Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +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 | */ |
Pierre De Rop | e8c339f | 2009-12-04 22:51:51 +0000 | [diff] [blame^] | 19 | package org.apache.felix.dm.impl.dependencies; |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 20 | |
| 21 | import java.lang.reflect.InvocationTargetException; |
| 22 | import java.lang.reflect.Method; |
| 23 | import java.lang.reflect.Modifier; |
Marcel Offermans | 203bdad | 2009-12-04 09:23:04 +0000 | [diff] [blame] | 24 | import java.util.ArrayList; |
| 25 | import java.util.List; |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 26 | import java.util.Properties; |
| 27 | |
Pierre De Rop | e8c339f | 2009-12-04 22:51:51 +0000 | [diff] [blame^] | 28 | import org.apache.felix.dm.dependencies.ResourceDependency; |
| 29 | import org.apache.felix.dm.impl.Logger; |
| 30 | import org.apache.felix.dm.resources.Resource; |
| 31 | import org.apache.felix.dm.resources.ResourceHandler; |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 32 | import org.osgi.framework.BundleContext; |
| 33 | import org.osgi.framework.ServiceRegistration; |
| 34 | |
Pierre De Rop | e8c339f | 2009-12-04 22:51:51 +0000 | [diff] [blame^] | 35 | public class ResourceDependencyImpl implements ResourceDependency, ResourceHandler, DependencyActivation { |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 36 | private volatile BundleContext m_context; |
| 37 | private volatile ServiceRegistration m_registration; |
| 38 | private long m_resourceCounter; |
| 39 | |
| 40 | private Object m_callbackInstance; |
| 41 | private String m_callbackAdded; |
| 42 | private String m_callbackChanged; |
| 43 | private String m_callbackRemoved; |
| 44 | private boolean m_autoConfig; |
| 45 | private final Logger m_logger; |
| 46 | private String m_autoConfigInstance; |
Marcel Offermans | 203bdad | 2009-12-04 09:23:04 +0000 | [diff] [blame] | 47 | // private DependencyService m_service; |
| 48 | protected List m_services = new ArrayList(); |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 49 | private boolean m_isRequired; |
| 50 | private String m_resourceFilter; |
| 51 | private Resource m_resource; |
| 52 | private Resource m_trackedResource; |
Marcel Offermans | 203bdad | 2009-12-04 09:23:04 +0000 | [diff] [blame] | 53 | private boolean m_isStarted; |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 54 | |
| 55 | |
Pierre De Rop | e8c339f | 2009-12-04 22:51:51 +0000 | [diff] [blame^] | 56 | public ResourceDependencyImpl(BundleContext context, Logger logger) { |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 57 | m_context = context; |
| 58 | m_logger = logger; |
| 59 | m_autoConfig = true; |
| 60 | } |
| 61 | |
| 62 | public synchronized boolean isAvailable() { |
| 63 | return m_resourceCounter > 0; |
| 64 | } |
| 65 | |
| 66 | public boolean isRequired() { |
| 67 | return m_isRequired; |
| 68 | } |
| 69 | |
| 70 | public boolean isInstanceBound() { |
| 71 | return false; // TODO for now we are never bound to the service implementation instance |
| 72 | } |
| 73 | |
| 74 | public void start(DependencyService service) { |
Marcel Offermans | 203bdad | 2009-12-04 09:23:04 +0000 | [diff] [blame] | 75 | boolean needsStarting = false; |
| 76 | synchronized (this) { |
| 77 | m_services.add(service); |
| 78 | if (!m_isStarted) { |
| 79 | m_isStarted = true; |
| 80 | needsStarting = true; |
| 81 | } |
| 82 | } |
| 83 | if (needsStarting) { |
| 84 | Properties props = new Properties(); |
| 85 | props.setProperty(Resource.FILTER, m_resourceFilter); |
| 86 | m_registration = m_context.registerService(ResourceHandler.class.getName(), this, props); |
| 87 | } |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 88 | } |
| 89 | |
| 90 | public void stop(DependencyService service) { |
Marcel Offermans | 203bdad | 2009-12-04 09:23:04 +0000 | [diff] [blame] | 91 | boolean needsStopping = false; |
| 92 | synchronized (this) { |
| 93 | if (m_services.size() == 1 && m_services.contains(service)) { |
| 94 | m_isStarted = false; |
| 95 | needsStopping = true; |
| 96 | m_services.remove(service); |
| 97 | } |
| 98 | } |
| 99 | if (needsStopping) { |
| 100 | m_registration.unregister(); |
| 101 | m_registration = null; |
| 102 | } |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 103 | } |
| 104 | |
| 105 | public void added(Resource resource) { |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 106 | long counter; |
