userLocalHome = ( UserLocalHome )
301 PortableRemoteObject.narrow ( obj, UserLocalHome.class );
302
303 UserLocal userLocal = null;
304
305 try
306 {
307 userLocal = userLocalHome.findByUsername ( username );
308
309 return createResponse (
310 TYPE_CREATE_USER,
311 false,
312 "Username already in use.",
313 username );
314 }
315 catch ( ObjectNotFoundException ex )
316 {
317 }
318
319 userLocal = userLocalHome.create ( username );
320
321 userLocal.setPassword ( password );
322
323 userLocal.setCredits ( INIT_USER_CREDITS );
324
325 createPcLocal ( userLocal );
326
327 return serveRequestState ( userLocal );
328 }
329
330 private Object serveRequestDestroyUser ( UserLocal userLocal )
331 throws Exception
332 //////////////////////////////////////////////////////////////////////
333 {
334 PcLocal pcLocal = userLocal.getPcLocal ( );
335
336 // This prevents a database persistent memory leak.
337
338 if ( pcLocal != null )
339 {
340 pcLocal.remove ( );
341 }
342
343 String username = userLocal.getUsername ( );
344
345 userLocal.remove ( );
346
347 return createResponse (
348 TYPE_DESTROY_USER,
349 true,
350 "User " + username + " destroyed.",
351 username );
352 }
353
354 private Object serveRequestDungeon ( UserLocal userLocal )
355 throws Exception
356 //////////////////////////////////////////////////////////////////////
357 {
358 PcLocal pcLocal = getPcLocal ( userLocal );
359
360 checkState ( pcLocal, STATE_TOWN );
361
362 pcLocal.setState ( STATE_DUNGEON );
363
364 ResponseState responseState = serveRequestState ( userLocal );
365
366 responseState.setMessage ( "You have entered the dungeon." );
367
368 return responseState;
369 }
370
371 private Object serveRequestFight ( UserLocal userLocal )
372 throws Exception
373 //////////////////////////////////////////////////////////////////////
374 {
375 PcLocal pcLocal = getPcLocal ( userLocal );
376
377 checkState ( pcLocal, STATE_DUNGEON );
378
379 boolean victory = random.nextBoolean ( );
380
381 String message = null;
382
383 if ( victory )
384 {
385 message = "You conquer and find treasure.";
386
387 pcLocal.setWealth ( pcLocal.getWealth ( ) + 1 );
388
389 long experience = pcLocal.getExperience ( ) + 1;
390
391 pcLocal.setExperience ( experience );
392
393 long level = pcLocal.getLevel ( );
394
395 if ( MathLib.log ( experience, 10 ) >= level + 1 )
396 {
397 pcLocal.setLevel ( ++level );
398 }
399 }
400 else
401 {
402 message = "You have been wounded.";
403
404 pcLocal.setHealth ( pcLocal.getHealth ( ) - 1 );
405 }
406
407 ResponseState responseState = serveRequestState ( userLocal );
408
409 responseState.setMessage ( message );
410
411 return responseState;
412 }
413
414 private Object serveRequestFlee ( UserLocal userLocal )
415 throws Exception
416 //////////////////////////////////////////////////////////////////////
417 {
418 PcLocal pcLocal = getPcLocal ( userLocal );
419
420 checkState ( pcLocal, STATE_DUNGEON );
421
422 pcLocal.setState ( STATE_TOWN );
423
424 pcLocal.setHealth ( pcLocal.getHealth ( ) - 1 );
425
426 ResponseState responseState = serveRequestState ( userLocal );
427
428 responseState.setMessage ( "You are wounded as you turn to flee." );
429
430 return responseState;
431 }
432
433 private Object serveRequestHeal ( UserLocal userLocal )
434 throws Exception
435 //////////////////////////////////////////////////////////////////////
436 {
437 PcLocal pcLocal = getPcLocal ( userLocal );
438
439 checkState ( pcLocal, STATE_HEALER );
440
441 pcLocal.setWealth ( pcLocal.getWealth ( ) - HEALING_COST );
442
443 pcLocal.setHealth ( INIT_PC_HEALTH );
444
445 pcLocal.setState ( STATE_TOWN );
446
447 ResponseState responseState = serveRequestState ( userLocal );
448
449 responseState.setMessage (
450 "You return to the town square after being healed." );
451
452 return responseState;
453 }
454
455 private Object serveRequestHealer ( UserLocal userLocal )
456 throws Exception
457 //////////////////////////////////////////////////////////////////////
458 {
459 PcLocal pcLocal = getPcLocal ( userLocal );
460
461 checkState ( pcLocal, STATE_TOWN );
462
463 pcLocal.setState ( STATE_HEALER );
464
465 ResponseState responseState = serveRequestState ( userLocal );
466
467 responseState.setMessage ( "You enter the Healer's hut." );
468
469 return responseState;
470 }
471
472 private Object serveRequestLogin ( UserLocal userLocal )
473 throws Exception
474 //////////////////////////////////////////////////////////////////////
475 {
476 ResponseState responseState = serveRequestState ( userLocal );
477
478 responseState.setMessage ( "Welcome to the Wyrm!" );
479
480 return responseState;
481 }
482
483 private Object serveRequestLogout ( String username )
484 throws Exception
485 //////////////////////////////////////////////////////////////////////
486 {
487 return createResponse (
488 TYPE_LOGOUT,
489 true,
490 "Goodbye.",
491 username );
492 }
493
494 private Object serveRequestTown ( UserLocal userLocal )
495 throws Exception
496 //////////////////////////////////////////////////////////////////////
497 {
498 PcLocal pcLocal = getPcLocal ( userLocal );
499
500 checkState ( pcLocal, STATE_HEALER );
501
502 pcLocal.setState ( STATE_TOWN );
503
504 ResponseState responseState = serveRequestState ( userLocal );
505
506 responseState.setMessage ( "You enter the town square." );
507
508 return responseState;
509 }
510
511 //////////////////////////////////////////////////////////////////////
512 //////////////////////////////////////////////////////////////////////
513
514 private UserLocal getUserLocal (
515 String username,
516 String password )
517 throws Exception
518 //////////////////////////////////////////////////////////////////////
519 {
520 // Can I move some of this code to ejbCreate() so that it is only
521 // executed once?
