opendaylight/config/config-manager/src/main/java/org/opendaylight/controller/config/manager/impl/ConfigRegistryImpl.java

   1 /*
   2  * Copyright (c) 2013 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.controller.config.manager.impl;
   9
  10 import org.opendaylight.controller.config.api.ConflictingVersionException;
  11 import org.opendaylight.controller.config.api.ModuleIdentifier;
  12 import org.opendaylight.controller.config.api.RuntimeBeanRegistratorAwareModule;
  13 import org.opendaylight.controller.config.api.ServiceReferenceReadableRegistry;
  14 import org.opendaylight.controller.config.api.ServiceReferenceWritableRegistry;
  15 import org.opendaylight.controller.config.api.ValidationException;
  16 import org.opendaylight.controller.config.api.jmx.CommitStatus;
  17 import org.opendaylight.controller.config.api.jmx.ObjectNameUtil;
  18 import org.opendaylight.controller.config.manager.impl.dynamicmbean.DynamicReadableWrapper;
  19 import org.opendaylight.controller.config.manager.impl.factoriesresolver.HierarchicalConfigMBeanFactoriesHolder;
  20 import org.opendaylight.controller.config.manager.impl.factoriesresolver.ModuleFactoriesResolver;
  21 import org.opendaylight.controller.config.manager.impl.jmx.BaseJMXRegistrator;
  22 import org.opendaylight.controller.config.manager.impl.jmx.ModuleJMXRegistrator;
  23 import org.opendaylight.controller.config.manager.impl.jmx.RootRuntimeBeanRegistratorImpl;
  24 import org.opendaylight.controller.config.manager.impl.jmx.TransactionJMXRegistrator;
  25 import org.opendaylight.controller.config.manager.impl.osgi.BeanToOsgiServiceManager;
  26 import org.opendaylight.controller.config.manager.impl.osgi.BeanToOsgiServiceManager.OsgiRegistration;
  27 import org.opendaylight.controller.config.manager.impl.util.LookupBeansUtil;
  28 import org.opendaylight.controller.config.manager.impl.util.ModuleQNameUtil;
  29 import org.opendaylight.controller.config.spi.Module;
  30 import org.opendaylight.controller.config.spi.ModuleFactory;
  31 import org.osgi.framework.BundleContext;
  32 import org.slf4j.Logger;
  33 import org.slf4j.LoggerFactory;
  34
  35 import javax.annotation.concurrent.GuardedBy;
  36 import javax.annotation.concurrent.NotThreadSafe;
  37 import javax.annotation.concurrent.ThreadSafe;
  38 import javax.management.InstanceAlreadyExistsException;
  39 import javax.management.InstanceNotFoundException;
  40 import javax.management.MBeanServer;
  41 import javax.management.MBeanServerFactory;
  42 import javax.management.ObjectName;
  43 import java.util.ArrayList;
  44 import java.util.Collection;
  45 import java.util.Collections;
  46 import java.util.HashMap;
  47 import java.util.Iterator;
  48 import java.util.LinkedList;
  49 import java.util.List;
  50 import java.util.Map;
  51 import java.util.Map.Entry;
  52 import java.util.Set;
  53
  54 /**
  55  * Singleton that is responsible for creating and committing Config
  56  * Transactions. It is registered in Platform MBean Server.
  57  */
  58 @ThreadSafe
  59 public class ConfigRegistryImpl implements AutoCloseable, ConfigRegistryImplMXBean {
  60     private static final Logger logger = LoggerFactory.getLogger(ConfigRegistryImpl.class);
  61
  62     private final ModuleFactoriesResolver resolver;
  63     private final MBeanServer configMBeanServer;
  64
  65     @GuardedBy("this")
  66     private long version = 0;
  67     @GuardedBy("this")
  68     private long versionCounter = 0;
  69
  70     /**
  71      * Contains current configuration in form of {moduleName:{instanceName,read
  72      * only module}} for copying state to new transaction. Each running module
  73      * is present just once, no matter how many interfaces it exposes.
