Marcel Offermans | a962bc9 | 2009-11-21 17:59:33 +0000 | [diff] [blame^] | 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 | package org.apache.felix.dependencymanager; |
| 20 | |
| 21 | import java.lang.reflect.InvocationTargetException; |
| 22 | import java.lang.reflect.Method; |
| 23 | import java.lang.reflect.Modifier; |
| 24 | import java.lang.reflect.Proxy; |
| 25 | import java.util.AbstractMap; |
| 26 | import java.util.Arrays; |
| 27 | import java.util.Comparator; |
| 28 | import java.util.HashSet; |
| 29 | import java.util.Map; |
| 30 | import java.util.Set; |
| 31 | |
| 32 | import org.osgi.framework.BundleContext; |
| 33 | import org.osgi.framework.Constants; |
| 34 | import org.osgi.framework.InvalidSyntaxException; |
| 35 | import org.osgi.framework.ServiceReference; |
| 36 | |
| 37 | /** |
| 38 | * Service dependency that can track an OSGi service. |
| 39 | * |
| 40 | * @author <a href="mailto:dev@felix.apache.org">Felix Project Team</a> |
| 41 | */ |
| 42 | public class ServiceDependency implements Dependency, ServiceTrackerCustomizer, ServiceComponentDependency { |
| 43 | private boolean m_isRequired; |
| 44 | private Service m_service; |
| 45 | private volatile ServiceTracker m_tracker; |
| 46 | private BundleContext m_context; |
| 47 | private boolean m_isAvailable; |
| 48 | private volatile Class m_trackedServiceName; |
| 49 | private Object m_nullObject; |
| 50 | private volatile String m_trackedServiceFilter; |
| 51 | private volatile String m_trackedServiceFilterUnmodified; |
| 52 | private volatile ServiceReference m_trackedServiceReference; |
| 53 | private volatile boolean m_isStarted; |
| 54 | private Object m_callbackInstance; |
| 55 | private String m_callbackAdded; |
| 56 | private String m_callbackChanged; |
| 57 | private String m_callbackRemoved; |
| 58 | private boolean m_autoConfig; |
| 59 | private ServiceReference m_reference; |
| 60 | private Object m_serviceInstance; |
| 61 | private final Logger m_logger; |
| 62 | private String m_autoConfigInstance; |
| 63 | private boolean m_autoConfigInvoked; |
| 64 | private Object m_defaultImplementation; |
| 65 | private Object m_defaultImplementationInstance; |
| 66 | |
| 67 | private static final Comparator COMPARATOR = new Comparator() { |
| 68 | public int getRank(ServiceReference ref) { |
| 69 | Object ranking = ref.getProperty(Constants.SERVICE_RANKING); |
| 70 | if (ranking != null && (ranking instanceof Integer)) { |
| 71 | return ((Integer) ranking).intValue(); |
| 72 | } |
| 73 | return 0; |
| 74 | } |
| 75 | |
| 76 | public int compare(Object a, Object b) { |
| 77 | ServiceReference ra = (ServiceReference) a, rb = (ServiceReference) b; |
| 78 | int ranka = getRank(ra); |
| 79 | int rankb = getRank(rb); |
| 80 | if (ranka < rankb) { |
| 81 | return -1; |
| 82 | } |
| 83 | else if (ranka > rankb) { |
| 84 | return 1; |
| 85 | } |
| 86 | return 0; |
| 87 | } |
| 88 | }; |
| 89 | |
| 90 | /** |
| 91 | * Entry to wrap service properties behind a Map. |
| 92 | */ |
| 93 | private final static class ServicePropertiesMapEntry implements Map.Entry { |
| 94 | private final String m_key; |
| 95 | private Object m_value; |
| 96 | |
| 97 | public ServicePropertiesMapEntry(String key, Object value) { |
| 98 | m_key = key; |
| 99 | m_value = value; |
| 100 | } |
| 101 | |
| 102 | public Object getKey() { |
| 103 | return m_key; |
| 104 | } |
| 105 | |
| 106 | public Object getValue() { |
| 107 | return m_value; |
| 108 | } |