522
523 InitialContext initialContext = new InitialContext ( );
524
525 Object obj = initialContext.lookup ( JNDI_USER_LOCAL_HOME );
526
527 UserLocalHome userLocalHome = ( UserLocalHome )
528 PortableRemoteObject.narrow ( obj, UserLocalHome.class );
529
530 UserLocal userLocal = null;
531
532 try
533 {
534 userLocal = userLocalHome.findByUsername ( username );
535 }
536 catch ( ObjectNotFoundException ex )
537 {
538 // Can I use userLocalHome.userExists(username) instead?
539
540 return null;
541 }
542
543 if ( !password.equals ( userLocal.getPassword ( ) ) )
544 {
545 return null;
546 }
547
548 return userLocal;
549 }
550
551 private ResponseState serveRequestState ( UserLocal userLocal )
552 throws Exception
553 //////////////////////////////////////////////////////////////////////
554 {
555 ResponseState responseState
556 = ObjectFactory.createResponseState ( );
557
558 responseState.setUsername ( userLocal.getUsername ( ) );
559
560 responseState.setCredits ( userLocal.getCredits ( ) );
561
562 PcLocal pcLocal = getPcLocal ( userLocal );
563
564 responseState.setState ( pcLocal.getState ( ) );
565
566 responseState.setPcName ( pcLocal.getName ( ) );
567
568 responseState.setHealth ( pcLocal.getHealth ( ) );
569
570 responseState.setWealth ( pcLocal.getWealth ( ) );
571
572 responseState.setLevel ( pcLocal.getLevel ( ) );
573
574 responseState.setExperience ( pcLocal.getExperience ( ) );
575
576 responseState.setMessage ( "" );
577
578 return responseState;
579 }
580
581 private PcLocal getPcLocal ( UserLocal userLocal )
582 throws Exception
583 //////////////////////////////////////////////////////////////////////
584 {
585 PcLocal pcLocal = userLocal.getPcLocal ( );
586
587 if ( pcLocal == null )
588 {
589 pcLocal = createPcLocal ( userLocal );
590 }
591
592 return pcLocal;
593 }
594
595 private PcLocal createPcLocal ( UserLocal userLocal )
596 throws Exception
597 //////////////////////////////////////////////////////////////////////
598 {
599 InitialContext initialContext = new InitialContext ( );
600
601 Object obj = initialContext.lookup ( JNDI_PC_LOCAL_HOME );
602
603 PcLocalHome pcLocalHome = ( PcLocalHome )
604 PortableRemoteObject.narrow ( obj, PcLocalHome.class );
605
606 PcLocal pcLocal = pcLocalHome.create ( );
607
608 pcLocal.setName ( INIT_PC_NAME );
609
610 pcLocal.setState ( INIT_PC_STATE );
611
612 pcLocal.setHealth ( INIT_PC_HEALTH );
613
614 pcLocal.setWealth ( INIT_PC_WEALTH );
615
616 pcLocal.setLevel ( INIT_PC_LEVEL );
617
618 pcLocal.setExperience ( INIT_PC_EXPERIENCE );
619
620 userLocal.setPcLocal ( pcLocal );
621
622 Long envInitHealth
623 = ( Long ) initialContext.lookup ( JNDI_INIT_HEALTH );
624
625 if ( envInitHealth != null )
626 {
627 pcLocal.setHealth ( envInitHealth.longValue ( ) );
628 }
629
630 return pcLocal;
631 }
632
633 private void checkState (
634 PcLocal pcLocal,
635 String desiredState )
636 throws Exception
637 //////////////////////////////////////////////////////////////////////
638 {
639 String state = pcLocal.getState ( );
640
641 if ( state == null )
642 {
643 state = INIT_PC_STATE;
644 }
645
646 if ( !state.equals ( desiredState ) )
647 {
648 throw new IllegalStateException ( );
649 }
650 }
651
652 private Response createResponse (
653 String type,
654 boolean granted,
655 String message,
656 String username )
657 throws Exception
658 //////////////////////////////////////////////////////////////////////
659 {
660 Response response = ObjectFactory.createResponse ( );
661
662 response.setType ( type );
663
664 response.setGranted ( granted );
665
666 response.setMessage ( message != null ? message : "" );
667
668 response.setUsername ( username != null ? username : "" );
669
670 return response;
671 }
672
673 //////////////////////////////////////////////////////////////////////
674 //////////////////////////////////////////////////////////////////////
675
676 public void ejbActivate ( ) { }
677
678 public void ejbCreate ( ) { }
679
680 public void ejbPassivate ( ) { }
681
682 public void ejbRemove ( ) { }
683
684 public void setSessionContext ( SessionContext sessionContext ) { }
685
686 //////////////////////////////////////////////////////////////////////
687 //////////////////////////////////////////////////////////////////////
688 }