  74      */
  75     @GuardedBy("this")
  76     private final ConfigHolder currentConfig = new ConfigHolder();
  77
  78     /**
  79      * Will return true unless there was a transaction that succeeded during
  80      * validation but failed in second phase of commit. In this case the server
  81      * is unstable and its state is undefined.
  82      */
  83     @GuardedBy("this")
  84     private boolean isHealthy = true;
  85
  86     /**
  87      * Holds Map<transactionName, transactionController> and purges it each time
  88      * its content is requested.
  89      */
  90     @GuardedBy("this")
  91     private final TransactionsHolder transactionsHolder = new TransactionsHolder();
  92
  93     private final BaseJMXRegistrator baseJMXRegistrator;
  94
  95     private final BeanToOsgiServiceManager beanToOsgiServiceManager;
  96
  97     // internal jmx server for read only beans
  98     private final MBeanServer registryMBeanServer;
  99     // internal jmx server shared by all transactions
 100     private final MBeanServer transactionsMBeanServer;
 101
 102     // Used for finding new factory instances for default module functionality
 103     @GuardedBy("this")
 104     private List<ModuleFactory> lastListOfFactories = Collections.emptyList();
 105
 106     @GuardedBy("this") // switched in every 2ndPC
 107     private ServiceReferenceReadableRegistry readableSRRegistry = ServiceReferenceRegistryImpl.createInitialSRLookupRegistry();
 108
 109     // constructor
 110     public ConfigRegistryImpl(ModuleFactoriesResolver resolver,
 111             MBeanServer configMBeanServer) {
 112         this(resolver, configMBeanServer,
 113                 new BaseJMXRegistrator(configMBeanServer));
 114     }
 115
 116     // constructor
 117     public ConfigRegistryImpl(ModuleFactoriesResolver resolver,
 118             MBeanServer configMBeanServer,
 119             BaseJMXRegistrator baseJMXRegistrator) {
 120         this.resolver = resolver;
 121         this.beanToOsgiServiceManager = new BeanToOsgiServiceManager();
 122         this.configMBeanServer = configMBeanServer;
 123         this.baseJMXRegistrator = baseJMXRegistrator;
 124         this.registryMBeanServer = MBeanServerFactory
 125                 .createMBeanServer("ConfigRegistry" + configMBeanServer.getDefaultDomain());
 126         this.transactionsMBeanServer = MBeanServerFactory
 127                 .createMBeanServer("ConfigTransactions" + configMBeanServer.getDefaultDomain());
 128     }
 129
 130     /**
 131      * Create new {@link ConfigTransactionControllerImpl }
 132      */
 133     @Override
 134     public synchronized ObjectName beginConfig() {
 135         return beginConfig(false);
 136     }
 137
 138     /**
 139      * @param blankTransaction true if this transaction is created automatically by
 140      *                         org.opendaylight.controller.config.manager.impl.osgi.BlankTransactionServiceTracker
 141      */
 142     public synchronized ObjectName beginConfig(boolean blankTransaction) {
 143         return beginConfigInternal(blankTransaction).getControllerObjectName();
 144     }
 145
 146     private synchronized ConfigTransactionControllerInternal beginConfigInternal(boolean blankTransaction) {
 147         versionCounter++;
 148         final String transactionName = "ConfigTransaction-" + version + "-" + versionCounter;
 149
 150         TransactionJMXRegistratorFactory factory = new TransactionJMXRegistratorFactory() {
 151             @Override
 152             public TransactionJMXRegistrator create() {
 153                 return baseJMXRegistrator.createTransactionJMXRegistrator(transactionName);
 154             }
 155         };
 156
 157         Map<String, Map.Entry<ModuleFactory, BundleContext>> allCurrentFactories = Collections.unmodifiableMap(
 158                 resolver.getAllFactories());
 159         ConfigTransactionLookupRegistry txLookupRegistry = new ConfigTransactionLookupRegistry(new TransactionIdentifier(
 160                 transactionName), factory, allCurrentFactories);
 161         ServiceReferenceWritableRegistry writableRegistry = ServiceReferenceRegistryImpl.createSRWritableRegistry(
 162                 readableSRRegistry, txLookupRegistry, allCurrentFactories);
 163