| 109 | |
| 110 | public String toString() { |
| 111 | return m_key + "=" + m_value; |
| 112 | } |
| 113 | |
| 114 | public Object setValue(Object value) { |
| 115 | Object oldValue = m_value; |
| 116 | m_value = value; |
| 117 | return oldValue; |
| 118 | } |
| 119 | |
| 120 | public boolean equals(Object o) { |
| 121 | if (!(o instanceof Map.Entry)) { |
| 122 | return false; |
| 123 | } |
| 124 | Map.Entry e = (Map.Entry) o; |
| 125 | return eq(m_key, e.getKey()) && eq(m_value, e.getValue()); |
| 126 | } |
| 127 | |
| 128 | public int hashCode() { |
| 129 | return ((m_key == null) ? 0 : m_key.hashCode()) ^ ((m_value == null) ? 0 : m_value.hashCode()); |
| 130 | } |
| 131 | |
| 132 | private static final boolean eq(Object o1, Object o2) { |
| 133 | return (o1 == null ? o2 == null : o1.equals(o2)); |
| 134 | } |
| 135 | } |
| 136 | |
| 137 | /** |
| 138 | * Wraps service properties behind a Map. |
| 139 | */ |
| 140 | private final static class ServicePropertiesMap extends AbstractMap { |
| 141 | private final ServiceReference m_ref; |
| 142 | |
| 143 | public ServicePropertiesMap(ServiceReference ref) { |
| 144 | m_ref = ref; |
| 145 | } |
| 146 | |
| 147 | public Object get(Object key) { |
| 148 | return m_ref.getProperty(key.toString()); |
| 149 | } |
| 150 | |
| 151 | public int size() { |
| 152 | return m_ref.getPropertyKeys().length; |
| 153 | } |
| 154 | |
| 155 | public Set entrySet() { |
| 156 | Set set = new HashSet(); |
| 157 | String[] keys = m_ref.getPropertyKeys(); |
| 158 | for (int i = 0; i < keys.length; i++) { |
| 159 | set.add(new ServicePropertiesMapEntry(keys[i], m_ref.getProperty(keys[i]))); |
| 160 | } |
| 161 | return set; |
| 162 | } |
| 163 | } |
| 164 | |
| 165 | /** |
| 166 | * Creates a new service dependency. |
| 167 | * |
| 168 | * @param context the bundle context |
| 169 | * @param logger the logger |
| 170 | */ |
| 171 | public ServiceDependency(BundleContext context, Logger logger) { |
| 172 | m_context = context; |
| 173 | m_logger = logger; |
| 174 | m_autoConfig = true; |
| 175 | } |
| 176 | |
| 177 | public synchronized boolean isRequired() { |
| 178 | return m_isRequired; |
| 179 | } |
| 180 | |
| 181 | public synchronized boolean isAvailable() { |
| 182 | return m_isAvailable; |
| 183 | } |
| 184 | |
| 185 | public synchronized boolean isAutoConfig() { |
| 186 | return m_autoConfig; |
| 187 | } |
| 188 | |
| 189 | public synchronized Object getService() { |
| 190 | Object service = null; |
| 191 | if (m_isStarted) { |
| 192 | service = m_tracker.getService(); |
| 193 | } |
| 194 | if (service == null) { |
| 195 | service = getDefaultImplementation(); |
| 196 | if (service == null) { |
| 197 | service = getNullObject(); |
| 198 | } |
| 199 | } |
| 200 | return service; |
| 201 | } |
| 202 | |
| 203 | public Object lookupService() { |
| 204 | Object service = null; |
| 205 | if (m_isStarted) { |
| 206 | service = m_tracker.getService(); |
| 207 | } |
| 208 | else { |
| 209 | ServiceReference[] refs = null; |
| 210 | ServiceReference ref = null; |
| 211 | if (m_trackedServiceName != null) { |
| 212 | if (m_trackedServiceFilter != null) { |
| 213 | try { |
| 214 | refs = m_context.getServiceReferences(m_trackedServiceName.getName(), m_trackedServiceFilter); |
| 215 | if (refs != null) { |
| 216 | Arrays.sort(refs, COMPARATOR); |
| 217 | ref = refs[0]; |
| 218 | } |
| 219 | } |
| 220 | catch (InvalidSyntaxException e) { |
