opendaylight/netconf/tools/netconf-testtool/src/main/java/org/opendaylight/controller/netconf/test/tool/NetconfDeviceSimulator.java

   1 /*
   2  * Copyright (c) 2014 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
   9 package org.opendaylight.controller.netconf.test.tool;
  10
  11 import com.google.common.base.Charsets;
  12 import com.google.common.base.Function;
  13 import com.google.common.base.MoreObjects;
  14 import com.google.common.base.Optional;
  15 import com.google.common.collect.Collections2;
  16 import com.google.common.collect.Lists;
  17 import com.google.common.collect.Maps;
  18 import com.google.common.collect.Sets;
  19 import com.google.common.io.CharStreams;
  20 import com.google.common.util.concurrent.CheckedFuture;
  21 import com.google.common.util.concurrent.Futures;
  22 import com.google.common.util.concurrent.ThreadFactoryBuilder;
  23 import io.netty.channel.Channel;
  24 import io.netty.channel.ChannelFuture;
  25 import io.netty.channel.local.LocalAddress;
  26 import io.netty.channel.nio.NioEventLoopGroup;
  27 import io.netty.util.HashedWheelTimer;
  28 import java.io.Closeable;
  29 import java.io.File;
  30 import java.io.IOException;
  31 import java.io.InputStream;
  32 import java.io.InputStreamReader;
  33 import java.net.BindException;
  34 import java.net.Inet4Address;
  35 import java.net.InetSocketAddress;
  36 import java.net.URI;
  37 import java.net.UnknownHostException;
  38 import java.nio.file.Files;
  39 import java.nio.file.Path;
  40 import java.util.AbstractMap;
  41 import java.util.Collections;
  42 import java.util.Date;
  43 import java.util.HashMap;
  44 import java.util.List;
  45 import java.util.Map;
  46 import java.util.NavigableMap;
  47 import java.util.Set;
  48 import java.util.concurrent.ExecutionException;
  49 import java.util.concurrent.ExecutorService;
  50 import java.util.concurrent.Executors;
  51 import java.util.concurrent.ScheduledExecutorService;
  52 import org.antlr.v4.runtime.ParserRuleContext;
  53 import org.antlr.v4.runtime.tree.ParseTreeWalker;
  54 import org.apache.sshd.common.util.ThreadUtils;
  55 import org.apache.sshd.server.PasswordAuthenticator;
  56 import org.apache.sshd.server.keyprovider.PEMGeneratorHostKeyProvider;
  57 import org.apache.sshd.server.session.ServerSession;
  58 import org.opendaylight.controller.config.util.capability.Capability;
  59 import org.opendaylight.controller.netconf.api.monitoring.CapabilityListener;
  60 import org.opendaylight.controller.netconf.api.monitoring.NetconfMonitoringService;
  61 import org.opendaylight.controller.netconf.api.xml.XmlNetconfConstants;
  62 import org.opendaylight.controller.netconf.impl.NetconfServerDispatcherImpl;
  63 import org.opendaylight.controller.netconf.impl.NetconfServerSessionNegotiatorFactory;
  64 import org.opendaylight.controller.netconf.impl.SessionIdProvider;
  65 import org.opendaylight.controller.netconf.impl.osgi.AggregatedNetconfOperationServiceFactory;
  66 import org.opendaylight.controller.netconf.mapping.api.NetconfOperation;
  67 import org.opendaylight.controller.netconf.mapping.api.NetconfOperationService;
  68 import org.opendaylight.controller.netconf.mapping.api.NetconfOperationServiceFactory;
  69 import org.opendaylight.controller.netconf.monitoring.osgi.NetconfMonitoringActivator;
  70 import org.opendaylight.controller.netconf.monitoring.osgi.NetconfMonitoringOperationService;
  71 import org.opendaylight.controller.netconf.ssh.SshProxyServer;
  72 import org.opendaylight.controller.netconf.ssh.SshProxyServerConfiguration;
  73 import org.opendaylight.controller.netconf.ssh.SshProxyServerConfigurationBuilder;
  74 import org.opendaylight.controller.netconf.test.tool.rpc.DataList;
  75 import org.opendaylight.controller.netconf.test.tool.rpc.SimulatedCommit;
  76 import org.opendaylight.controller.netconf.test.tool.rpc.SimulatedCreateSubscription;
  77 import org.opendaylight.controller.netconf.test.tool.rpc.SimulatedEditConfig;
  78 import org.opendaylight.controller.netconf.test.tool.rpc.SimulatedGet;
  79 import org.opendaylight.controller.netconf.test.tool.rpc.SimulatedGetConfig;
  80 import org.opendaylight.controller.netconf.test.tool.rpc.SimulatedLock;
