J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 1999-2007 Sun Microsystems, Inc. All Rights Reserved. |
| 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 4 | * |
| 5 | * This code is free software; you can redistribute it and/or modify it |
| 6 | * under the terms of the GNU General Public License version 2 only, as |
| 7 | * published by the Free Software Foundation. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun in the LICENSE file that accompanied this code. |
| 10 | * |
| 11 | * This code is distributed in the hope that it will be useful, but WITHOUT |
| 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| 14 | * version 2 for more details (a copy is included in the LICENSE file that |
| 15 | * accompanied this code). |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License version |
| 18 | * 2 along with this work; if not, write to the Free Software Foundation, |
| 19 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| 20 | * |
| 21 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | |
| 27 | package com.sun.jmx.snmp.daemon; |
| 28 | |
| 29 | |
| 30 | |
| 31 | // java import |
| 32 | // |
| 33 | import java.io.ObjectInputStream; |
| 34 | import java.io.IOException; |
| 35 | import java.net.InetAddress; |
| 36 | import java.util.Enumeration; |
| 37 | import java.util.logging.Level; |
| 38 | import java.util.Vector; |
| 39 | import java.util.NoSuchElementException; |
| 40 | |
| 41 | // jmx import |
| 42 | // |
| 43 | import javax.management.MBeanServer; |
| 44 | import javax.management.MBeanRegistration; |
| 45 | import javax.management.ObjectName; |
| 46 | import javax.management.NotificationListener; |
| 47 | import javax.management.NotificationFilter; |
| 48 | import javax.management.NotificationBroadcaster; |
| 49 | import javax.management.NotificationBroadcasterSupport; |
| 50 | import javax.management.MBeanNotificationInfo; |
| 51 | import javax.management.AttributeChangeNotification; |
| 52 | import javax.management.ListenerNotFoundException; |
| 53 | import javax.management.loading.ClassLoaderRepository; |
| 54 | import javax.management.MBeanServerFactory; |
| 55 | |
| 56 | import static com.sun.jmx.defaults.JmxProperties.SNMP_ADAPTOR_LOGGER; |
| 57 | |
| 58 | // JSR 160 import |
| 59 | // |
| 60 | // XXX Revisit: |
| 61 | // used to import com.sun.jmx.snmp.MBeanServerForwarder |
| 62 | // Now using JSR 160 instead. => this is an additional |
| 63 | // dependency to JSR 160. |
| 64 | // |
| 65 | import javax.management.remote.MBeanServerForwarder; |
| 66 | |
| 67 | /** |
| 68 | * Defines generic behavior for the server part of a connector or an adaptor. |
| 69 | * Most connectors or adaptors extend <CODE>CommunicatorServer</CODE> |
| 70 | * and inherit this behavior. Connectors or adaptors that do not fit into |
| 71 | * this model do not extend <CODE>CommunicatorServer</CODE>. |
| 72 | * <p> |
| 73 | * A <CODE>CommunicatorServer</CODE> is an active object, it listens for |
| 74 | * client requests and processes them in its own thread. When necessary, a |
| 75 | * <CODE>CommunicatorServer</CODE> creates other threads to process multiple |
| 76 | * requests concurrently. |
| 77 | * <p> |
| 78 | * A <CODE>CommunicatorServer</CODE> object can be stopped by calling the |
| 79 | * <CODE>stop</CODE> method. When it is stopped, the |
| 80 | * <CODE>CommunicatorServer</CODE> no longer listens to client requests and |
| 81 | * no longer holds any thread or communication resources. |
| 82 | * It can be started again by calling the <CODE>start</CODE> method. |
| 83 | * <p> |
| 84 | * A <CODE>CommunicatorServer</CODE> has a <CODE>State</CODE> attribute |
| 85 | * which reflects its activity. |
| 86 | * <p> |
| 87 | * <TABLE> |
| 88 | * <TR><TH>CommunicatorServer</TH> <TH>State</TH></TR> |
| 89 | * <TR><TD><CODE>stopped</CODE></TD> <TD><CODE>OFFLINE</CODE></TD></TR> |
| 90 | * <TR><TD><CODE>starting</CODE></TD> <TD><CODE>STARTING</CODE></TD></TR> |
| 91 | * <TR><TD><CODE>running</CODE></TD> <TD><CODE>ONLINE</CODE></TD></TR> |
| 92 | * <TR><TD><CODE>stopping</CODE></TD> <TD><CODE>STOPPING</CODE></TD></TR> |
| 93 | * </TABLE> |
| 94 | * <p> |
| 95 | * The <CODE>STARTING</CODE> state marks the transition |
| 96 | * from <CODE>OFFLINE</CODE> to <CODE>ONLINE</CODE>. |
| 97 | * <p> |
| 98 | * The <CODE>STOPPING</CODE> state marks the transition from |
| 99 | * <CODE>ONLINE</CODE> to <CODE>OFFLINE</CODE>. This occurs when the |
| 100 | * <CODE>CommunicatorServer</CODE> is finishing or interrupting active |
| 101 | * requests. |
| 102 | * <p> |
| 103 | * When a <CODE>CommunicatorServer</CODE> is unregistered from the MBeanServer, |
| 104 | * it is stopped automatically. |
| 105 | * <p> |
| 106 | * When the value of the <CODE>State</CODE> attribute changes the |
| 107 | * <CODE>CommunicatorServer</CODE> sends a |
| 108 | * <tt>{@link javax.management.AttributeChangeNotification}</tt> to the |
| 109 | * registered listeners, if any. |
| 110 | * |
| 111 | * <p><b>This API is a Sun Microsystems internal API and is subject |
| 112 | * to change without notice.</b></p> |
| 113 | */ |
| 114 | |
| 115 | public abstract class CommunicatorServer |
| 116 | implements Runnable, MBeanRegistration, NotificationBroadcaster, |
| 117 | CommunicatorServerMBean { |
| 118 | |
| 119 | // |
| 120 | // States of a CommunicatorServer |
| 121 | // |
| 122 | |
| 123 | /** |
| 124 | * Represents an <CODE>ONLINE</CODE> state. |
| 125 | */ |
| 126 | public static final int ONLINE = 0 ; |
| 127 | |
| 128 | /** |
| 129 | * Represents an <CODE>OFFLINE</CODE> state. |
| 130 | */ |
| 131 | public static final int OFFLINE = 1 ; |
| 132 | |
| 133 | /** |
| 134 | * Represents a <CODE>STOPPING</CODE> state. |
| 135 | */ |
| 136 | public static final int STOPPING = 2 ; |
| 137 | |
| 138 | /** |
| 139 | * Represents a <CODE>STARTING</CODE> state. |
| 140 | */ |
| 141 | public static final int STARTING = 3 ; |
| 142 | |
| 143 | // |
| 144 | // Types of connectors. |
| 145 | // |
| 146 | |
| 147 | /** |
| 148 | * Indicates that it is an RMI connector type. |
| 149 | */ |
| 150 | //public static final int RMI_TYPE = 1 ; |
| 151 | |
| 152 | /** |
| 153 | * Indicates that it is an HTTP connector type. |
| 154 | */ |
| 155 | //public static final int HTTP_TYPE = 2 ; |
| 156 | |
| 157 | /** |
| 158 | * Indicates that it is an HTML connector type. |
| 159 | */ |
| 160 | //public static final int HTML_TYPE = 3 ; |
| 161 | |
