X-Git-Url: https://git.opendaylight.org/gerrit/gitweb?p=controller.git;a=blobdiff_plain;f=opendaylight%2Fmd-sal%2Fsamples%2Ftoaster-provider%2Fsrc%2Fmain%2Fjava%2Forg%2Fopendaylight%2Fcontroller%2Fsample%2Ftoaster%2Fprovider%2FOpendaylightToaster.java;h=0fcd474d9c0e631185a37e28836f40b8e66dd822;hp=2ecd7e7b684fe8bdafd6af17527cbb21daeee83f;hb=05522e0190cec637f190ceb5aedf785039f08e57;hpb=b80124e3f7b11cf2f5e5bd4a6b033d855ff4d0d4 diff --git a/opendaylight/md-sal/samples/toaster-provider/src/main/java/org/opendaylight/controller/sample/toaster/provider/OpendaylightToaster.java b/opendaylight/md-sal/samples/toaster-provider/src/main/java/org/opendaylight/controller/sample/toaster/provider/OpendaylightToaster.java index 2ecd7e7b68..0fcd474d9c 100644 --- a/opendaylight/md-sal/samples/toaster-provider/src/main/java/org/opendaylight/controller/sample/toaster/provider/OpendaylightToaster.java +++ b/opendaylight/md-sal/samples/toaster-provider/src/main/java/org/opendaylight/controller/sample/toaster/provider/OpendaylightToaster.java @@ -7,182 +7,312 @@ */ package org.opendaylight.controller.sample.toaster.provider; -import java.util.Arrays; -import java.util.Collections; +import static org.opendaylight.mdsal.binding.api.DataObjectModification.ModificationType.DELETE; +import static org.opendaylight.mdsal.binding.api.DataObjectModification.ModificationType.WRITE; +import static org.opendaylight.mdsal.common.api.LogicalDatastoreType.CONFIGURATION; +import static org.opendaylight.mdsal.common.api.LogicalDatastoreType.OPERATIONAL; +import static org.opendaylight.yangtools.yang.common.RpcError.ErrorType.APPLICATION; + +import com.google.common.base.Function; +import com.google.common.base.Preconditions; +import com.google.common.util.concurrent.FluentFuture; +import com.google.common.util.concurrent.FutureCallback; +import com.google.common.util.concurrent.Futures; +import com.google.common.util.concurrent.ListenableFuture; +import com.google.common.util.concurrent.MoreExecutors; +import com.google.common.util.concurrent.SettableFuture; +import java.util.Collection; +import java.util.Optional; import java.util.concurrent.Callable; -import java.util.concurrent.ExecutionException; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import java.util.concurrent.Future; import java.util.concurrent.atomic.AtomicLong; - -import org.opendaylight.controller.config.yang.config.toaster_provider.impl.ToasterProviderRuntimeMXBean; -import org.opendaylight.controller.md.sal.common.api.data.DataChangeEvent; -import org.opendaylight.controller.sal.binding.api.NotificationProviderService; -import org.opendaylight.controller.sal.binding.api.data.DataBrokerService; -import org.opendaylight.controller.sal.binding.api.data.DataModificationTransaction; -import org.opendaylight.controller.sal.common.util.RpcErrors; -import org.opendaylight.controller.sal.common.util.Rpcs; +import java.util.concurrent.atomic.AtomicReference; +import org.opendaylight.controller.md.sal.common.util.jmx.AbstractMXBean; +import org.opendaylight.mdsal.binding.api.DataBroker; +import org.opendaylight.mdsal.binding.api.DataObjectModification; +import org.opendaylight.mdsal.binding.api.DataTreeChangeListener; +import org.opendaylight.mdsal.binding.api.DataTreeIdentifier; +import org.opendaylight.mdsal.binding.api.DataTreeModification; +import org.opendaylight.mdsal.binding.api.NotificationPublishService; +import org.opendaylight.mdsal.binding.api.ReadWriteTransaction; +import org.opendaylight.mdsal.binding.api.WriteTransaction; +import org.opendaylight.mdsal.common.api.CommitInfo; +import org.opendaylight.mdsal.common.api.OptimisticLockFailedException; +import org.opendaylight.mdsal.common.api.TransactionCommitFailedException; +import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.CancelToastInput; +import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.CancelToastOutput; +import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.CancelToastOutputBuilder; import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.DisplayString; import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.MakeToastInput; +import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.MakeToastOutput; +import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.MakeToastOutputBuilder; +import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.RestockToasterInput; +import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.RestockToasterOutput; +import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.RestockToasterOutputBuilder; import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.Toaster; import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.Toaster.ToasterStatus; -import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.RestockToasterInput; import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.ToasterBuilder; import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.ToasterOutOfBreadBuilder; import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.ToasterRestocked; import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.ToasterRestockedBuilder; import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.ToasterService; -import