  81 import org.opendaylight.controller.netconf.test.tool.rpc.SimulatedUnLock;
  82 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  83 import org.opendaylight.yangtools.yang.model.repo.api.SchemaSourceException;
  84 import org.opendaylight.yangtools.yang.model.repo.api.SchemaSourceRepresentation;
  85 import org.opendaylight.yangtools.yang.model.repo.api.SourceIdentifier;
  86 import org.opendaylight.yangtools.yang.model.repo.api.YangTextSchemaSource;
  87 import org.opendaylight.yangtools.yang.model.repo.spi.PotentialSchemaSource;
  88 import org.opendaylight.yangtools.yang.model.repo.spi.SchemaSourceListener;
  89 import org.opendaylight.yangtools.yang.model.repo.spi.SchemaSourceProvider;
  90 import org.opendaylight.yangtools.yang.model.repo.util.FilesystemSchemaSourceCache;
  91 import org.opendaylight.yangtools.yang.parser.builder.impl.BuilderUtils;
  92 import org.opendaylight.yangtools.yang.parser.builder.impl.ModuleBuilder;
  93 import org.opendaylight.yangtools.yang.parser.impl.YangParserListenerImpl;
  94 import org.opendaylight.yangtools.yang.parser.repo.SharedSchemaRepository;
  95 import org.opendaylight.yangtools.yang.parser.util.ASTSchemaSource;
  96 import org.opendaylight.yangtools.yang.parser.util.TextToASTTransformer;
  97 import org.slf4j.Logger;
  98 import org.slf4j.LoggerFactory;
  99
 100 public class NetconfDeviceSimulator implements Closeable {
 101
 102     private static final Logger LOG = LoggerFactory.getLogger(NetconfDeviceSimulator.class);
 103
 104     private final NioEventLoopGroup nettyThreadgroup;
 105     private final HashedWheelTimer hashedWheelTimer;
 106     private final List<Channel> devicesChannels = Lists.newArrayList();
 107     private final List<SshProxyServer> sshWrappers = Lists.newArrayList();
 108     private final ScheduledExecutorService minaTimerExecutor;
 109     private final ExecutorService nioExecutor;
 110
 111     private boolean sendFakeSchema = false;
 112
 113     public NetconfDeviceSimulator() {
 114         // TODO make pool size configurable
 115         this(new NioEventLoopGroup(), new HashedWheelTimer(),
 116                 Executors.newScheduledThreadPool(8, new ThreadFactoryBuilder().setNameFormat("netconf-ssh-server-mina-timers-%d").build()),
 117                 ThreadUtils.newFixedThreadPool("netconf-ssh-server-nio-group", 8));
 118     }
 119
 120     private NetconfDeviceSimulator(final NioEventLoopGroup eventExecutors, final HashedWheelTimer hashedWheelTimer, final ScheduledExecutorService minaTimerExecutor, final ExecutorService nioExecutor) {
 121         this.nettyThreadgroup = eventExecutors;
 122         this.hashedWheelTimer = hashedWheelTimer;
 123         this.minaTimerExecutor = minaTimerExecutor;
 124         this.nioExecutor = nioExecutor;
 125     }
 126
 127     private NetconfServerDispatcherImpl createDispatcher(final Map<ModuleBuilder, String> moduleBuilders, final boolean exi, final int generateConfigsTimeout, final Optional<File> notificationsFile) {
 128
 129         final Set<Capability> capabilities = Sets.newHashSet(Collections2.transform(moduleBuilders.keySet(), new Function<ModuleBuilder, Capability>() {
 130             @Override
 131             public Capability apply(final ModuleBuilder input) {
 132                 if (sendFakeSchema) {
 133                     sendFakeSchema = false;
 134                     return new FakeModuleBuilderCapability(input, moduleBuilders.get(input));
 135                 } else {
 136                     return new ModuleBuilderCapability(input, moduleBuilders.get(input));
 137                 }
 138             }
 139         }));
 140
 141         final SessionIdProvider idProvider = new SessionIdProvider();
 142
 143         final AggregatedNetconfOperationServiceFactory aggregatedNetconfOperationServiceFactory = new AggregatedNetconfOperationServiceFactory();
 144         final SimulatedOperationProvider simulatedOperationProvider = new SimulatedOperationProvider(idProvider, capabilities, notificationsFile);
 145
 146         final NetconfMonitoringService monitoringService1 = new DummyMonitoringService(capabilities);
 147
 148         final NetconfMonitoringActivator.NetconfMonitoringOperationServiceFactory monitoringService =