| 162 | /** |
| 163 | * Indicates that it is an SNMP connector type. |
| 164 | */ |
| 165 | public static final int SNMP_TYPE = 4 ; |
| 166 | |
| 167 | /** |
| 168 | * Indicates that it is an HTTPS connector type. |
| 169 | */ |
| 170 | //public static final int HTTPS_TYPE = 5 ; |
| 171 | |
| 172 | // |
| 173 | // Package variables |
| 174 | // |
| 175 | |
| 176 | /** |
| 177 | * The state of the connector server. |
| 178 | */ |
| 179 | transient volatile int state = OFFLINE ; |
| 180 | |
| 181 | /** |
| 182 | * The object name of the connector server. |
| 183 | * @serial |
| 184 | */ |
| 185 | ObjectName objectName ; |
| 186 | |
| 187 | MBeanServer topMBS; |
| 188 | MBeanServer bottomMBS; |
| 189 | |
| 190 | /** |
| 191 | */ |
| 192 | transient String dbgTag = null ; |
| 193 | |
| 194 | /** |
| 195 | * The maximum number of clients that the CommunicatorServer can |
| 196 | * process concurrently. |
| 197 | * @serial |
| 198 | */ |
| 199 | int maxActiveClientCount = 1 ; |
| 200 | |
| 201 | /** |
| 202 | */ |
| 203 | transient int servedClientCount = 0 ; |
| 204 | |
| 205 | /** |
| 206 | * The host name used by this CommunicatorServer. |
| 207 | * @serial |
| 208 | */ |
| 209 | String host = null ; |
| 210 | |
| 211 | /** |
| 212 | * The port number used by this CommunicatorServer. |
| 213 | * @serial |
| 214 | */ |
| 215 | int port = -1 ; |
| 216 | |
| 217 | |
| 218 | // |
| 219 | // Private fields |
| 220 | // |
| 221 | |
| 222 | /* This object controls access to the "state" and "interrupted" variables. |
| 223 | If held at the same time as the lock on "this", the "this" lock must |
| 224 | be taken first. */ |
| 225 | private transient Object stateLock = new Object(); |
| 226 | |
| 227 | private transient Vector<ClientHandler> |
| 228 | clientHandlerVector = new Vector<ClientHandler>() ; |
| 229 | |
| 230 | private transient Thread fatherThread = Thread.currentThread() ; |
| 231 | private transient Thread mainThread = null ; |
| 232 | |
| 233 | private volatile boolean stopRequested = false ; |
| 234 | private boolean interrupted = false; |
| 235 | private transient Exception startException = null; |
| 236 | |
| 237 | // Notifs count, broadcaster and info |
| 238 | private transient long notifCount = 0; |
| 239 | private transient NotificationBroadcasterSupport notifBroadcaster = |
| 240 | new NotificationBroadcasterSupport(); |
| 241 | private transient MBeanNotificationInfo[] notifInfos = null; |
| 242 | |
| 243 | |
| 244 | /** |
| 245 | * Instantiates a <CODE>CommunicatorServer</CODE>. |
| 246 | * |
| 247 | * @param connectorType Indicates the connector type. Possible values are: |
| 248 | * SNMP_TYPE. |
| 249 | * |
| 250 | * @exception <CODE>java.lang.IllegalArgumentException</CODE> |
| 251 | * This connector type is not correct. |
| 252 | */ |
| 253 | public CommunicatorServer(int connectorType) |
| 254 | throws IllegalArgumentException { |
| 255 | switch (connectorType) { |
| 256 | case SNMP_TYPE : |
| 257 | //No op. int Type deciding debugging removed. |
| 258 | break; |
| 259 | default: |
| 260 | throw new IllegalArgumentException("Invalid connector Type") ; |
| 261 | } |
| 262 | dbgTag = makeDebugTag() ; |
| 263 | } |
| 264 | |
| 265 | protected Thread createMainThread() { |
| 266 | return new Thread (this, makeThreadName()); |
| 267 | } |
| 268 | |
| 269 | /** |
| 270 | * Starts this <CODE>CommunicatorServer</CODE>. |
| 271 | * <p> |
| 272 | * Has no effect if this <CODE>CommunicatorServer</CODE> is |
| 273 | * <CODE>ONLINE</CODE> or <CODE>STOPPING</CODE>. |
| 274 | * @param timeout Time in ms to wait for the connector to start. |
| 275 | * If <code>timeout</code> is positive, wait for at most |
| 276 | * the specified time. An infinite timeout can be specified |
| 277 | * by passing a <code>timeout</code> value equals |
| 278 | * <code>Long.MAX_VALUE</code>. In that case the method |
| 279 | * will wait until the connector starts or fails to start. |
| 280 | * If timeout is negative or zero, returns as soon as possible |
| 281 | * without waiting. |
| 282 | * @exception CommunicationException if the connectors fails to start. |
| 283 | * @exception InterruptedException if the thread is interrupted or the |
| 284 | * timeout expires. |
| 285 | */ |
| 286 | public void start(long timeout) |
| 287 | throws CommunicationException, InterruptedException { |
| 288 | boolean start; |
| 289 | |
| 290 | synchronized (stateLock) { |
| 291 | if (state == STOPPING) { |
| 292 | // Fix for bug 4352451: |
| 293 | // "java.net.BindException: Address in use". |
| 294 | waitState(OFFLINE, 60000); |
| 295 | } |
| 296 | start = (state == OFFLINE); |
| 297 | if (start) { |
| 298 | changeState(STARTING); |
| 299 | stopRequested = false; |
| 300 | interrupted = false; |
| 301 | startException = null; |
| 302 | } |
| 303 | } |
| 304 | |
| 305 | if (!start) { |
| 306 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 307 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 308 | "start","Connector is not OFFLINE"); |
| 309 | } |
| 310 | return; |
| 311 | } |
| 312 | |
| 313 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 314 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 315 | "start","--> Start connector "); |
| 316 | } |
| 317 | |
| 318 | mainThread = createMainThread(); |
| 319 | |
| 320 | mainThread.start() ; |
| 321 | |
| 322 | if (timeout > 0) waitForStart(timeout); |
| 323 | } |
| 324 | |
| 325 | /** |
| 326 | * Starts this <CODE>CommunicatorServer</CODE>. |
| 327 | * <p> |
| 328 | * Has no effect if this <CODE>CommunicatorServer</CODE> is |
| 329 | * <CODE>ONLINE</CODE> or <CODE>STOPPING</CODE>. |
| 330 | */ |
| 331 | public void start() { |
| 332 | try { |
| 333 | start(0); |
| 334 | } catch (InterruptedException x) { |
| 335 | // cannot happen because of `0' |
| 336 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 337 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 338 | "start","interrupted", x); |
| 339 | } |
| 340 | } |
| 341 | } |
| 342 | |
| 343 | /** |
| 344 | * Stops this <CODE>CommunicatorServer</CODE>. |
| 345 | * <p> |
| 346 | * Has no effect if this <CODE>CommunicatorServer</CODE> is |
| 347 | * <CODE>OFFLINE</CODE> or <CODE>STOPPING</CODE>. |
| 348 | */ |
| 349 | public void stop() { |
| 350 | synchronized (stateLock) { |
| 351 | if (state == OFFLINE || state == STOPPING) { |
| 352 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 353 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 354 | "stop","Connector is not ONLINE"); |