| 221 | throw new IllegalStateException("Invalid filter definition for dependency."); |
| 222 | } |
| 223 | } |
| 224 | else if (m_trackedServiceReference != null) { |
| 225 | ref = m_trackedServiceReference; |
| 226 | } |
| 227 | else { |
| 228 | ref = m_context.getServiceReference(m_trackedServiceName.getName()); |
| 229 | } |
| 230 | if (ref != null) { |
| 231 | service = m_context.getService(ref); |
| 232 | } |
| 233 | } |
| 234 | else { |
| 235 | throw new IllegalStateException("Could not lookup dependency, no service name specified."); |
| 236 | } |
| 237 | } |
| 238 | if (service == null) { |
| 239 | service = getDefaultImplementation(); |
| 240 | if (service == null) { |
| 241 | service = getNullObject(); |
| 242 | } |
| 243 | } |
| 244 | return service; |
| 245 | } |
| 246 | |
| 247 | private Object getNullObject() { |
| 248 | if (m_nullObject == null) { |
| 249 | Class trackedServiceName; |
| 250 | synchronized (this) { |
| 251 | trackedServiceName = m_trackedServiceName; |
| 252 | } |
| 253 | try { |
| 254 | m_nullObject = Proxy.newProxyInstance(trackedServiceName.getClassLoader(), new Class[] {trackedServiceName}, new DefaultNullObject()); |
| 255 | } |
| 256 | catch (Exception e) { |
| 257 | m_logger.log(Logger.LOG_ERROR, "Could not create null object for " + trackedServiceName + ".", e); |
| 258 | } |
| 259 | } |
| 260 | return m_nullObject; |
| 261 | } |
| 262 | |
| 263 | private Object getDefaultImplementation() { |
| 264 | if (m_defaultImplementation != null) { |
| 265 | if (m_defaultImplementation instanceof Class) { |
| 266 | try { |
| 267 | m_defaultImplementationInstance = ((Class) m_defaultImplementation).newInstance(); |
| 268 | } |
| 269 | catch (Exception e) { |
| 270 | m_logger.log(Logger.LOG_ERROR, "Could not create default implementation instance of class " + m_defaultImplementation + ".", e); |
| 271 | } |
| 272 | } |
| 273 | else { |
| 274 | m_defaultImplementationInstance = m_defaultImplementation; |
| 275 | } |
| 276 | } |
| 277 | return m_defaultImplementationInstance; |
| 278 | } |
| 279 | |
| 280 | public synchronized Class getInterface() { |
| 281 | return m_trackedServiceName; |
| 282 | } |
| 283 | |
| 284 | public void start(Service service) { |
| 285 | synchronized (this) { |
| 286 | if (m_isStarted) { |
| 287 | throw new IllegalStateException("Service dependency was already started." + m_trackedServiceName); |
| 288 | } |
| 289 | m_service = service; |
| 290 | if (m_trackedServiceName != null) { |
| 291 | if (m_trackedServiceFilter != null) { |
| 292 | try { |
| 293 | m_tracker = new ServiceTracker(m_context, m_context.createFilter(m_trackedServiceFilter), this); |
| 294 | } |
| 295 | catch (InvalidSyntaxException e) { |
| 296 | throw new IllegalStateException("Invalid filter definition for dependency."); |
| 297 | } |
| 298 | } |
| 299 | else if (m_trackedServiceReference != null) { |
| 300 | m_tracker = new ServiceTracker(m_context, m_trackedServiceReference, this); |
| 301 | } |
| 302 | else { |
| 303 | m_tracker = new ServiceTracker(m_context, m_trackedServiceName.getName(), this); |
| 304 | } |
| 305 | } |
| 306 | else { |
| 307 | throw new IllegalStateException("Could not create tracker for dependency, no service name specified."); |
| 308 | } |
| 309 | m_isStarted = true; |
| 310 | } |
| 311 | m_tracker.open(); |
| 312 | } |
| 313 | |
| 314 | public void stop(Service service) { |
| 315 | synchronized (this) { |
| 316 | if (!m_isStarted) { |
| 317 | throw new IllegalStateException("Service dependency was not started."); |