 164         ConfigTransactionControllerInternal transactionController = new ConfigTransactionControllerImpl(
 165                 txLookupRegistry, version,
 166                 versionCounter, allCurrentFactories, transactionsMBeanServer,
 167                 configMBeanServer, blankTransaction, writableRegistry);
 168         try {
 169             txLookupRegistry.registerMBean(transactionController, transactionController.getControllerObjectName());
 170         } catch (InstanceAlreadyExistsException e) {
 171             throw new IllegalStateException(e);
 172         }
 173         transactionController.copyExistingModulesAndProcessFactoryDiff(currentConfig.getEntries(), lastListOfFactories);
 174         transactionsHolder.add(transactionName, transactionController);
 175         return transactionController;
 176     }
 177
 178     /**
 179      * {@inheritDoc}
 180      */
 181     @Override
 182     public synchronized CommitStatus commitConfig(ObjectName transactionControllerON)
 183             throws ConflictingVersionException, ValidationException {
 184         final String transactionName = ObjectNameUtil
 185                 .getTransactionName(transactionControllerON);
 186         logger.info("About to commit {}. Current parentVersion: {}, versionCounter {}", transactionName, version, versionCounter);
 187
 188         // find ConfigTransactionController
 189         Map<String, ConfigTransactionControllerInternal> transactions = transactionsHolder.getCurrentTransactions();
 190         ConfigTransactionControllerInternal configTransactionController = transactions.get(transactionName);
 191         if (configTransactionController == null) {
 192             throw new IllegalArgumentException(String.format(
 193                     "Transaction with name '%s' not found", transactionName));
 194         }
 195         // check optimistic lock
 196         if (version != configTransactionController.getParentVersion()) {
 197             throw new ConflictingVersionException(
 198                     String.format(
 199                             "Optimistic lock failed. Expected parent version %d, was %d",
 200                             version,
 201                             configTransactionController.getParentVersion()));
 202         }
 203         // optimistic lock ok
 204
 205         CommitInfo commitInfo = configTransactionController.validateBeforeCommitAndLockTransaction();
 206         lastListOfFactories = Collections.unmodifiableList(configTransactionController.getCurrentlyRegisteredFactories());
 207         // non recoverable from here:
 208         try {
 209             return secondPhaseCommit(
 210                     configTransactionController, commitInfo);
 211         } catch (Throwable t) { // some libs throw Errors: e.g.
 212                                 // javax.xml.ws.spi.FactoryFinder$ConfigurationError
 213             isHealthy = false;
 214             logger.error("Configuration Transaction failed on 2PC, server is unhealthy", t);
 215             if (t instanceof RuntimeException) {
 216                 throw (RuntimeException) t;
 217             } else if (t instanceof Error) {
 218                 throw (Error) t;
 219             } else {
 220                 throw new RuntimeException(t);
 221             }
 222         }
 223     }
 224
 225     private CommitStatus secondPhaseCommit(ConfigTransactionControllerInternal configTransactionController,
 226                                            CommitInfo commitInfo) {
 227
 228         // close instances which were destroyed by the user, including
 229         // (hopefully) runtime beans
 230         for (DestroyedModule toBeDestroyed : commitInfo
 231                 .getDestroyedFromPreviousTransactions()) {
 232             toBeDestroyed.close(); // closes instance (which should close
 233                                    // runtime jmx registrator),
 234             // also closes osgi registration and ModuleJMXRegistrator
 235             // registration
 236             currentConfig.remove(toBeDestroyed.getIdentifier());
 237         }
 238
 239         // set RuntimeBeanRegistrators on beans implementing
 240         // RuntimeBeanRegistratorAwareModule, each module
 241         // should have exactly one runtime jmx registrator.