| 355 | } |
| 356 | return; |
| 357 | } |
| 358 | changeState(STOPPING); |
| 359 | // |
| 360 | // Stop the connector thread |
| 361 | // |
| 362 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 363 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 364 | "stop","Interrupt main thread"); |
| 365 | } |
| 366 | stopRequested = true ; |
| 367 | if (!interrupted) { |
| 368 | interrupted = true; |
| 369 | mainThread.interrupt(); |
| 370 | } |
| 371 | } |
| 372 | |
| 373 | // |
| 374 | // Call terminate on each active client handler |
| 375 | // |
| 376 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 377 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 378 | "stop","terminateAllClient"); |
| 379 | } |
| 380 | terminateAllClient() ; |
| 381 | |
| 382 | // ---------------------- |
| 383 | // changeState |
| 384 | // ---------------------- |
| 385 | synchronized (stateLock) { |
| 386 | if (state == STARTING) |
| 387 | changeState(OFFLINE); |
| 388 | } |
| 389 | } |
| 390 | |
| 391 | /** |
| 392 | * Tests whether the <CODE>CommunicatorServer</CODE> is active. |
| 393 | * |
| 394 | * @return True if connector is <CODE>ONLINE</CODE>; false otherwise. |
| 395 | */ |
| 396 | public boolean isActive() { |
| 397 | synchronized (stateLock) { |
| 398 | return (state == ONLINE); |
| 399 | } |
| 400 | } |
| 401 | |
| 402 | /** |
| 403 | * <p>Waits until either the State attribute of this MBean equals the |
| 404 | * specified <VAR>wantedState</VAR> parameter, |
| 405 | * or the specified <VAR>timeOut</VAR> has elapsed. |
| 406 | * The method <CODE>waitState</CODE> returns with a boolean value |
| 407 | * indicating whether the specified <VAR>wantedState</VAR> parameter |
| 408 | * equals the value of this MBean's State attribute at the time the method |
| 409 | * terminates.</p> |
| 410 | * |
| 411 | * <p>Two special cases for the <VAR>timeOut</VAR> parameter value are:</p> |
| 412 | * <UL><LI> if <VAR>timeOut</VAR> is negative then <CODE>waitState</CODE> |
| 413 | * returns immediately (i.e. does not wait at all),</LI> |
| 414 | * <LI> if <VAR>timeOut</VAR> equals zero then <CODE>waitState</CODE> |
| 415 | * waits untill the value of this MBean's State attribute |
| 416 | * is the same as the <VAR>wantedState</VAR> parameter (i.e. will wait |
| 417 | * indefinitely if this condition is never met).</LI></UL> |
| 418 | * |
| 419 | * @param wantedState The value of this MBean's State attribute to wait |
| 420 | * for. <VAR>wantedState</VAR> can be one of: |
| 421 | * <ul> |
| 422 | * <li><CODE>CommunicatorServer.OFFLINE</CODE>,</li> |
| 423 | * <li><CODE>CommunicatorServer.ONLINE</CODE>,</li> |
| 424 | * <li><CODE>CommunicatorServer.STARTING</CODE>,</li> |
| 425 | * <li><CODE>CommunicatorServer.STOPPING</CODE>.</li> |
| 426 | * </ul> |
| 427 | * @param timeOut The maximum time to wait for, in milliseconds, |
| 428 | * if positive. |
| 429 | * Infinite time out if 0, or no waiting at all if negative. |
| 430 | * |
| 431 | * @return true if the value of this MBean's State attribute is the |
| 432 | * same as the <VAR>wantedState</VAR> parameter; false otherwise. |
| 433 | */ |
| 434 | public boolean waitState(int wantedState, long timeOut) { |
| 435 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 436 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 437 | "waitState", wantedState + "(0on,1off,2st) TO=" + timeOut + |
| 438 | " ; current state = " + getStateString()); |
| 439 | } |
| 440 | |
| 441 | long endTime = 0; |
| 442 | if (timeOut > 0) |
| 443 | endTime = System.currentTimeMillis() + timeOut; |
| 444 | |
| 445 | synchronized (stateLock) { |
| 446 | while (state != wantedState) { |
| 447 | if (timeOut < 0) { |
| 448 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 449 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 450 | "waitState", "timeOut < 0, return without wait"); |
| 451 | } |
| 452 | return false; |
| 453 | } else { |
| 454 | try { |
| 455 | if (timeOut > 0) { |
| 456 | long toWait = endTime - System.currentTimeMillis(); |
| 457 | if (toWait <= 0) { |
| 458 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 459 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 460 | "waitState", "timed out"); |
| 461 | } |
| 462 | return false; |
| 463 | } |
| 464 | stateLock.wait(toWait); |
| 465 | } else { // timeOut == 0 |
| 466 | stateLock.wait(); |
| 467 | } |
| 468 | } catch (InterruptedException e) { |
| 469 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 470 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 471 | "waitState", "wait interrupted"); |
| 472 | } |
| 473 | return (state == wantedState); |
| 474 | } |
| 475 | } |
| 476 | } |
| 477 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 478 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 479 | "waitState","returning in desired state"); |
| 480 | } |
| 481 | return true; |
| 482 | } |
| 483 | } |
| 484 | |
| 485 | /** |
| 486 | * <p>Waits until the communicator is started or timeout expires. |
| 487 | * |
| 488 | * @param timeout Time in ms to wait for the connector to start. |
| 489 | * If <code>timeout</code> is positive, wait for at most |
| 490 | * the specified time. An infinite timeout can be specified |
| 491 | * by passing a <code>timeout</code> value equals |
| 492 | * <code>Long.MAX_VALUE</code>. In that case the method |
| 493 | * will wait until the connector starts or fails to start. |
| 494 | * If timeout is negative or zero, returns as soon as possible |
| 495 | * without waiting. |
| 496 | * |
| 497 | * @exception CommunicationException if the connectors fails to start. |
| 498 | * @exception InterruptedException if the thread is interrupted or the |
| 499 | * timeout expires. |
| 500 | * |
| 501 | */ |
| 502 | private void waitForStart(long timeout) |
| 503 | throws CommunicationException, InterruptedException { |
| 504 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 505 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 506 | "waitForStart", "Timeout=" + timeout + |
| 507 | " ; current state = " + getStateString()); |
| 508 | } |
| 509 | |
| 510 | final long startTime = System.currentTimeMillis(); |
| 511 | |
| 512 | synchronized (stateLock) { |
| 513 | while (state == STARTING) { |
| 514 | // Time elapsed since startTime... |
| 515 | // |
| 516 | final long elapsed = System.currentTimeMillis() - startTime; |