 149                 new NetconfMonitoringActivator.NetconfMonitoringOperationServiceFactory(
 150                         new NetconfMonitoringOperationService(monitoringService1));
 151         aggregatedNetconfOperationServiceFactory.onAddNetconfOperationServiceFactory(simulatedOperationProvider);
 152         aggregatedNetconfOperationServiceFactory.onAddNetconfOperationServiceFactory(monitoringService);
 153
 154         final Set<String> serverCapabilities = exi
 155                 ? NetconfServerSessionNegotiatorFactory.DEFAULT_BASE_CAPABILITIES
 156                 : Sets.newHashSet(XmlNetconfConstants.URN_IETF_PARAMS_NETCONF_BASE_1_0, XmlNetconfConstants.URN_IETF_PARAMS_NETCONF_BASE_1_1);
 157
 158         final NetconfServerSessionNegotiatorFactory serverNegotiatorFactory = new NetconfServerSessionNegotiatorFactory(
 159                 hashedWheelTimer, aggregatedNetconfOperationServiceFactory, idProvider, generateConfigsTimeout, monitoringService1, serverCapabilities);
 160
 161         final NetconfServerDispatcherImpl.ServerChannelInitializer serverChannelInitializer = new NetconfServerDispatcherImpl.ServerChannelInitializer(
 162                 serverNegotiatorFactory);
 163         return new NetconfServerDispatcherImpl(serverChannelInitializer, nettyThreadgroup, nettyThreadgroup);
 164     }
 165
 166     private Map<ModuleBuilder, String> toModuleBuilders(final Map<SourceIdentifier, Map.Entry<ASTSchemaSource, YangTextSchemaSource>> sources) {
 167         final Map<SourceIdentifier, ParserRuleContext> asts = Maps.transformValues(sources, new Function<Map.Entry<ASTSchemaSource, YangTextSchemaSource>, ParserRuleContext>() {
 168             @Override
 169             public ParserRuleContext apply(final Map.Entry<ASTSchemaSource, YangTextSchemaSource> input) {
 170                 return input.getKey().getAST();
 171             }
 172         });
 173         final Map<String, NavigableMap<Date, URI>> namespaceContext = BuilderUtils.createYangNamespaceContext(
 174                 asts.values(), Optional.<SchemaContext>absent());
 175
 176         final ParseTreeWalker walker = new ParseTreeWalker();
 177         final Map<ModuleBuilder, String> sourceToBuilder = new HashMap<>();
 178
 179         for (final Map.Entry<SourceIdentifier, ParserRuleContext> entry : asts.entrySet()) {
 180             final ModuleBuilder moduleBuilder = YangParserListenerImpl.create(namespaceContext, entry.getKey().getName(),
 181                     walker, entry.getValue()).getModuleBuilder();
 182
 183             try(InputStreamReader stream = new InputStreamReader(sources.get(entry.getKey()).getValue().openStream(), Charsets.UTF_8)) {
 184                 sourceToBuilder.put(moduleBuilder, CharStreams.toString(stream));
 185             } catch (final IOException e) {
 186                 throw new RuntimeException(e);
 187             }
 188         }
 189
 190         return sourceToBuilder;
 191     }
 192
 193
 194     public List<Integer> start(final Main.Params params) {
 195         LOG.info("Starting {}, {} simulated devices starting on port {}", params.deviceCount, params.ssh ? "SSH" : "TCP", params.startingPort);
 196
 197         final Map<ModuleBuilder, String> moduleBuilders = parseSchemasToModuleBuilders(params);
 198
 199         final NetconfServerDispatcherImpl dispatcher = createDispatcher(moduleBuilders, params.exi, params.generateConfigsTimeout, Optional.fromNullable(params.notificationFile));
 200
 201         int currentPort = params.startingPort;
 202
 203         final List<Integer> openDevices = Lists.newArrayList();
 204
 205         // Generate key to temp folder
 206         final PEMGeneratorHostKeyProvider keyPairProvider = getPemGeneratorHostKeyProvider();
 207
 208         for (int i = 0; i < params.deviceCount; i++) {
 209             if (currentPort > 65535) {
 210                 LOG.warn("Port cannot be greater than 65535, stopping further attempts.");
 211                 break;
 212             }
 213             final InetSocketAddress address = getAddress(currentPort);
 214
 215             final ChannelFuture server;
 216             if(params.ssh) {
 217                 final InetSocketAddress bindingAddress = InetSocketAddress.createUnresolved("0.0.0.0", currentPort);