 242         Map<ModuleIdentifier, RootRuntimeBeanRegistratorImpl> runtimeRegistrators = new HashMap<>();
 243         for (ModuleInternalTransactionalInfo entry : commitInfo.getCommitted()
 244                 .values()) {
 245             RootRuntimeBeanRegistratorImpl runtimeBeanRegistrator;
 246             if (entry.hasOldModule() == false) {
 247                 runtimeBeanRegistrator = baseJMXRegistrator
 248                         .createRuntimeBeanRegistrator(entry.getIdentifier());
 249             } else {
 250                 // reuse old JMX registrator
 251                 runtimeBeanRegistrator = entry.getOldInternalInfo()
 252                         .getRuntimeBeanRegistrator();
 253             }
 254             // set runtime jmx registrator if required
 255             Module module = entry.getModule();
 256             if (module instanceof RuntimeBeanRegistratorAwareModule) {
 257                 ((RuntimeBeanRegistratorAwareModule) module)
 258                         .setRuntimeBeanRegistrator(runtimeBeanRegistrator);
 259             }
 260             // save it to info so it is accessible afterwards
 261             runtimeRegistrators.put(entry.getIdentifier(), runtimeBeanRegistrator);
 262         }
 263
 264         // can register runtime beans
 265         List<ModuleIdentifier> orderedModuleIdentifiers = configTransactionController
 266                 .secondPhaseCommit();
 267
 268         // copy configuration to read only mode
 269         List<ObjectName> newInstances = new LinkedList<>();
 270         List<ObjectName> reusedInstances = new LinkedList<>();
 271         List<ObjectName> recreatedInstances = new LinkedList<>();
 272
 273         Map<Module, ModuleInternalInfo> newConfigEntries = new HashMap<>();
 274
 275         int orderingIdx = 0;
 276         for (ModuleIdentifier moduleIdentifier : orderedModuleIdentifiers) {
 277             ModuleInternalTransactionalInfo entry = commitInfo.getCommitted()
 278                     .get(moduleIdentifier);
 279             if (entry == null)
 280                 throw new NullPointerException("Module not found "
 281                         + moduleIdentifier);
 282             Module module = entry.getModule();
 283             ObjectName primaryReadOnlyON = ObjectNameUtil
 284                     .createReadOnlyModuleON(moduleIdentifier);
 285
 286             // determine if current instance was recreated or reused or is new
 287
 288             // rules for closing resources:
 289             // osgi registration - will be reused if possible.
 290             // module jmx registration - will be (re)created every time, needs
 291             // to be closed here
 292             // runtime jmx registration - should be taken care of by module
 293             // itself
 294             // instance - is closed only if it was destroyed
 295             ModuleJMXRegistrator newModuleJMXRegistrator = baseJMXRegistrator
 296                     .createModuleJMXRegistrator();
 297
 298             OsgiRegistration osgiRegistration = null;
 299             if (entry.hasOldModule()) {
 300                 ModuleInternalInfo oldInternalInfo = entry.getOldInternalInfo();
 301                 DynamicReadableWrapper oldReadableConfigBean = oldInternalInfo
 302                         .getReadableModule();
 303                 currentConfig.remove(entry.getIdentifier());
 304
 305                 // test if old instance == new instance
 306                 if (oldReadableConfigBean.getInstance().equals(module.getInstance())) {
 307                     // reused old instance:
 308                     // wrap in readable dynamic mbean
 309                     reusedInstances.add(primaryReadOnlyON);
 310                     osgiRegistration = oldInternalInfo.getOsgiRegistration();
 311                 } else {
 312                     // recreated instance:
 313                     // it is responsibility of module to call the old instance -
 314                     // we just need to unregister configbean
 315                     recreatedInstances.add(primaryReadOnlyON);
 316
 317                     // close old osgi registration
 318                     oldInternalInfo.getOsgiRegistration().close();
 319                 }
 320
 321                 // close old module jmx registrator
 322                 oldInternalInfo.getModuleJMXRegistrator().close();
 323             } else {
 324                 // new instance:
 325                 // wrap in readable dynamic mbean
 326                 newInstances.add(primaryReadOnlyON);
 327             }
 328
 329             DynamicReadableWrapper newReadableConfigBean = new DynamicReadableWrapper(
 330                     module, module.getInstance(), moduleIdentifier,
 331                     registryMBeanServer, configMBeanServer);
 332
 333             // register to JMX
 334             try {
 335                 newModuleJMXRegistrator.registerMBean(newReadableConfigBean,
 336                         primaryReadOnlyON);
 337             } catch (InstanceAlreadyExistsException e) {
 338                 throw new IllegalStateException(e);