| 517 | |
| 518 | // wait for timeout - elapsed. |
| 519 | // A timeout of Long.MAX_VALUE is equivalent to something |
| 520 | // like 292271023 years - which is pretty close to |
| 521 | // forever as far as we are concerned ;-) |
| 522 | // |
| 523 | final long remainingTime = timeout-elapsed; |
| 524 | |
| 525 | // If remainingTime is negative, the timeout has elapsed. |
| 526 | // |
| 527 | if (remainingTime < 0) { |
| 528 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 529 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 530 | "waitForStart", "timeout < 0, return without wait"); |
| 531 | } |
| 532 | throw new InterruptedException("Timeout expired"); |
| 533 | } |
| 534 | |
| 535 | // We're going to wait until someone notifies on the |
| 536 | // the stateLock object, or until the timeout expires, |
| 537 | // or until the thread is interrupted. |
| 538 | // |
| 539 | try { |
| 540 | stateLock.wait(remainingTime); |
| 541 | } catch (InterruptedException e) { |
| 542 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 543 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 544 | "waitForStart", "wait interrupted"); |
| 545 | } |
| 546 | |
| 547 | // If we are now ONLINE, then no need to rethrow the |
| 548 | // exception... we're simply going to exit the while |
| 549 | // loop. Otherwise, throw the InterruptedException. |
| 550 | // |
| 551 | if (state != ONLINE) throw e; |
| 552 | } |
| 553 | } |
| 554 | |
| 555 | // We're no longer in STARTING state |
| 556 | // |
| 557 | if (state == ONLINE) { |
| 558 | // OK, we're started, everything went fine, just return |
| 559 | // |
| 560 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 561 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 562 | "waitForStart", "started"); |
| 563 | } |
| 564 | return; |
| 565 | } else if (startException instanceof CommunicationException) { |
| 566 | // There was some exception during the starting phase. |
| 567 | // Cast and throw... |
| 568 | // |
| 569 | throw (CommunicationException)startException; |
| 570 | } else if (startException instanceof InterruptedException) { |
| 571 | // There was some exception during the starting phase. |
| 572 | // Cast and throw... |
| 573 | // |
| 574 | throw (InterruptedException)startException; |
| 575 | } else if (startException != null) { |
| 576 | // There was some exception during the starting phase. |
| 577 | // Wrap and throw... |
| 578 | // |
| 579 | throw new CommunicationException(startException, |
| 580 | "Failed to start: "+ |
| 581 | startException); |
| 582 | } else { |
| 583 | // We're not ONLINE, and there's no exception... |
| 584 | // Something went wrong but we don't know what... |
| 585 | // |
| 586 | throw new CommunicationException("Failed to start: state is "+ |
| 587 | getStringForState(state)); |
| 588 | } |
| 589 | } |
| 590 | } |
| 591 | |
| 592 | /** |
| 593 | * Gets the state of this <CODE>CommunicatorServer</CODE> as an integer. |
| 594 | * |
| 595 | * @return <CODE>ONLINE</CODE>, <CODE>OFFLINE</CODE>, |
| 596 | * <CODE>STARTING</CODE> or <CODE>STOPPING</CODE>. |
| 597 | */ |
| 598 | public int getState() { |
| 599 | synchronized (stateLock) { |
| 600 | return state ; |
| 601 | } |
| 602 | } |
| 603 | |
| 604 | /** |
| 605 | * Gets the state of this <CODE>CommunicatorServer</CODE> as a string. |
| 606 | * |
| 607 | * @return One of the strings "ONLINE", "OFFLINE", "STARTING" or |
| 608 | * "STOPPING". |
| 609 | */ |
| 610 | public String getStateString() { |
| 611 | return getStringForState(state) ; |
| 612 | } |
| 613 | |
| 614 | /** |
| 615 | * Gets the host name used by this <CODE>CommunicatorServer</CODE>. |
| 616 | * |
| 617 | * @return The host name used by this <CODE>CommunicatorServer</CODE>. |
| 618 | */ |
| 619 | public String getHost() { |
| 620 | try { |
| 621 | host = InetAddress.getLocalHost().getHostName(); |
| 622 | } catch (Exception e) { |
| 623 | host = "Unknown host"; |
| 624 | } |
| 625 | return host ; |
| 626 | } |
| 627 | |
| 628 | /** |
| 629 | * Gets the port number used by this <CODE>CommunicatorServer</CODE>. |
| 630 | * |
| 631 | * @return The port number used by this <CODE>CommunicatorServer</CODE>. |
| 632 | */ |
| 633 | public int getPort() { |
| 634 | synchronized (stateLock) { |
| 635 | return port ; |
| 636 | } |
| 637 | } |
| 638 | |
| 639 | /** |
| 640 | * Sets the port number used by this <CODE>CommunicatorServer</CODE>. |
| 641 | * |
| 642 | * @param port The port number used by this |
| 643 | * <CODE>CommunicatorServer</CODE>. |
| 644 | * |
| 645 | * @exception java.lang.IllegalStateException This method has been invoked |
| 646 | * while the communicator was ONLINE or STARTING. |
| 647 | */ |
| 648 | public void setPort(int port) throws java.lang.IllegalStateException { |
| 649 | synchronized (stateLock) { |
| 650 | if ((state == ONLINE) || (state == STARTING)) |
| 651 | throw new IllegalStateException("Stop server before " + |
| 652 | "carrying out this operation"); |
| 653 | this.port = port; |
| 654 | dbgTag = makeDebugTag(); |
| 655 | } |
| 656 | } |
| 657 | |
| 658 | /** |
| 659 | * Gets the protocol being used by this <CODE>CommunicatorServer</CODE>. |
| 660 | * @return The protocol as a string. |
| 661 | */ |
| 662 | public abstract String getProtocol() ; |
| 663 | |
| 664 | /** |
| 665 | * Gets the number of clients that have been processed by this |
| 666 | * <CODE>CommunicatorServer</CODE> since its creation. |
| 667 | * |
| 668 | * @return The number of clients handled by this |
| 669 | * <CODE>CommunicatorServer</CODE> |
| 670 | * since its creation. This counter is not reset by the |
| 671 | * <CODE>stop</CODE> method. |
| 672 | */ |
| 673 | int getServedClientCount() { |
| 674 | return servedClientCount ; |
| 675 | } |
| 676 | |
| 677 | /** |
| 678 | * Gets the number of clients currently being processed by this |
| 679 | * <CODE>CommunicatorServer</CODE>. |
| 680 | * |
| 681 | * @return The number of clients currently being processed by this |
| 682 | * <CODE>CommunicatorServer</CODE>. |
| 683 | */ |
| 684 | int getActiveClientCount() { |
| 685 | int result = clientHandlerVector.size() ; |
| 686 | return result ; |
| 687 | } |
| 688 | |
| 689 | /** |
| 690 | * Gets the maximum number of clients that this |
| 691 | * <CODE>CommunicatorServer</CODE> can process concurrently. |
| 692 | * |
| 693 | * @return The maximum number of clients that this |