 218                 final LocalAddress tcpLocalAddress = new LocalAddress(address.toString());
 219
 220                 server = dispatcher.createLocalServer(tcpLocalAddress);
 221                 try {
 222                     final SshProxyServer sshServer = new SshProxyServer(minaTimerExecutor, nettyThreadgroup, nioExecutor);
 223                     sshServer.bind(getSshConfiguration(bindingAddress, tcpLocalAddress, keyPairProvider));
 224                     sshWrappers.add(sshServer);
 225                 } catch (final BindException e) {
 226                     LOG.warn("Cannot start simulated device on {}, port already in use. Skipping.", address);
 227                     // Close local server and continue
 228                     server.cancel(true);
 229                     if(server.isDone()) {
 230                         server.channel().close();
 231                     }
 232                     continue;
 233                 } catch (final IOException e) {
 234                     LOG.warn("Cannot start simulated device on {} due to IOException.", address, e);
 235                     break;
 236                 } finally {
 237                     currentPort++;
 238                 }
 239
 240                 try {
 241                     server.get();
 242                 } catch (final InterruptedException e) {
 243                     throw new RuntimeException(e);
 244                 } catch (final ExecutionException e) {
 245                     LOG.warn("Cannot start ssh simulated device on {}, skipping", address, e);
 246                     continue;
 247                 }
 248
 249                 LOG.debug("Simulated SSH device started on {}", address);
 250
 251             } else {
 252                 server = dispatcher.createServer(address);
 253                 currentPort++;
 254
 255                 try {
 256                     server.get();
 257                 } catch (final InterruptedException e) {
 258                     throw new RuntimeException(e);
 259                 } catch (final ExecutionException e) {
 260                     LOG.warn("Cannot start tcp simulated device on {}, skipping", address, e);
 261                     continue;
 262                 }
 263
 264                 LOG.debug("Simulated TCP device started on {}", address);
 265             }
 266
 267             devicesChannels.add(server.channel());
 268             openDevices.add(currentPort - 1);
 269         }
 270
 271         if(openDevices.size() == params.deviceCount) {
 272             LOG.info("All simulated devices started successfully from port {} to {}", params.startingPort, currentPort - 1);
 273         } else if (openDevices.size() == 0) {
 274             LOG.warn("No simulated devices started.");
 275         } else {
 276             LOG.warn("Not all simulated devices started successfully. Started devices ar on ports {}", openDevices);
 277         }
 278
 279         return openDevices;
 280     }
 281
 282     private SshProxyServerConfiguration getSshConfiguration(final InetSocketAddress bindingAddress, final LocalAddress tcpLocalAddress, final PEMGeneratorHostKeyProvider keyPairProvider) throws IOException {
 283         return new SshProxyServerConfigurationBuilder()
 284                 .setBindingAddress(bindingAddress)
 285                 .setLocalAddress(tcpLocalAddress)
 286                 .setAuthenticator(new PasswordAuthenticator() {
 287                     @Override
 288                     public boolean authenticate(final String username, final String password, final ServerSession session) {
 289                         return true;
 290                     }
 291                 })
 292                 .setKeyPairProvider(keyPairProvider)
 293                 .setIdleTimeout(Integer.MAX_VALUE)
 294                 .createSshProxyServerConfiguration();
 295     }
 296
 297     private PEMGeneratorHostKeyProvider getPemGeneratorHostKeyProvider() {
 298         try {
 299             final Path tempFile = Files.createTempFile("tempKeyNetconfTest", "suffix");
 300             return new PEMGeneratorHostKeyProvider(tempFile.toAbsolutePath().toString());
 301         } catch (final IOException e) {