| 318 | } |
| 319 | m_isStarted = false; |
| 320 | } |
| 321 | m_tracker.close(); |
| 322 | m_tracker = null; |
| 323 | } |
| 324 | |
| 325 | public Object addingService(ServiceReference ref) { |
| 326 | Object service = m_context.getService(ref); |
| 327 | // first check to make sure the service is actually an instance of our service |
| 328 | if (!m_trackedServiceName.isInstance(service)) { |
| 329 | return null; |
| 330 | } |
| 331 | |
| 332 | // we remember these for future reference, needed for required service callbacks |
| 333 | m_reference = ref; |
| 334 | m_serviceInstance = service; |
| 335 | return service; |
| 336 | } |
| 337 | |
| 338 | public void addedService(ServiceReference ref, Object service) { |
| 339 | if (makeAvailable()) { |
| 340 | m_service.dependencyAvailable(this); |
| 341 | // try to invoke callback, if specified, but only for optional dependencies |
| 342 | // because callbacks for required dependencies are handled differently |
| 343 | if (!isRequired()) { |
| 344 | invokeAdded(ref, service); |
| 345 | } |
| 346 | } |
| 347 | else { |
| 348 | m_service.dependencyChanged(this); |
| 349 | invokeAdded(ref, service); |
| 350 | } |
| 351 | } |
| 352 | |
| 353 | public void invokeAdded() { |
| 354 | invokeAdded(m_reference, m_serviceInstance); |
| 355 | } |
| 356 | |
| 357 | public void invokeAdded(ServiceReference reference, Object serviceInstance) { |
| 358 | Object[] callbackInstances = getCallbackInstances(); |
| 359 | if ((callbackInstances != null) && (m_callbackAdded != null)) { |
| 360 | invokeCallbackMethod(callbackInstances, m_callbackAdded, reference, serviceInstance); |
| 361 | } |
| 362 | } |
| 363 | |
| 364 | public void modifiedService(ServiceReference ref, Object service) { |
| 365 | m_reference = ref; |
| 366 | m_serviceInstance = service; |
| 367 | m_service.dependencyChanged(this); |
| 368 | // only invoke the changed callback if the service itself is "active" |
| 369 | if (((ServiceImpl) m_service).isRegistered()) { |
| 370 | invokeChanged(ref, service); |
| 371 | } |
| 372 | } |
| 373 | |
| 374 | public void invokeChanged(ServiceReference reference, Object serviceInstance) { |
| 375 | Object[] callbackInstances = getCallbackInstances(); |
| 376 | if ((callbackInstances != null) && (m_callbackChanged != null)) { |
| 377 | invokeCallbackMethod(callbackInstances, m_callbackChanged, reference, serviceInstance); |
| 378 | } |
| 379 | } |
| 380 | |
| 381 | public void removedService(ServiceReference ref, Object service) { |
| 382 | if (makeUnavailable()) { |
| 383 | m_service.dependencyUnavailable(this); |
| 384 | // try to invoke callback, if specified, but only for optional dependencies |
| 385 | // because callbacks for required dependencies are handled differently |
| 386 | if (!isRequired()) { |
| 387 | invokeRemoved(ref, service); |
| 388 | } |
| 389 | } |
| 390 | else { |
| 391 | m_service.dependencyChanged(this); |
| 392 | invokeRemoved(ref, service); |
| 393 | } |
| 394 | |
| 395 | // unget what we got in addingService (see ServiceTracker 701.4.1) |
| 396 | m_context.ungetService(ref); |
| 397 | } |
| 398 | |
| 399 | public void invokeRemoved() { |
| 400 | invokeRemoved(m_reference, m_serviceInstance); |
| 401 | } |
| 402 | |
| 403 | public void invokeRemoved(ServiceReference reference, Object serviceInstance) { |
| 404 | Object[] callbackInstances = getCallbackInstances(); |
| 405 | if ((callbackInstances != null) && (m_callbackRemoved != null)) { |