| 694 | * <CODE>CommunicatorServer</CODE> can |
| 695 | * process concurrently. |
| 696 | */ |
| 697 | int getMaxActiveClientCount() { |
| 698 | return maxActiveClientCount ; |
| 699 | } |
| 700 | |
| 701 | /** |
| 702 | * Sets the maximum number of clients this |
| 703 | * <CODE>CommunicatorServer</CODE> can process concurrently. |
| 704 | * |
| 705 | * @param c The number of clients. |
| 706 | * |
| 707 | * @exception java.lang.IllegalStateException This method has been invoked |
| 708 | * while the communicator was ONLINE or STARTING. |
| 709 | */ |
| 710 | void setMaxActiveClientCount(int c) |
| 711 | throws java.lang.IllegalStateException { |
| 712 | synchronized (stateLock) { |
| 713 | if ((state == ONLINE) || (state == STARTING)) { |
| 714 | throw new IllegalStateException( |
| 715 | "Stop server before carrying out this operation"); |
| 716 | } |
| 717 | maxActiveClientCount = c ; |
| 718 | } |
| 719 | } |
| 720 | |
| 721 | /** |
| 722 | * For SNMP Runtime internal use only. |
| 723 | */ |
| 724 | void notifyClientHandlerCreated(ClientHandler h) { |
| 725 | clientHandlerVector.addElement(h) ; |
| 726 | } |
| 727 | |
| 728 | /** |
| 729 | * For SNMP Runtime internal use only. |
| 730 | */ |
| 731 | synchronized void notifyClientHandlerDeleted(ClientHandler h) { |
| 732 | clientHandlerVector.removeElement(h); |
| 733 | notifyAll(); |
| 734 | } |
| 735 | |
| 736 | /** |
| 737 | * The number of times the communicator server will attempt |
| 738 | * to bind before giving up. |
| 739 | **/ |
| 740 | protected int getBindTries() { |
| 741 | return 50; |
| 742 | } |
| 743 | |
| 744 | /** |
| 745 | * The delay, in ms, during which the communicator server will sleep before |
| 746 | * attempting to bind again. |
| 747 | **/ |
| 748 | protected long getBindSleepTime() { |
| 749 | return 100; |
| 750 | } |
| 751 | |
| 752 | /** |
| 753 | * For SNMP Runtime internal use only. |
| 754 | * <p> |
| 755 | * The <CODE>run</CODE> method executed by this connector's main thread. |
| 756 | */ |
| 757 | public void run() { |
| 758 | |
| 759 | // Fix jaw.00667.B |
| 760 | // It seems that the init of "i" and "success" |
| 761 | // need to be done outside the "try" clause... |
| 762 | // A bug in Java 2 production release ? |
| 763 | // |
| 764 | int i = 0; |
| 765 | boolean success = false; |
| 766 | |
| 767 | // ---------------------- |
| 768 | // Bind |
| 769 | // ---------------------- |
| 770 | try { |
| 771 | // Fix for bug 4352451: "java.net.BindException: Address in use". |
| 772 | // |
| 773 | final int bindRetries = getBindTries(); |
| 774 | final long sleepTime = getBindSleepTime(); |
| 775 | while (i < bindRetries && !success) { |
| 776 | try { |
| 777 | // Try socket connection. |
| 778 | // |
| 779 | doBind(); |
| 780 | success = true; |
| 781 | } catch (CommunicationException ce) { |
| 782 | i++; |
| 783 | try { |
| 784 | Thread.sleep(sleepTime); |
| 785 | } catch (InterruptedException ie) { |
| 786 | throw ie; |
| 787 | } |
| 788 | } |
| 789 | } |
| 790 | // Retry last time to get correct exception. |
| 791 | // |
| 792 | if (!success) { |
| 793 | // Try socket connection. |
| 794 | // |
| 795 | doBind(); |
| 796 | } |
| 797 | |
| 798 | } catch(Exception x) { |
| 799 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINEST)) { |
| 800 | SNMP_ADAPTOR_LOGGER.logp(Level.FINEST, dbgTag, |
| 801 | "run", "Got unexpected exception", x); |
| 802 | } |
| 803 | synchronized(stateLock) { |
| 804 | startException = x; |
| 805 | changeState(OFFLINE); |
| 806 | } |
| 807 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 808 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 809 | "run","State is OFFLINE"); |
| 810 | } |
| 811 | doError(x); |
| 812 | return; |
| 813 | } |
| 814 | |
| 815 | try { |
| 816 | // ---------------------- |
| 817 | // State change |
| 818 | // ---------------------- |
| 819 | changeState(ONLINE) ; |
| 820 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 821 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 822 | "run","State is ONLINE"); |
| 823 | } |
| 824 | |
| 825 | // ---------------------- |
| 826 | // Main loop |
| 827 | // ---------------------- |
| 828 | while (!stopRequested) { |
| 829 | servedClientCount++; |
| 830 | doReceive() ; |
| 831 | waitIfTooManyClients() ; |
| 832 | doProcess() ; |
| 833 | } |
| 834 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 835 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 836 | "run","Stop has been requested"); |
| 837 | } |
| 838 | |
| 839 | } catch(InterruptedException x) { |
| 840 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINEST)) { |
| 841 | SNMP_ADAPTOR_LOGGER.logp(Level.FINEST, dbgTag, |
| 842 | "run","Interrupt caught"); |
| 843 | } |
| 844 | changeState(STOPPING); |
| 845 | } catch(Exception x) { |
| 846 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINEST)) { |
| 847 | SNMP_ADAPTOR_LOGGER.logp(Level.FINEST, dbgTag, |
| 848 | "run","Got unexpected exception", x); |
| 849 | } |
| 850 | changeState(STOPPING); |
| 851 | } finally { |
| 852 | synchronized (stateLock) { |
| 853 | interrupted = true; |
| 854 | Thread.currentThread().interrupted(); |
| 855 | } |
| 856 | |
| 857 | // ---------------------- |
| 858 | // unBind |
| 859 | // ---------------------- |
| 860 | try { |
| 861 | doUnbind() ; |
| 862 | waitClientTermination() ; |
| 863 | changeState(OFFLINE); |
| 864 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 865 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 866 | "run","State is OFFLINE"); |
| 867 | } |
| 868 | } catch(Exception x) { |
| 869 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINEST)) { |
| 870 | SNMP_ADAPTOR_LOGGER.logp(Level.FINEST, dbgTag, |
| 871 | "run","Got unexpected exception", x); |
| 872 | } |
| 873 | changeState(OFFLINE); |
| 874 | } |
| 875 | |
| 876 | } |
| 877 | } |
| 878 | |
| 879 | /** |
| 880 | */ |
| 881 | protected abstract void doError(Exception e) throws CommunicationException; |
| 882 | |
| 883 | // |
| 884 | // To be defined by the subclass. |
| 885 | // |
| 886 | // Each method below is called by run() and must be subclassed. |
| 887 | // If the method sends an exception (Communication or Interrupt), this |
| 888 | // will end up the run() method and switch the connector offline. |
| 889 | // |
| 890 | // If it is a CommunicationException, run() will call |
| 891 | // Debug.printException(). |
| 892 | // |