 302             LOG.error("Unable to generate PEM key", e);
 303             throw new RuntimeException(e);
 304         }
 305     }
 306
 307     private Map<ModuleBuilder, String> parseSchemasToModuleBuilders(final Main.Params params) {
 308         final SharedSchemaRepository consumer = new SharedSchemaRepository("netconf-simulator");
 309         consumer.registerSchemaSourceListener(TextToASTTransformer.create(consumer, consumer));
 310
 311         final Set<SourceIdentifier> loadedSources = Sets.newHashSet();
 312
 313         consumer.registerSchemaSourceListener(new SchemaSourceListener() {
 314             @Override
 315             public void schemaSourceEncountered(final SchemaSourceRepresentation schemaSourceRepresentation) {}
 316
 317             @Override
 318             public void schemaSourceRegistered(final Iterable<PotentialSchemaSource<?>> potentialSchemaSources) {
 319                 for (final PotentialSchemaSource<?> potentialSchemaSource : potentialSchemaSources) {
 320                     loadedSources.add(potentialSchemaSource.getSourceIdentifier());
 321                 }
 322             }
 323
 324             @Override
 325             public void schemaSourceUnregistered(final PotentialSchemaSource<?> potentialSchemaSource) {}
 326         });
 327
 328         if(params.schemasDir != null) {
 329             final FilesystemSchemaSourceCache<YangTextSchemaSource> cache = new FilesystemSchemaSourceCache<>(consumer, YangTextSchemaSource.class, params.schemasDir);
 330             consumer.registerSchemaSourceListener(cache);
 331         }
 332
 333         addDefaultSchemas(consumer);
 334
 335         final Map<SourceIdentifier, Map.Entry<ASTSchemaSource, YangTextSchemaSource>> asts = Maps.newHashMap();
 336         for (final SourceIdentifier loadedSource : loadedSources) {
 337             try {
 338                 final CheckedFuture<ASTSchemaSource, SchemaSourceException> ast = consumer.getSchemaSource(loadedSource, ASTSchemaSource.class);
 339                 final CheckedFuture<YangTextSchemaSource, SchemaSourceException> text = consumer.getSchemaSource(loadedSource, YangTextSchemaSource.class);
 340                 asts.put(loadedSource, new AbstractMap.SimpleEntry<>(ast.get(), text.get()));
 341             } catch (final InterruptedException e) {
 342                 throw new RuntimeException(e);
 343             } catch (final ExecutionException e) {
 344                 throw new RuntimeException("Cannot parse schema context", e);
 345             }
 346         }
 347         return toModuleBuilders(asts);
 348     }
 349
 350     private void addDefaultSchemas(final SharedSchemaRepository consumer) {
 351         SourceIdentifier sId = new SourceIdentifier("ietf-netconf-monitoring", "2010-10-04");
 352         registerSource(consumer, "/META-INF/yang/ietf-netconf-monitoring.yang", sId);
 353
 354         sId = new SourceIdentifier("ietf-netconf-monitoring-extension", "2013-12-10");
 355         registerSource(consumer, "/META-INF/yang/ietf-netconf-monitoring-extension.yang", sId);
 356
 357         sId = new SourceIdentifier("ietf-yang-types", "2010-09-24");
 358         registerSource(consumer, "/META-INF/yang/ietf-yang-types.yang", sId);
 359
 360         sId = new SourceIdentifier("ietf-inet-types", "2010-09-24");
 361         registerSource(consumer, "/META-INF/yang/ietf-inet-types.yang", sId);
 362     }
 363
 364     private void registerSource(final SharedSchemaRepository consumer, final String resource, final SourceIdentifier sourceId) {
 365         consumer.registerSchemaSource(new SchemaSourceProvider<SchemaSourceRepresentation>() {
 366             @Override
 367             public CheckedFuture<? extends SchemaSourceRepresentation, SchemaSourceException> getSource(final SourceIdentifier sourceIdentifier) {
 368                 return Futures.immediateCheckedFuture(new YangTextSchemaSource(sourceId) {
 369                     @Override
 370                     protected MoreObjects.ToStringHelper addToStringAttributes(final MoreObjects.ToStringHelper toStringHelper) {
 371                         return toStringHelper;
 372                     }
 373
 374                     @Override