| 406 | invokeCallbackMethod(callbackInstances, m_callbackRemoved, reference, serviceInstance); |
| 407 | } |
| 408 | } |
| 409 | |
| 410 | private synchronized boolean makeAvailable() { |
| 411 | if (!m_isAvailable) { |
| 412 | m_isAvailable = true; |
| 413 | return true; |
| 414 | } |
| 415 | return false; |
| 416 | } |
| 417 | |
| 418 | private synchronized boolean makeUnavailable() { |
| 419 | if ((m_isAvailable) && (m_tracker.getServiceReference() == null)) { |
| 420 | m_isAvailable = false; |
| 421 | return true; |
| 422 | } |
| 423 | return false; |
| 424 | } |
| 425 | |
| 426 | private synchronized Object[] getCallbackInstances() { |
| 427 | return m_callbackInstance != null ? new Object[] { m_callbackInstance } : ((ServiceImpl) m_service).getCompositionInstances(); |
| 428 | } |
| 429 | |
| 430 | private void invokeCallbackMethod(Object[] instances, String methodName, ServiceReference reference, Object service) { |
| 431 | for (int i = 0; i < instances.length; i++) { |
| 432 | try { |
| 433 | invokeCallbackMethod(instances[i], methodName, reference, service); |
| 434 | } |
| 435 | catch (NoSuchMethodException e) { |
| 436 | m_logger.log(Logger.LOG_DEBUG, "Method '" + methodName + "' does not exist on " + instances[i] + ". Callback skipped."); |
| 437 | } |
| 438 | } |
| 439 | } |
| 440 | |
| 441 | private void invokeCallbackMethod(Object instance, String methodName, ServiceReference reference, Object service) throws NoSuchMethodException { |
| 442 | Class currentClazz = instance.getClass(); |
| 443 | boolean done = false; |
| 444 | while (!done && currentClazz != null) { |
| 445 | Class trackedServiceName; |
| 446 | synchronized (this) { |
| 447 | trackedServiceName = m_trackedServiceName; |
| 448 | } |
| 449 | done = invokeMethod(instance, currentClazz, methodName, |
| 450 | new Class[][] {{ServiceReference.class, trackedServiceName}, {ServiceReference.class, Object.class}, {ServiceReference.class}, {trackedServiceName}, {Object.class}, {}, {Map.class, trackedServiceName}}, |
| 451 | new Object[][] {{reference, service}, {reference, service}, {reference}, {service}, {service}, {}, {new ServicePropertiesMap(reference), service}}, |
| 452 | false); |
| 453 | if (!done) { |
| 454 | currentClazz = currentClazz.getSuperclass(); |
| 455 | } |
| 456 | } |
| 457 | if (!done && currentClazz == null) { |
| 458 | throw new NoSuchMethodException(methodName); |
| 459 | } |
| 460 | } |
| 461 | |
| 462 | private boolean invokeMethod(Object object, Class clazz, String name, Class[][] signatures, Object[][] parameters, boolean isSuper) { |
| 463 | Method m = null; |
| 464 | for (int i = 0; i < signatures.length; i++) { |
| 465 | Class[] signature = signatures[i]; |
| 466 | try { |
| 467 | m = clazz.getDeclaredMethod(name, signature); |
| 468 | if (!(isSuper && Modifier.isPrivate(m.getModifiers()))) { |
| 469 | m.setAccessible(true); |
| 470 | try { |
| 471 | m.invoke(object, parameters[i]); |
| 472 | } |
| 473 | catch (InvocationTargetException e) { |
| 474 | m_logger.log(Logger.LOG_ERROR, "Exception while invoking method " + m + ".", e); |
| 475 | } |
| 476 | // we did find and invoke the method, so we return true |
| 477 | return true; |
| 478 | } |
| 479 | } |
| 480 | catch (NoSuchMethodException e) { |
| 481 | // ignore this and keep looking |
| 482 | } |
| 483 | catch (Exception e) { |
| 484 | // could not even try to invoke the method |