| 893 | // All these methods should propagate the InterruptedException to inform |
| 894 | // run() that the connector must be switch OFFLINE. |
| 895 | // |
| 896 | // |
| 897 | // |
| 898 | // doBind() should do all what is needed before calling doReceive(). |
| 899 | // If doBind() throws an exception, doUnbind() is not to be called |
| 900 | // and run() ends up. |
| 901 | // |
| 902 | |
| 903 | /** |
| 904 | */ |
| 905 | protected abstract void doBind() |
| 906 | throws CommunicationException, InterruptedException ; |
| 907 | |
| 908 | /** |
| 909 | * <CODE>doReceive()</CODE> should block until a client is available. |
| 910 | * If this method throws an exception, <CODE>doProcess()</CODE> is not |
| 911 | * called but <CODE>doUnbind()</CODE> is called then <CODE>run()</CODE> |
| 912 | * stops. |
| 913 | */ |
| 914 | protected abstract void doReceive() |
| 915 | throws CommunicationException, InterruptedException ; |
| 916 | |
| 917 | /** |
| 918 | * <CODE>doProcess()</CODE> is called after <CODE>doReceive()</CODE>: |
| 919 | * it should process the requests of the incoming client. |
| 920 | * If it throws an exception, <CODE>doUnbind()</CODE> is called and |
| 921 | * <CODE>run()</CODE> stops. |
| 922 | */ |
| 923 | protected abstract void doProcess() |
| 924 | throws CommunicationException, InterruptedException ; |
| 925 | |
| 926 | /** |
| 927 | * <CODE>doUnbind()</CODE> is called whenever the connector goes |
| 928 | * <CODE>OFFLINE</CODE>, except if <CODE>doBind()</CODE> has thrown an |
| 929 | * exception. |
| 930 | */ |
| 931 | protected abstract void doUnbind() |
| 932 | throws CommunicationException, InterruptedException ; |
| 933 | |
| 934 | /** |
| 935 | * Get the <code>MBeanServer</code> object to which incoming requests are |
| 936 | * sent. This is either the MBean server in which this connector is |
| 937 | * registered, or an <code>MBeanServerForwarder</code> leading to that |
| 938 | * server. |
| 939 | */ |
| 940 | public synchronized MBeanServer getMBeanServer() { |
| 941 | return topMBS; |
| 942 | } |
| 943 | |
| 944 | /** |
| 945 | * Set the <code>MBeanServer</code> object to which incoming |
| 946 | * requests are sent. This must be either the MBean server in |
| 947 | * which this connector is registered, or an |
| 948 | * <code>MBeanServerForwarder</code> leading to that server. An |
| 949 | * <code>MBeanServerForwarder</code> <code>mbsf</code> leads to an |
| 950 | * MBean server <code>mbs</code> if |
| 951 | * <code>mbsf.getMBeanServer()</code> is either <code>mbs</code> |
| 952 | * or an <code>MBeanServerForwarder</code> leading to |
| 953 | * <code>mbs</code>. |
| 954 | * |
| 955 | * @exception IllegalArgumentException if <code>newMBS</code> is neither |
| 956 | * the MBean server in which this connector is registered nor an |
| 957 | * <code>MBeanServerForwarder</code> leading to that server. |
| 958 | * |
| 959 | * @exception IllegalStateException This method has been invoked |
| 960 | * while the communicator was ONLINE or STARTING. |
| 961 | */ |
| 962 | public synchronized void setMBeanServer(MBeanServer newMBS) |
| 963 | throws IllegalArgumentException, IllegalStateException { |
| 964 | synchronized (stateLock) { |
| 965 | if (state == ONLINE || state == STARTING) |
| 966 | throw new IllegalStateException("Stop server before " + |
| 967 | "carrying out this operation"); |
| 968 | } |
| 969 | final String error = |
| 970 | "MBeanServer argument must be MBean server where this " + |
| 971 | "server is registered, or an MBeanServerForwarder " + |
| 972 | "leading to that server"; |
| 973 | Vector<MBeanServer> seenMBS = new Vector<MBeanServer>(); |
| 974 | for (MBeanServer mbs = newMBS; |
| 975 | mbs != bottomMBS; |
| 976 | mbs = ((MBeanServerForwarder) mbs).getMBeanServer()) { |
| 977 | if (!(mbs instanceof MBeanServerForwarder)) |
| 978 | throw new IllegalArgumentException(error); |
| 979 | if (seenMBS.contains(mbs)) |
| 980 | throw new IllegalArgumentException("MBeanServerForwarder " + |
| 981 | "loop"); |
| 982 | seenMBS.addElement(mbs); |
| 983 | } |
| 984 | topMBS = newMBS; |
| 985 | } |
| 986 | |
| 987 | // |
| 988 | // To be called by the subclass if needed |
| 989 | // |
| 990 | /** |
| 991 | * For internal use only. |
| 992 | */ |
| 993 | ObjectName getObjectName() { |
| 994 | return objectName ; |
| 995 | } |
| 996 | |
| 997 | /** |
| 998 | * For internal use only. |
| 999 | */ |
| 1000 | void changeState(int newState) { |
| 1001 | int oldState; |
| 1002 | synchronized (stateLock) { |
| 1003 | if (state == newState) |
| 1004 | return; |
| 1005 | oldState = state; |
| 1006 | state = newState; |
| 1007 | stateLock.notifyAll(); |
| 1008 | } |
| 1009 | sendStateChangeNotification(oldState, newState); |
| 1010 | } |
| 1011 | |
| 1012 | /** |
| 1013 | * Returns the string used in debug traces. |
| 1014 | */ |
| 1015 | String makeDebugTag() { |
| 1016 | return "CommunicatorServer["+ getProtocol() + ":" + getPort() + "]" ; |
| 1017 | } |
| 1018 | |
| 1019 | /** |
| 1020 | * Returns the string used to name the connector thread. |
| 1021 | */ |
| 1022 | String makeThreadName() { |
| 1023 | String result ; |
| 1024 | |
| 1025 | if (objectName == null) |
| 1026 | result = "CommunicatorServer" ; |
| 1027 | else |
| 1028 | result = objectName.toString() ; |
| 1029 | |
| 1030 | return result ; |
| 1031 | } |
| 1032 | |
| 1033 | /** |
| 1034 | * This method blocks if there are too many active clients. |
| 1035 | * Call to <CODE>wait()</CODE> is terminated when a client handler |
| 1036 | * thread calls <CODE>notifyClientHandlerDeleted(this)</CODE> ; |
| 1037 | */ |
| 1038 | private synchronized void waitIfTooManyClients() |
| 1039 | throws InterruptedException { |
| 1040 | while (getActiveClientCount() >= maxActiveClientCount) { |
| 1041 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 1042 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 1043 | "waitIfTooManyClients","Waiting for a client to terminate"); |
| 1044 | } |
| 1045 | wait(); |
| 1046 | } |
| 1047 | } |
| 1048 | |
| 1049 | /** |
| 1050 | * This method blocks until there is no more active client. |
| 1051 | */ |
| 1052 | private void waitClientTermination() { |
| 1053 | int s = clientHandlerVector.size() ; |
| 1054 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 1055 | if (s >= 1) { |
| 1056 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 1057 | "waitClientTermination","waiting for " + |
| 1058 | s + " clients to terminate"); |