 339             }
 340
 341             // register to OSGi
 342             if (osgiRegistration == null) {
 343                 ModuleFactory moduleFactory = entry.getModuleFactory();
 344                 if(moduleFactory != null) {
 345                     BundleContext bc = configTransactionController.
 346                             getModuleFactoryBundleContext(moduleFactory.getImplementationName());
 347                     osgiRegistration = beanToOsgiServiceManager.registerToOsgi(module.getClass(),
 348                             newReadableConfigBean.getInstance(), entry.getIdentifier(), bc);
 349                 } else {
 350                     throw new NullPointerException(entry.getIdentifier().getFactoryName() + " ModuleFactory not found.");
 351                 }
 352
 353             }
 354
 355             RootRuntimeBeanRegistratorImpl runtimeBeanRegistrator = runtimeRegistrators
 356                     .get(entry.getIdentifier());
 357             ModuleInternalInfo newInfo = new ModuleInternalInfo(
 358                     entry.getIdentifier(), newReadableConfigBean, osgiRegistration,
 359                     runtimeBeanRegistrator, newModuleJMXRegistrator,
 360                     orderingIdx, entry.isDefaultBean());
 361
 362             newConfigEntries.put(module, newInfo);
 363             orderingIdx++;
 364         }
 365         currentConfig.addAll(newConfigEntries.values());
 366
 367         // update version
 368         version = configTransactionController.getVersion();
 369
 370         // switch readable Service Reference Registry
 371         this.readableSRRegistry = ServiceReferenceRegistryImpl.createSRReadableRegistry(configTransactionController.getWritableRegistry(), this);
 372
 373         return new CommitStatus(newInstances, reusedInstances,
 374                 recreatedInstances);
 375     }
 376
 377     /**
 378      * {@inheritDoc}
 379      */
 380     @Override
 381     public synchronized List<ObjectName> getOpenConfigs() {
 382         Map<String, ConfigTransactionControllerInternal> transactions = transactionsHolder
 383                 .getCurrentTransactions();
 384         List<ObjectName> result = new ArrayList<>(transactions.size());
 385         for (ConfigTransactionControllerInternal configTransactionController : transactions
 386                 .values()) {
 387             result.add(configTransactionController.getControllerObjectName());
 388         }
 389         return result;
 390     }
 391
 392     /**
 393      * Abort open transactions and unregister read only modules. Since this
 394      * class is not responsible for registering itself under
 395      * {@link org.opendaylight.controller.config.api.ConfigRegistry#OBJECT_NAME}, it will not unregister itself
 396      * here.
 397      */
 398     @Override
 399     public synchronized void close() {
 400         // abort transactions
 401         Map<String, ConfigTransactionControllerInternal> transactions = transactionsHolder
 402                 .getCurrentTransactions();
 403         for (ConfigTransactionControllerInternal configTransactionController : transactions
 404                 .values()) {
 405             try {
 406                 configTransactionController.abortConfig();
 407             } catch (RuntimeException e) {
 408                 logger.warn("Ignoring exception while aborting {}",
 409                         configTransactionController, e);
 410             }
 411         }
 412
 413         // destroy all live objects one after another in order of the dependency
 414         // hierarchy
 415         List<DestroyedModule> destroyedModules = currentConfig
 416                 .getModulesToBeDestroyed();
 417         for (DestroyedModule destroyedModule : destroyedModules) {
 418             destroyedModule.close();
 419         }
 420         // unregister MBeans that failed to unregister properly
 421         baseJMXRegistrator.close();
 422         // remove jmx servers
 423         MBeanServerFactory.releaseMBeanServer(registryMBeanServer);
 424         MBeanServerFactory.releaseMBeanServer(transactionsMBeanServer);
 425
 426     }
 427
 428     /**
 429      * {@inheritDoc}
 430      */
 431     @Override
 432     public long getVersion() {
 433         return version;
 434     }
 435
 436     /**
 437      * {@inheritDoc}
 438      */
 439     @Override
 440     public Set<String> getAvailableModuleNames() {
 441         return new HierarchicalConfigMBeanFactoriesHolder(
 442                 resolver.getAllFactories()).getModuleNames();
