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