| 1059 | } |
| 1060 | } |
| 1061 | |
| 1062 | // The ClientHandler will remove themselves from the |
| 1063 | // clientHandlerVector at the end of their run() method, by |
| 1064 | // calling notifyClientHandlerDeleted(). |
| 1065 | // Since the clientHandlerVector is modified by the ClientHandler |
| 1066 | // threads we must avoid using Enumeration or Iterator to loop |
| 1067 | // over this array. We must also take care of NoSuchElementException |
| 1068 | // which could be thrown if the last ClientHandler removes itself |
| 1069 | // between the call to clientHandlerVector.isEmpty() and the call |
| 1070 | // to clientHandlerVector.firstElement(). |
| 1071 | // What we *MUST NOT DO* is locking the clientHandlerVector, because |
| 1072 | // this would most probably cause a deadlock. |
| 1073 | // |
| 1074 | while (! clientHandlerVector.isEmpty()) { |
| 1075 | try { |
| 1076 | clientHandlerVector.firstElement().join(); |
| 1077 | } catch (NoSuchElementException x) { |
| 1078 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 1079 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 1080 | "waitClientTermination","No elements left", x); |
| 1081 | } |
| 1082 | } |
| 1083 | } |
| 1084 | |
| 1085 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 1086 | if (s >= 1) { |
| 1087 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 1088 | "waitClientTermination","Ok, let's go..."); |
| 1089 | } |
| 1090 | } |
| 1091 | } |
| 1092 | |
| 1093 | /** |
| 1094 | * Call <CODE>interrupt()</CODE> on each pending client. |
| 1095 | */ |
| 1096 | private void terminateAllClient() { |
| 1097 | final int s = clientHandlerVector.size() ; |
| 1098 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 1099 | if (s >= 1) { |
| 1100 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 1101 | "terminateAllClient","Interrupting " + s + " clients"); |
| 1102 | } |
| 1103 | } |
| 1104 | |
| 1105 | // The ClientHandler will remove themselves from the |
| 1106 | // clientHandlerVector at the end of their run() method, by |
| 1107 | // calling notifyClientHandlerDeleted(). |
| 1108 | // Since the clientHandlerVector is modified by the ClientHandler |
| 1109 | // threads we must avoid using Enumeration or Iterator to loop |
| 1110 | // over this array. |
| 1111 | // We cannot use the same logic here than in waitClientTermination() |
| 1112 | // because there is no guarantee that calling interrupt() on the |
| 1113 | // ClientHandler will actually terminate the ClientHandler. |
| 1114 | // Since we do not want to wait for the actual ClientHandler |
| 1115 | // termination, we cannot simply loop over the array until it is |
| 1116 | // empty (this might result in calling interrupt() endlessly on |
| 1117 | // the same client handler. So what we do is simply take a snapshot |
| 1118 | // copy of the vector and loop over the copy. |
| 1119 | // What we *MUST NOT DO* is locking the clientHandlerVector, because |
| 1120 | // this would most probably cause a deadlock. |
| 1121 | // |
| 1122 | final ClientHandler[] handlers = |
| 1123 | clientHandlerVector.toArray(new ClientHandler[0]); |
| 1124 | for (ClientHandler h : handlers) { |
| 1125 | try { |
| 1126 | h.interrupt() ; |
| 1127 | } catch (Exception x) { |
| 1128 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINER)) { |
| 1129 | SNMP_ADAPTOR_LOGGER.logp(Level.FINER, dbgTag, |
| 1130 | "terminateAllClient", |
| 1131 | "Failed to interrupt pending request. " + |
| 1132 | "Ignore the exception.", x); |
| 1133 | } |
| 1134 | } |
| 1135 | } |
| 1136 | } |
| 1137 | |
| 1138 | /** |
| 1139 | * Controls the way the CommunicatorServer service is deserialized. |
| 1140 | */ |
| 1141 | private void readObject(ObjectInputStream stream) |
| 1142 | throws IOException, ClassNotFoundException { |
| 1143 | |
| 1144 | // Call the default deserialization of the object. |
| 1145 | // |
| 1146 | stream.defaultReadObject(); |
| 1147 | |
| 1148 | // Call the specific initialization for the CommunicatorServer service. |
| 1149 | // This is for transient structures to be initialized to specific |
| 1150 | // default values. |
| 1151 | // |
| 1152 | stateLock = new Object(); |
| 1153 | state = OFFLINE; |
| 1154 | stopRequested = false; |
| 1155 | servedClientCount = 0; |
| 1156 | clientHandlerVector = new Vector<ClientHandler>(); |
| 1157 | fatherThread = Thread.currentThread(); |
| 1158 | mainThread = null; |
| 1159 | notifCount = 0; |
| 1160 | notifInfos = null; |
| 1161 | notifBroadcaster = new NotificationBroadcasterSupport(); |
| 1162 | dbgTag = makeDebugTag(); |
| 1163 | } |
| 1164 | |
| 1165 | |
| 1166 | // |
| 1167 | // NotificationBroadcaster |
| 1168 | // |
| 1169 | |
| 1170 | /** |
| 1171 | * Adds a listener for the notifications emitted by this |
| 1172 | * CommunicatorServer. |
| 1173 | * There is only one type of notifications sent by the CommunicatorServer: |
| 1174 | * they are <tt>{@link javax.management.AttributeChangeNotification}</tt>, |
| 1175 | * sent when the <tt>State</tt> attribute of this CommunicatorServer |
| 1176 | * changes. |
| 1177 | * |
| 1178 | * @param listener The listener object which will handle the emitted |
| 1179 | * notifications. |
| 1180 | * @param filter The filter object. If filter is null, no filtering |
| 1181 | * will be performed before handling notifications. |
| 1182 | * @param handback An object which will be sent back unchanged to the |
| 1183 | * listener when a notification is emitted. |
| 1184 | * |
| 1185 | * @exception IllegalArgumentException Listener parameter is null. |
| 1186 | */ |
| 1187 | public void addNotificationListener(NotificationListener listener, |
| 1188 | NotificationFilter filter, |
| 1189 | Object handback) |
| 1190 | throws java.lang.IllegalArgumentException { |
| 1191 | |
| 1192 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINEST)) { |
| 1193 | SNMP_ADAPTOR_LOGGER.logp(Level.FINEST, dbgTag, |
| 1194 | "addNotificationListener","Adding listener "+ listener + |
| 1195 | " with filter "+ filter + " and handback "+ handback); |
| 1196 | } |
| 1197 | notifBroadcaster.addNotificationListener(listener, filter, handback); |
| 1198 | } |
| 1199 | |
| 1200 | /** |
| 1201 | * Removes the specified listener from this CommunicatorServer. |
| 1202 | * Note that if the listener has been registered with different |
| 1203 | * handback objects or notification filters, all entries corresponding |