| 485 | m_logger.log(Logger.LOG_ERROR, "Exception while trying to invoke method " + m + ".", e); |
| 486 | } |
| 487 | } |
| 488 | return false; |
| 489 | } |
| 490 | |
| 491 | // ----- CREATION |
| 492 | |
| 493 | /** |
| 494 | * Sets the name of the service that should be tracked. |
| 495 | * |
| 496 | * @param serviceName the name of the service |
| 497 | * @return this service dependency |
| 498 | */ |
| 499 | public synchronized ServiceDependency setService(Class serviceName) { |
| 500 | ensureNotActive(); |
| 501 | if (serviceName == null) { |
| 502 | throw new IllegalArgumentException("Service name cannot be null."); |
| 503 | } |
| 504 | m_trackedServiceName = serviceName; |
| 505 | m_trackedServiceReference = null; |
| 506 | m_trackedServiceFilter = null; |
| 507 | return this; |
| 508 | } |
| 509 | |
| 510 | /** |
| 511 | * Sets the name of the service that should be tracked. You can either specify |
| 512 | * only the name, or the name and a filter. In the latter case, the filter is used |
| 513 | * to track the service and should only return services of the type that was specified |
| 514 | * in the name. To make sure of this, the filter is actually extended internally to |
| 515 | * filter on the correct name. |
| 516 | * |
| 517 | * @param serviceName the name of the service |
| 518 | * @param serviceFilter the filter condition |
| 519 | * @return this service dependency |
| 520 | */ |
| 521 | public synchronized ServiceDependency setService(Class serviceName, String serviceFilter) { |
| 522 | ensureNotActive(); |
| 523 | if (serviceName == null) { |
| 524 | throw new IllegalArgumentException("Service name cannot be null."); |
| 525 | } |
| 526 | m_trackedServiceName = serviceName; |
| 527 | if (serviceFilter != null) { |
| 528 | m_trackedServiceFilterUnmodified = serviceFilter; |
| 529 | m_trackedServiceFilter ="(&(" + Constants.OBJECTCLASS + "=" + serviceName.getName() + ")" + serviceFilter + ")"; |
| 530 | } |
| 531 | else { |
| 532 | m_trackedServiceFilterUnmodified = null; |
| 533 | m_trackedServiceFilter = null; |
| 534 | } |
| 535 | m_trackedServiceReference = null; |
| 536 | return this; |
| 537 | } |
| 538 | |
| 539 | /** |
| 540 | * Sets the name of the service that should be tracked. You can either specify |
| 541 | * only the name, or the name and a reference. In the latter case, the service reference |
| 542 | * is used to track the service and should only return services of the type that was |
| 543 | * specified in the name. |
| 544 | * |
| 545 | * @param serviceName the name of the service |
| 546 | * @param serviceReference the service reference to track |
| 547 | * @return this service dependency |
| 548 | */ |
| 549 | public synchronized ServiceDependency setService(Class serviceName, ServiceReference serviceReference) { |
| 550 | ensureNotActive(); |
| 551 | if (serviceName == null) { |
| 552 | throw new IllegalArgumentException("Service name cannot be null."); |
| 553 | } |
| 554 | m_trackedServiceName = serviceName; |
| 555 | m_trackedServiceReference = serviceReference; |
| 556 | m_trackedServiceFilterUnmodified = null; |
| 557 | m_trackedServiceFilter = null; |
| 558 | return this; |
| 559 | } |
| 560 | |
| 561 | /** |
| 562 | * Sets the default implementation for this service dependency. You can use this to supply |
| 563 | * your own implementation that will be used instead of a Null Object when the dependency is |
| 564 | * not available. This is also convenient if the service dependency is not an interface |