Marcel Offermans | 203bdad | 2009-12-04 09:23:04 +0000 | [diff] [blame] | 107 | Object[] services; |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 108 | synchronized (this) { |
| 109 | m_resourceCounter++; |
| 110 | counter = m_resourceCounter; |
| 111 | m_resource = resource; // TODO this really sucks as a way to track a single resource |
Marcel Offermans | 203bdad | 2009-12-04 09:23:04 +0000 | [diff] [blame] | 112 | services = m_services.toArray(); |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 113 | } |
Marcel Offermans | 203bdad | 2009-12-04 09:23:04 +0000 | [diff] [blame] | 114 | for (int i = 0; i < services.length; i++) { |
| 115 | DependencyService ds = (DependencyService) services[i]; |
| 116 | if (counter == 1) { |
| 117 | ds.dependencyAvailable(this); |
| 118 | if (!isRequired()) { |
| 119 | invokeAdded(ds, resource); |
| 120 | } |
| 121 | } |
| 122 | else { |
| 123 | ds.dependencyChanged(this); |
| 124 | invokeAdded(ds, resource); |
| 125 | } |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 126 | } |
| 127 | } |
| 128 | |
| 129 | public void changed(Resource resource) { |
Marcel Offermans | 203bdad | 2009-12-04 09:23:04 +0000 | [diff] [blame] | 130 | Object[] services; |
| 131 | synchronized (this) { |
| 132 | services = m_services.toArray(); |
| 133 | } |
| 134 | for (int i = 0; i < services.length; i++) { |
| 135 | DependencyService ds = (DependencyService) services[i]; |
| 136 | invokeChanged(ds, resource); |
| 137 | } |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 138 | } |
| 139 | |
| 140 | public void removed(Resource resource) { |
| 141 | long counter; |
Marcel Offermans | 203bdad | 2009-12-04 09:23:04 +0000 | [diff] [blame] | 142 | Object[] services; |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 143 | synchronized (this) { |
| 144 | m_resourceCounter--; |
| 145 | counter = m_resourceCounter; |
Marcel Offermans | 203bdad | 2009-12-04 09:23:04 +0000 | [diff] [blame] | 146 | services = m_services.toArray(); |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 147 | } |
Marcel Offermans | 203bdad | 2009-12-04 09:23:04 +0000 | [diff] [blame] | 148 | for (int i = 0; i < services.length; i++) { |
| 149 | DependencyService ds = (DependencyService) services[i]; |
| 150 | if (counter == 0) { |
| 151 | ds.dependencyUnavailable(this); |
| 152 | if (!isRequired()) { |
| 153 | invokeRemoved(ds, resource); |
| 154 | } |
| 155 | } |
| 156 | else { |
| 157 | ds.dependencyChanged(this); |
| 158 | invokeRemoved(ds, resource); |
| 159 | } |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 160 | } |
| 161 | } |
| 162 | |
Marcel Offermans | 203bdad | 2009-12-04 09:23:04 +0000 | [diff] [blame] | 163 | public void invokeAdded(DependencyService ds, Resource serviceInstance) { |
| 164 | Object[] callbackInstances = getCallbackInstances(ds); |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 165 | if ((callbackInstances != null) && (m_callbackAdded != null)) { |
Marcel Offermans | 203bdad | 2009-12-04 09:23:04 +0000 | [diff] [blame] | 166 | invokeCallbackMethod(callbackInstances, m_callbackAdded, serviceInstance); |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 167 | } |
| 168 | } |
| 169 | |
Marcel Offermans | 203bdad | 2009-12-04 09:23:04 +0000 | [diff] [blame] | 170 | public void invokeChanged(DependencyService ds, Resource serviceInstance) { |
| 171 | Object[] callbackInstances = getCallbackInstances(ds); |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 172 | if ((callbackInstances != null) && (m_callbackChanged != null)) { |
Marcel Offermans | 203bdad | 2009-12-04 09:23:04 +0000 | [diff] [blame] | 173 | invokeCallbackMethod(callbackInstances, m_callbackChanged, serviceInstance); |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 174 | } |
| 175 | } |
| 176 | |
Marcel Offermans | 203bdad | 2009-12-04 09:23:04 +0000 | [diff] [blame] | 177 | public void invokeRemoved(DependencyService ds, Resource serviceInstance) { |
| 178 | Object[] callbackInstances = getCallbackInstances(ds); |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 179 | if ((callbackInstances != null) && (m_callbackRemoved != null)) { |
Marcel Offermans | 203bdad | 2009-12-04 09:23:04 +0000 | [diff] [blame] | 180 | invokeCallbackMethod(callbackInstances, m_callbackRemoved, serviceInstance); |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 181 | } |
| 182 | } |