| 1204 | * to the listener will be removed. |
| 1205 | * |
| 1206 | * @param listener The listener object to be removed. |
| 1207 | * |
| 1208 | * @exception ListenerNotFoundException The listener is not registered. |
| 1209 | */ |
| 1210 | public void removeNotificationListener(NotificationListener listener) |
| 1211 | throws ListenerNotFoundException { |
| 1212 | |
| 1213 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINEST)) { |
| 1214 | SNMP_ADAPTOR_LOGGER.logp(Level.FINEST, dbgTag, |
| 1215 | "removeNotificationListener","Removing listener "+ listener); |
| 1216 | } |
| 1217 | notifBroadcaster.removeNotificationListener(listener); |
| 1218 | } |
| 1219 | |
| 1220 | /** |
| 1221 | * Returns an array of MBeanNotificationInfo objects describing |
| 1222 | * the notification types sent by this CommunicatorServer. |
| 1223 | * There is only one type of notifications sent by the CommunicatorServer: |
| 1224 | * it is <tt>{@link javax.management.AttributeChangeNotification}</tt>, |
| 1225 | * sent when the <tt>State</tt> attribute of this CommunicatorServer |
| 1226 | * changes. |
| 1227 | */ |
| 1228 | public MBeanNotificationInfo[] getNotificationInfo() { |
| 1229 | |
| 1230 | // Initialize notifInfos on first call to getNotificationInfo() |
| 1231 | // |
| 1232 | if (notifInfos == null) { |
| 1233 | notifInfos = new MBeanNotificationInfo[1]; |
| 1234 | String[] notifTypes = { |
| 1235 | AttributeChangeNotification.ATTRIBUTE_CHANGE}; |
| 1236 | notifInfos[0] = new MBeanNotificationInfo( notifTypes, |
| 1237 | AttributeChangeNotification.class.getName(), |
| 1238 | "Sent to notify that the value of the State attribute "+ |
| 1239 | "of this CommunicatorServer instance has changed."); |
| 1240 | } |
| 1241 | |
| 1242 | return notifInfos; |
| 1243 | } |
| 1244 | |
| 1245 | /** |
| 1246 | * |
| 1247 | */ |
| 1248 | private void sendStateChangeNotification(int oldState, int newState) { |
| 1249 | |
| 1250 | String oldStateString = getStringForState(oldState); |
| 1251 | String newStateString = getStringForState(newState); |
| 1252 | String message = new StringBuffer().append(dbgTag) |
| 1253 | .append(" The value of attribute State has changed from ") |
| 1254 | .append(oldState).append(" (").append(oldStateString) |
| 1255 | .append(") to ").append(newState).append(" (") |
| 1256 | .append(newStateString).append(").").toString(); |
| 1257 | |
| 1258 | notifCount++; |
| 1259 | AttributeChangeNotification notif = |
| 1260 | new AttributeChangeNotification(this, // source |
| 1261 | notifCount, // sequence number |
| 1262 | System.currentTimeMillis(), // time stamp |
| 1263 | message, // message |
| 1264 | "State", // attribute name |
| 1265 | "int", // attribute type |
| 1266 | new Integer(oldState), // old value |
| 1267 | new Integer(newState) ); // new value |
| 1268 | if (SNMP_ADAPTOR_LOGGER.isLoggable(Level.FINEST)) { |
| 1269 | SNMP_ADAPTOR_LOGGER.logp(Level.FINEST, dbgTag, |
| 1270 | "sendStateChangeNotification","Sending AttributeChangeNotification #" |
| 1271 | + notifCount + " with message: "+ message); |
| 1272 | } |
| 1273 | notifBroadcaster.sendNotification(notif); |
| 1274 | } |
| 1275 | |
| 1276 | /** |
| 1277 | * |
| 1278 | */ |
| 1279 | private static String getStringForState(int s) { |
| 1280 | switch (s) { |
| 1281 | case ONLINE: return "ONLINE"; |
| 1282 | case STARTING: return "STARTING"; |
| 1283 | case OFFLINE: return "OFFLINE"; |
| 1284 | case STOPPING: return "STOPPING"; |
| 1285 | default: return "UNDEFINED"; |
| 1286 | } |
| 1287 | } |
| 1288 | |
| 1289 | |
| 1290 | // |
| 1291 | // MBeanRegistration |
| 1292 | // |
| 1293 | |
| 1294 | /** |
| 1295 | * Preregister method of connector. |
| 1296 | * |
| 1297 | *@param server The <CODE>MBeanServer</CODE> in which the MBean will |
| 1298 | * be registered. |
| 1299 | *@param name The object name of the MBean. |
| 1300 | * |
| 1301 | *@return The name of the MBean registered. |
| 1302 | * |
| 1303 | *@exception java.langException This exception should be caught by |
| 1304 | * the <CODE>MBeanServer</CODE> and re-thrown |
| 1305 | * as an <CODE>MBeanRegistrationException</CODE>. |
| 1306 | */ |
| 1307 | public ObjectName preRegister(MBeanServer server, ObjectName name) |
| 1308 | throws java.lang.Exception { |
| 1309 | objectName = name; |
| 1310 | synchronized (this) { |
| 1311 | if (bottomMBS != null) { |
| 1312 | throw new IllegalArgumentException("connector already " + |
| 1313 | "registered in an MBean " + |
| 1314 | "server"); |
| 1315 | } |
| 1316 | topMBS = bottomMBS = server; |
| 1317 | } |
| 1318 | dbgTag = makeDebugTag(); |
| 1319 | return name; |
| 1320 | } |
| 1321 | |
| 1322 | /** |
| 1323 | * |
| 1324 | *@param registrationDone Indicates whether or not the MBean has been |
| 1325 | * successfully registered in the <CODE>MBeanServer</CODE>. |
| 1326 | * The value false means that the registration phase has failed. |
| 1327 | */ |
| 1328 | public void postRegister(Boolean registrationDone) { |
| 1329 | if (!registrationDone.booleanValue()) { |
| 1330 | synchronized (this) { |
| 1331 | topMBS = bottomMBS = null; |
| 1332 | } |
| 1333 | } |
| 1334 | } |
| 1335 | |
| 1336 | /** |
| 1337 | * Stop the connector. |
| 1338 | * |
| 1339 | * @exception java.langException This exception should be caught by |
| 1340 | * the <CODE>MBeanServer</CODE> and re-thrown |
| 1341 | * as an <CODE>MBeanRegistrationException</CODE>. |
| 1342 | */ |
| 1343 | public void preDeregister() throws java.lang.Exception { |
| 1344 | synchronized (this) { |
| 1345 | topMBS = bottomMBS = null; |
| 1346 | } |
| 1347 | objectName = null ; |
| 1348 | final int cstate = getState(); |
| 1349 | if ((cstate == ONLINE) || ( cstate == STARTING)) { |
| 1350 | stop() ; |
| 1351 | } |
| 1352 | } |
| 1353 | |
| 1354 | /** |
| 1355 | * Do nothing. |
| 1356 | */ |
| 1357 | public void postDeregister(){ |
| 1358 | } |
| 1359 | |
| 1360 | /** |
| 1361 | * Load a class using the default loader repository |
| 1362 | **/ |
| 1363 | Class loadClass(String className) |
| 1364 | throws ClassNotFoundException { |
| 1365 | try { |
| 1366 | return Class.forName(className); |
| 1367 | } catch (ClassNotFoundException e) { |
| 1368 | final ClassLoaderRepository clr = |
| 1369 | MBeanServerFactory.getClassLoaderRepository(bottomMBS); |
| 1370 | if (clr == null) throw new ClassNotFoundException(className); |
| 1371 | return clr.loadClass(className); |
| 1372 | } |
| 1373 | } |
| 1374 | |
| 1375 | } |