| 565 | * (which would cause the Null Object creation to fail) but a class. |
| 566 | * |
| 567 | * @param implementation the instance to use or the class to instantiate if you want to lazily |
| 568 | * instantiate this implementation |
| 569 | * @return this service dependency |
| 570 | */ |
| 571 | public synchronized ServiceDependency setDefaultImplementation(Object implementation) { |
| 572 | ensureNotActive(); |
| 573 | m_defaultImplementation = implementation; |
| 574 | return this; |
| 575 | } |
| 576 | |
| 577 | /** |
| 578 | * Sets the required flag which determines if this service is required or not. |
| 579 | * |
| 580 | * @param required the required flag |
| 581 | * @return this service dependency |
| 582 | */ |
| 583 | public synchronized ServiceDependency setRequired(boolean required) { |
| 584 | ensureNotActive(); |
| 585 | m_isRequired = required; |
| 586 | return this; |
| 587 | } |
| 588 | |
| 589 | /** |
| 590 | * Sets auto configuration for this service. Auto configuration allows the |
| 591 | * dependency to fill in any attributes in the service implementation that |
| 592 | * are of the same type as this dependency. Default is on. |
| 593 | * |
| 594 | * @param autoConfig the value of auto config |
| 595 | * @return this service dependency |
| 596 | */ |
| 597 | public synchronized ServiceDependency setAutoConfig(boolean autoConfig) { |
| 598 | ensureNotActive(); |
| 599 | m_autoConfig = autoConfig; |
| 600 | m_autoConfigInvoked = true; |
| 601 | return this; |
| 602 | } |
| 603 | |
| 604 | /** |
| 605 | * Sets auto configuration for this service. Auto configuration allows the |
| 606 | * dependency to fill in the attribute in the service implementation that |
| 607 | * has the same type and instance name. |
| 608 | * |
| 609 | * @param instanceName the name of attribute to auto config |
| 610 | * @return this service dependency |
| 611 | */ |
| 612 | public synchronized ServiceDependency setAutoConfig(String instanceName) { |
| 613 | ensureNotActive(); |
| 614 | m_autoConfig = (instanceName != null); |
| 615 | m_autoConfigInstance = instanceName; |
| 616 | m_autoConfigInvoked = true; |
| 617 | return this; |
| 618 | } |
| 619 | |
| 620 | /** |
| 621 | * Sets the callbacks for this service. These callbacks can be used as hooks whenever a |
| 622 | * dependency is added or removed. When you specify callbacks, the auto configuration |
| 623 | * feature is automatically turned off, because we're assuming you don't need it in this |
| 624 | * case. |
| 625 | * |
| 626 | * @param added the method to call when a service was added |
| 627 | * @param removed the method to call when a service was removed |
| 628 | * @return this service dependency |
| 629 | */ |
| 630 | public synchronized ServiceDependency setCallbacks(String added, String removed) { |
| 631 | return setCallbacks(null, added, null, removed); |
| 632 | } |
| 633 | |
| 634 | /** |
| 635 | * Sets the callbacks for this service. These callbacks can be used as hooks whenever a |
| 636 | * dependency is added, changed or removed. When you specify callbacks, the auto |
| 637 | * configuration feature is automatically turned off, because we're assuming you don't |
| 638 | * need it in this case. |
| 639 | * |
| 640 | * @param added the method to call when a service was added |
| 641 | * @param changed the method to call when a service was changed |
| 642 | * @param removed the method to call when a service was removed |