| 183 | |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 184 | /** |
| 185 | * Sets the callbacks for this service. These callbacks can be used as hooks whenever a |
| 186 | * dependency is added or removed. When you specify callbacks, the auto configuration |
| 187 | * feature is automatically turned off, because we're assuming you don't need it in this |
| 188 | * case. |
| 189 | * |
| 190 | * @param added the method to call when a service was added |
| 191 | * @param removed the method to call when a service was removed |
| 192 | * @return this service dependency |
| 193 | */ |
| 194 | public synchronized ResourceDependency setCallbacks(String added, String removed) { |
| 195 | return setCallbacks(null, added, null, removed); |
| 196 | } |
| 197 | |
| 198 | /** |
| 199 | * Sets the callbacks for this service. These callbacks can be used as hooks whenever a |
| 200 | * dependency is added, changed or removed. When you specify callbacks, the auto |
| 201 | * configuration feature is automatically turned off, because we're assuming you don't |
| 202 | * need it in this case. |
| 203 | * |
| 204 | * @param added the method to call when a service was added |
| 205 | * @param changed the method to call when a service was changed |
| 206 | * @param removed the method to call when a service was removed |
| 207 | * @return this service dependency |
| 208 | */ |
| 209 | public synchronized ResourceDependency setCallbacks(String added, String changed, String removed) { |
| 210 | return setCallbacks(null, added, changed, removed); |
| 211 | } |
| 212 | |
| 213 | /** |
| 214 | * Sets the callbacks for this service. These callbacks can be used as hooks whenever a |
| 215 | * dependency is added or removed. They are called on the instance you provide. When you |
| 216 | * specify callbacks, the auto configuration feature is automatically turned off, because |
| 217 | * we're assuming you don't need it in this case. |
| 218 | * |
| 219 | * @param instance the instance to call the callbacks on |
| 220 | * @param added the method to call when a service was added |
| 221 | * @param removed the method to call when a service was removed |
| 222 | * @return this service dependency |
| 223 | */ |
| 224 | public synchronized ResourceDependency setCallbacks(Object instance, String added, String removed) { |
| 225 | return setCallbacks(instance, added, null, removed); |
| 226 | } |
| 227 | |
| 228 | /** |
| 229 | * Sets the callbacks for this service. These callbacks can be used as hooks whenever a |
| 230 | * dependency is added, changed or removed. They are called on the instance you provide. When you |
| 231 | * specify callbacks, the auto configuration feature is automatically turned off, because |
| 232 | * we're assuming you don't need it in this case. |
| 233 | * |
| 234 | * @param instance the instance to call the callbacks on |
| 235 | * @param added the method to call when a service was added |
| 236 | * @param changed the method to call when a service was changed |
| 237 | * @param removed the method to call when a service was removed |
| 238 | * @return this service dependency |
| 239 | */ |
| 240 | public synchronized ResourceDependency setCallbacks(Object instance, String added, String changed, String removed) { |
| 241 | ensureNotActive(); |
| 242 | // if at least one valid callback is specified, we turn off auto configuration |
| 243 | if (added != null || removed != null || changed != null) { |
| 244 | setAutoConfig(false); |
| 245 | } |
| 246 | m_callbackInstance = instance; |
| 247 | m_callbackAdded = added; |
| 248 | m_callbackChanged = changed; |
| 249 | m_callbackRemoved = removed; |
| 250 | return this; |
| 251 | } |
| 252 | |
| 253 | private void ensureNotActive() { |
| 254 | if (m_registration != null) { |
| 255 | throw new IllegalStateException("Cannot modify state while active."); |
| 256 | } |
| 257 | } |
| 258 | |
| 259 | /** |
| 260 | * Sets auto configuration for this service. Auto configuration allows the |
| 261 | * dependency to fill in any attributes in the service implementation that |
| 262 | * are of the same type as this dependency. Default is on. |
| 263 | * |
| 264 | * @param autoConfig the value of auto config |
| 265 | * @return this service dependency |
| 266 | */ |
| 267 | public synchronized ResourceDependency setAutoConfig(boolean autoConfig) { |
| 268 | ensureNotActive(); |
| 269 | m_autoConfig = autoConfig; |