 443     }
 444
 445     /**
 446      * {@inheritDoc}
 447      */
 448     @Override
 449     public boolean isHealthy() {
 450         return isHealthy;
 451     }
 452
 453     // filtering methods
 454
 455     /**
 456      * {@inheritDoc}
 457      */
 458     @Override
 459     public Set<ObjectName> lookupConfigBeans() {
 460         return lookupConfigBeans("*", "*");
 461     }
 462
 463     /**
 464      * {@inheritDoc}
 465      */
 466     @Override
 467     public Set<ObjectName> lookupConfigBeans(String moduleName) {
 468         return lookupConfigBeans(moduleName, "*");
 469     }
 470
 471     /**
 472      * {@inheritDoc}
 473      */
 474     @Override
 475     public ObjectName lookupConfigBean(String moduleName, String instanceName)
 476             throws InstanceNotFoundException {
 477         return LookupBeansUtil.lookupConfigBean(this, moduleName, instanceName);
 478     }
 479
 480     /**
 481      * {@inheritDoc}
 482      */
 483     @Override
 484     public Set<ObjectName> lookupConfigBeans(String moduleName,
 485             String instanceName) {
 486         ObjectName namePattern = ObjectNameUtil.createModulePattern(moduleName,
 487                 instanceName);
 488         return baseJMXRegistrator.queryNames(namePattern, null);
 489     }
 490
 491     /**
 492      * {@inheritDoc}
 493      */
 494     @Override
 495     public Set<ObjectName> lookupRuntimeBeans() {
 496         return lookupRuntimeBeans("*", "*");
 497     }
 498
 499     /**
 500      * {@inheritDoc}
 501      */
 502     @Override
 503     public Set<ObjectName> lookupRuntimeBeans(String moduleName,
 504             String instanceName) {
 505         if (moduleName == null)
 506             moduleName = "*";
 507         if (instanceName == null)
 508             instanceName = "*";
 509         ObjectName namePattern = ObjectNameUtil.createRuntimeBeanPattern(
 510                 moduleName, instanceName);
 511         return baseJMXRegistrator.queryNames(namePattern, null);
 512     }
 513
 514     @Override
 515     public void checkConfigBeanExists(ObjectName objectName) throws InstanceNotFoundException {
 516         ObjectNameUtil.checkDomain(objectName);
 517         ObjectNameUtil.checkType(objectName, ObjectNameUtil.TYPE_MODULE);
 518         String transactionName = ObjectNameUtil.getTransactionName(objectName);
 519         if (transactionName != null) {
 520             throw new IllegalArgumentException("Transaction attribute not supported in registry, wrong ObjectName: " + objectName);
 521         }
 522         // make sure exactly one match is found:
 523         LookupBeansUtil.lookupConfigBean(this, ObjectNameUtil.getFactoryName(objectName), ObjectNameUtil.getInstanceName(objectName));
 524     }
 525
 526     // service reference functionality:
 527     @Override
 528     public synchronized ObjectName lookupConfigBeanByServiceInterfaceName(String serviceInterfaceName, String refName) {
 529         return readableSRRegistry.lookupConfigBeanByServiceInterfaceName(serviceInterfaceName, refName);
 530     }
 531
 532     @Override
 533     public synchronized Map<String, Map<String, ObjectName>> getServiceMapping() {
 534         return readableSRRegistry.getServiceMapping();
 535     }
 536
 537     @Override
 538     public synchronized Map<String, ObjectName> lookupServiceReferencesByServiceInterfaceName(String serviceInterfaceName) {
 539         return readableSRRegistry.lookupServiceReferencesByServiceInterfaceName(serviceInterfaceName);
 540     }
 541
 542     @Override
 543     public synchronized Set<String> lookupServiceInterfaceNames(ObjectName objectName) throws InstanceNotFoundException {
 544         return readableSRRegistry.lookupServiceInterfaceNames(objectName);
 545     }
 546
 547     @Override
 548     public synchronized String getServiceInterfaceName(String namespace, String localName) {
 549         return readableSRRegistry.getServiceInterfaceName(namespace, localName);
 550     }
 551
 552     @Override
 553     public Set<String> getAvailableModuleFactoryQNames() {
 554         return ModuleQNameUtil.getQNames(resolver.getAllFactories());
 555     }
 556
 557 }
 558
 559 /**
 560  * Holds currently running modules
 561  */
 562 @NotThreadSafe
 563 class ConfigHolder {
 564     private final Map<ModuleIdentifier, ModuleInternalInfo> currentConfig = new HashMap<>();
 565
 566     /**
 567      * Add all modules to the internal map. Also add service instance to OSGi
 568      * Service Registry.