| 643 | * @return this service dependency |
| 644 | */ |
| 645 | public synchronized ServiceDependency setCallbacks(String added, String changed, String removed) { |
| 646 | return setCallbacks(null, added, changed, removed); |
| 647 | } |
| 648 | |
| 649 | /** |
| 650 | * Sets the callbacks for this service. These callbacks can be used as hooks whenever a |
| 651 | * dependency is added or removed. They are called on the instance you provide. When you |
| 652 | * specify callbacks, the auto configuration feature is automatically turned off, because |
| 653 | * we're assuming you don't need it in this case. |
| 654 | * |
| 655 | * @param instance the instance to call the callbacks on |
| 656 | * @param added the method to call when a service was added |
| 657 | * @param removed the method to call when a service was removed |
| 658 | * @return this service dependency |
| 659 | */ |
| 660 | public synchronized ServiceDependency setCallbacks(Object instance, String added, String removed) { |
| 661 | return setCallbacks(instance, added, null, removed); |
| 662 | } |
| 663 | |
| 664 | /** |
| 665 | * Sets the callbacks for this service. These callbacks can be used as hooks whenever a |
| 666 | * dependency is added, changed or removed. They are called on the instance you provide. When you |
| 667 | * specify callbacks, the auto configuration feature is automatically turned off, because |
| 668 | * we're assuming you don't need it in this case. |
| 669 | * |
| 670 | * @param instance the instance to call the callbacks on |
| 671 | * @param added the method to call when a service was added |
| 672 | * @param changed the method to call when a service was changed |
| 673 | * @param removed the method to call when a service was removed |
| 674 | * @return this service dependency |
| 675 | */ |
| 676 | public synchronized ServiceDependency setCallbacks(Object instance, String added, String changed, String removed) { |
| 677 | ensureNotActive(); |
| 678 | // if at least one valid callback is specified, we turn off auto configuration, unless |
| 679 | // someone already explicitly invoked autoConfig |
| 680 | if ((added != null || removed != null || changed != null) && ! m_autoConfigInvoked) { |
| 681 | setAutoConfig(false); |
| 682 | } |
| 683 | m_callbackInstance = instance; |
| 684 | m_callbackAdded = added; |
| 685 | m_callbackChanged = changed; |
| 686 | m_callbackRemoved = removed; |
| 687 | return this; |
| 688 | } |
| 689 | |
| 690 | private void ensureNotActive() { |
| 691 | if (m_tracker != null) { |
| 692 | throw new IllegalStateException("Cannot modify state while active."); |
| 693 | } |
| 694 | } |
| 695 | |
| 696 | public synchronized String toString() { |
| 697 | return "ServiceDependency[" + m_trackedServiceName + " " + m_trackedServiceFilterUnmodified + "]"; |
| 698 | } |
| 699 | |
| 700 | public String getAutoConfigName() { |
| 701 | return m_autoConfigInstance; |
| 702 | } |
| 703 | |
| 704 | public String getName() { |
| 705 | StringBuilder sb = new StringBuilder(); |
| 706 | sb.append(m_trackedServiceName.getName()); |
| 707 | if (m_trackedServiceFilterUnmodified != null) { |
| 708 | sb.append(m_trackedServiceFilterUnmodified); |
| 709 | } |
| 710 | return sb.toString(); |
| 711 | } |
| 712 | |
| 713 | public int getState() { |
| 714 | return (isAvailable() ? 1 : 0) + (isRequired() ? 2 : 0); |
| 715 | } |
| 716 | |
| 717 | public String getType() { |
| 718 | return "service"; |
| 719 | } |
| 720 | } |