 375                     public InputStream openStream() throws IOException {
 376                         return getClass().getResourceAsStream(resource);
 377                     }
 378                 });
 379             }
 380         }, PotentialSchemaSource.create(sourceId, YangTextSchemaSource.class, PotentialSchemaSource.Costs.IMMEDIATE.getValue()));
 381     }
 382
 383     private static InetSocketAddress getAddress(final int port) {
 384         try {
 385             // TODO make address configurable
 386             return new InetSocketAddress(Inet4Address.getByName("0.0.0.0"), port);
 387         } catch (final UnknownHostException e) {
 388             throw new RuntimeException(e);
 389         }
 390     }
 391
 392     @Override
 393     public void close() {
 394         for (final SshProxyServer sshWrapper : sshWrappers) {
 395             sshWrapper.close();
 396         }
 397         for (final Channel deviceCh : devicesChannels) {
 398             deviceCh.close();
 399         }
 400         nettyThreadgroup.shutdownGracefully();
 401         minaTimerExecutor.shutdownNow();
 402         nioExecutor.shutdownNow();
 403         // close Everything
 404     }
 405
 406     private static class SimulatedOperationProvider implements NetconfOperationServiceFactory {
 407         private final Set<Capability> caps;
 408         private final SimulatedOperationService simulatedOperationService;
 409
 410
 411         public SimulatedOperationProvider(final SessionIdProvider idProvider, final Set<Capability> caps, final Optional<File> notificationsFile) {
 412             this.caps = caps;
 413             simulatedOperationService = new SimulatedOperationService(idProvider.getCurrentSessionId(), notificationsFile);
 414         }
 415
 416         @Override
 417         public Set<Capability> getCapabilities() {
 418             return caps;
 419         }
 420
 421         @Override
 422         public AutoCloseable registerCapabilityListener(final CapabilityListener listener) {
 423             listener.onCapabilitiesChanged(caps, Collections.<Capability>emptySet());
 424             return new AutoCloseable() {
 425                 @Override
 426                 public void close() throws Exception {}
 427             };
 428         }
 429
 430         @Override
 431         public NetconfOperationService createService(final String netconfSessionIdForReporting) {
 432             return simulatedOperationService;
 433         }
 434
 435         static class SimulatedOperationService implements NetconfOperationService {
 436             private final long currentSessionId;
 437             private final Optional<File> notificationsFile;
 438
 439             public SimulatedOperationService(final long currentSessionId, final Optional<File> notificationsFile) {
 440                 this.currentSessionId = currentSessionId;
 441                 this.notificationsFile = notificationsFile;
 442             }
 443
 444             @Override
 445             public Set<NetconfOperation> getNetconfOperations() {
 446                 final DataList storage = new DataList();
 447                 final SimulatedGet sGet = new SimulatedGet(String.valueOf(currentSessionId), storage);
 448                 final SimulatedEditConfig sEditConfig = new SimulatedEditConfig(String.valueOf(currentSessionId), storage);
 449                 final SimulatedGetConfig sGetConfig = new SimulatedGetConfig(String.valueOf(currentSessionId), storage);
 450                 final SimulatedCommit sCommit = new SimulatedCommit(String.valueOf(currentSessionId));
 451                 final SimulatedLock sLock = new SimulatedLock(String.valueOf(currentSessionId));
 452                 final SimulatedUnLock sUnlock = new SimulatedUnLock(String.valueOf(currentSessionId));
 453                 final SimulatedCreateSubscription sCreateSubs = new SimulatedCreateSubscription(String.valueOf(currentSessionId), notificationsFile);
 454                 return Sets.<NetconfOperation>newHashSet(sGet,  sGetConfig, sEditConfig, sCommit, sLock, sUnlock, sCreateSubs);
 455             }
 456
 457             @Override
 458             public void close() {
 459             }
 460
 461         }
 462     }
 463
 464 }