 569      */
 570     public void addAll(Collection<ModuleInternalInfo> configInfos) {
 571         if (currentConfig.size() > 0) {
 572             throw new IllegalStateException(
 573                     "Error - some config entries were not removed: "
 574                             + currentConfig);
 575         }
 576         for (ModuleInternalInfo configInfo : configInfos) {
 577             add(configInfo);
 578         }
 579     }
 580
 581     private void add(ModuleInternalInfo configInfo) {
 582         ModuleInternalInfo oldValue = currentConfig.put(configInfo.getName(),
 583                 configInfo);
 584         if (oldValue != null) {
 585             throw new IllegalStateException(
 586                     "Cannot overwrite module with same name:"
 587                             + configInfo.getName() + ":" + configInfo);
 588         }
 589     }
 590
 591     /**
 592      * Remove entry from current config.
 593      */
 594     public void remove(ModuleIdentifier name) {
 595         ModuleInternalInfo removed = currentConfig.remove(name);
 596         if (removed == null) {
 597             throw new IllegalStateException(
 598                     "Cannot remove from ConfigHolder - name not found:" + name);
 599         }
 600     }
 601
 602     public Collection<ModuleInternalInfo> getEntries() {
 603         return currentConfig.values();
 604     }
 605
 606     public List<DestroyedModule> getModulesToBeDestroyed() {
 607         List<DestroyedModule> result = new ArrayList<>();
 608         for (ModuleInternalInfo moduleInternalInfo : getEntries()) {
 609             result.add(moduleInternalInfo.toDestroyedModule());
 610         }
 611         Collections.sort(result);
 612         return result;
 613     }
 614
 615
 616 }
 617
 618 /**
 619  * Holds Map<transactionName, transactionController> and purges it each time its
 620  * content is requested.
 621  */
 622 @NotThreadSafe
 623 class TransactionsHolder {
 624     /**
 625      * This map keeps transaction names and
 626      * {@link ConfigTransactionControllerInternal} instances, because platform
 627      * MBeanServer transforms mbeans into another representation. Map is cleaned
 628      * every time current transactions are requested.
 629      *
 630      */
 631     @GuardedBy("ConfigRegistryImpl.this")
 632     private final Map<String /* transactionName */, ConfigTransactionControllerInternal> transactions = new HashMap<>();
 633
 634     /**
 635      * Can only be called from within synchronized method.
 636      */
 637     public void add(String transactionName,
 638             ConfigTransactionControllerInternal transactionController) {
 639         Object oldValue = transactions.put(transactionName,
 640                 transactionController);
 641         if (oldValue != null) {
 642             throw new IllegalStateException(
 643                     "Error: two transactions with same name");
 644         }
 645     }
 646
 647     /**
 648      * Purges closed transactions from transactions map. Can only be called from
 649      * within synchronized method. Calling this method more than once within the
 650      * method can modify the resulting map that was obtained in previous calls.
 651      *
 652      * @return current view on transactions map.
 653      */
 654     public Map<String, ConfigTransactionControllerInternal> getCurrentTransactions() {
 655         // first, remove closed transaction
 656         for (Iterator<Entry<String, ConfigTransactionControllerInternal>> it = transactions
 657                 .entrySet().iterator(); it.hasNext();) {
 658             Entry<String, ConfigTransactionControllerInternal> entry = it
 659                     .next();
 660             if (entry.getValue().isClosed()) {
 661                 it.remove();
 662             }
 663         }
 664         return Collections.unmodifiableMap(transactions);
 665     }
 666 }