| 270 | return this; |
| 271 | } |
| 272 | |
| 273 | /** |
| 274 | * Sets auto configuration for this service. Auto configuration allows the |
| 275 | * dependency to fill in the attribute in the service implementation that |
| 276 | * has the same type and instance name. |
| 277 | * |
| 278 | * @param instanceName the name of attribute to auto config |
| 279 | * @return this service dependency |
| 280 | */ |
| 281 | public synchronized ResourceDependency setAutoConfig(String instanceName) { |
| 282 | ensureNotActive(); |
| 283 | m_autoConfig = (instanceName != null); |
| 284 | m_autoConfigInstance = instanceName; |
| 285 | return this; |
| 286 | } |
| 287 | |
| 288 | private void invokeCallbackMethod(Object[] instances, String methodName, Object service) { |
| 289 | for (int i = 0; i < instances.length; i++) { |
| 290 | try { |
| 291 | invokeCallbackMethod(instances[i], methodName, service); |
| 292 | } |
| 293 | catch (NoSuchMethodException e) { |
| 294 | m_logger.log(Logger.LOG_DEBUG, "Method '" + methodName + "' does not exist on " + instances[i] + ". Callback skipped."); |
| 295 | } |
| 296 | } |
| 297 | } |
| 298 | |
| 299 | private void invokeCallbackMethod(Object instance, String methodName, Object service) throws NoSuchMethodException { |
| 300 | Class currentClazz = instance.getClass(); |
| 301 | boolean done = false; |
| 302 | while (!done && currentClazz != null) { |
| 303 | done = invokeMethod(instance, currentClazz, methodName, |
| 304 | new Class[][] {{Resource.class}, {Object.class}, {}}, |
| 305 | new Object[][] {{service}, {service}, {}}, |
| 306 | false); |
| 307 | if (!done) { |
| 308 | currentClazz = currentClazz.getSuperclass(); |
| 309 | } |
| 310 | } |
| 311 | if (!done && currentClazz == null) { |
| 312 | throw new NoSuchMethodException(methodName); |
| 313 | } |
| 314 | } |
| 315 | |
| 316 | private boolean invokeMethod(Object object, Class clazz, String name, Class[][] signatures, Object[][] parameters, boolean isSuper) { |
| 317 | Method m = null; |
| 318 | for (int i = 0; i < signatures.length; i++) { |
| 319 | Class[] signature = signatures[i]; |
| 320 | try { |
| 321 | m = clazz.getDeclaredMethod(name, signature); |
| 322 | if (!(isSuper && Modifier.isPrivate(m.getModifiers()))) { |
| 323 | m.setAccessible(true); |
| 324 | try { |
| 325 | m.invoke(object, parameters[i]); |
| 326 | } |
| 327 | catch (InvocationTargetException e) { |
| 328 | m_logger.log(Logger.LOG_ERROR, "Exception while invoking method " + m + ".", e); |
| 329 | } |
| 330 | // we did find and invoke the method, so we return true |
| 331 | return true; |
| 332 | } |
| 333 | } |
| 334 | catch (NoSuchMethodException e) { |
| 335 | // ignore this and keep looking |
| 336 | } |
| 337 | catch (Exception e) { |
| 338 | // could not even try to invoke the method |
| 339 | m_logger.log(Logger.LOG_ERROR, "Exception while trying to invoke method " + m + ".", e); |
| 340 | } |
| 341 | } |
| 342 | return false; |
| 343 | } |
Marcel Offermans | 203bdad | 2009-12-04 09:23:04 +0000 | [diff] [blame] | 344 | |
| 345 | private synchronized Object[] getCallbackInstances(DependencyService ds) { |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 346 | if (m_callbackInstance == null) { |
Marcel Offermans | 203bdad | 2009-12-04 09:23:04 +0000 | [diff] [blame] | 347 | return ds.getCompositionInstances(); |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 348 | } |
Marcel Offermans | 203bdad | 2009-12-04 09:23:04 +0000 | [diff] [blame] | 349 | else { |
| 350 | return new Object[] { m_callbackInstance }; |
| 351 | } |
Marcel Offermans | e14b342 | 2009-11-25 23:04:32 +0000 | [diff] [blame] | 352 | } |
| 353 | |
| 354 | public ResourceDependency setResource(Resource resource) { |
| 355 | m_trackedResource = resource; |
| 356 | return this; |
| 357 | } |
| 358 | |
| 359 | public synchronized ResourceDependency setRequired(boolean required) { |
| 360 | ensureNotActive(); |
| 361 | m_isRequired = required; |
| 362 | return this; |
| 363 | } |
| 364 | |
| 365 | public ResourceDependency setFilter(String resourceFilter) { |
| 366 | m_resourceFilter = resourceFilter; |
| 367 | return this; |
| 368 | } |
| 369 | public synchronized boolean isAutoConfig() { |
| 370 | return m_autoConfig; |
| 371 | } |
| 372 | |
| 373 | public Resource getResource() { |
| 374 | System.out.println("Fetching resource"); |
| 375 | return m_resource; |
| 376 | } |
| 377 | } |