org.opendaylight.controller.sal.binding.api.data.DataChangeListener; -import org.opendaylight.yangtools.yang.binding.DataObject; +import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.controller.toaster.app.config.rev160503.ToasterAppConfig; +import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.controller.toaster.app.config.rev160503.ToasterAppConfigBuilder; +import org.opendaylight.yangtools.concepts.ListenerRegistration; import org.opendaylight.yangtools.yang.binding.InstanceIdentifier; import org.opendaylight.yangtools.yang.common.RpcError; import org.opendaylight.yangtools.yang.common.RpcError.ErrorType; import org.opendaylight.yangtools.yang.common.RpcResult; -import org.opendaylight.yangtools.yang.common.RpcError.ErrorSeverity; +import org.opendaylight.yangtools.yang.common.RpcResultBuilder; import org.slf4j.Logger; import org.slf4j.LoggerFactory; -import com.google.common.util.concurrent.Futures; +public class OpendaylightToaster extends AbstractMXBean + implements ToasterService, ToasterProviderRuntimeMXBean, DataTreeChangeListener, AutoCloseable { -public class OpendaylightToaster implements ToasterService, ToasterProviderRuntimeMXBean, - DataChangeListener, AutoCloseable { + private static final CancelToastOutput EMPTY_CANCEL_OUTPUT = new CancelToastOutputBuilder().build(); + private static final MakeToastOutput EMPTY_MAKE_OUTPUT = new MakeToastOutputBuilder().build(); + private static final RestockToasterOutput EMPTY_RESTOCK_OUTPUT = new RestockToasterOutputBuilder().build(); private static final Logger LOG = LoggerFactory.getLogger(OpendaylightToaster.class); - public static final InstanceIdentifier TOASTER_IID = InstanceIdentifier.builder(Toaster.class).build(); - + private static final InstanceIdentifier TOASTER_IID = InstanceIdentifier.builder(Toaster.class).build(); private static final DisplayString TOASTER_MANUFACTURER = new DisplayString("Opendaylight"); private static final DisplayString TOASTER_MODEL_NUMBER = new DisplayString("Model 1 - Binding Aware"); - private NotificationProviderService notificationProvider; - private DataBrokerService dataProvider; + private DataBroker dataBroker; + private NotificationPublishService notificationProvider; + private ListenerRegistration dataTreeChangeListenerRegistration; private final ExecutorService executor; - // As you will see we are using multiple threads here. Therefore we need to be careful about concurrency. - // In this case we use the taskLock to provide synchronization for the current task. - private volatile Future> currentTask; - private final Object taskLock = new Object(); - - private final AtomicLong amountOfBreadInStock = new AtomicLong( 100 ); + // This holds the Future for the current make toast task and is used to cancel the current toast. + private final AtomicReference> currentMakeToastTask = new AtomicReference<>(); + // Thread safe holders + private final AtomicLong amountOfBreadInStock = new AtomicLong(100); private final AtomicLong toastsMade = new AtomicLong(0); + private final AtomicLong darknessFactor = new AtomicLong(1000); - // Thread safe holder for our darkness multiplier. - private final AtomicLong darknessFactor = new AtomicLong( 1000 ); + private final ToasterAppConfig toasterAppConfig; public OpendaylightToaster() { + this(new ToasterAppConfigBuilder().setManufacturer(TOASTER_MANUFACTURER).setModelNumber(TOASTER_MODEL_NUMBER) + .setMaxMakeToastTries(2).build()); + } + + public OpendaylightToaster(final ToasterAppConfig toasterAppConfig) { + super("OpendaylightToaster", "toaster-provider", null); executor = Executors.newFixedThreadPool(1); + this.toasterAppConfig = toasterAppConfig; } - public void setNotificationProvider(NotificationProviderService salService) { - this.notificationProvider = salService; + public void setNotificationProvider(final NotificationPublishService notificationPublishService) { + this.notificationProvider = notificationPublishService; } - public void setDataProvider(DataBrokerService salDataProvider) { - this.dataProvider = salDataProvider; - updateStatus(); + public void setDataBroker(final DataBroker dataBroker) { + this.dataBroker = dataBroker; + } + + public void init() { + LOG.info("Initializing..."); + + Preconditions.checkNotNull(dataBroker, "dataBroker must be set"); + dataTreeChangeListenerRegistration = dataBroker.registerDataTreeChangeListener( + DataTreeIdentifier.create(CONFIGURATION, TOASTER_IID), this); + setToasterStatusUp(null); + + // Register our MXBean. + register(); } /** * Implemented from the AutoCloseable interface. */ @Override - public void close() throws ExecutionException, InterruptedException { + public void close() { + LOG.info("Closing..."); + + // Unregister our MXBean. + unregister(); + // When we close this service we need to shutdown our executor! executor.shutdown(); - if (dataProvider != null) { - final DataModificationTransaction t = dataProvider.beginTransaction(); - t.removeOperationalData(TOASTER_IID); - t.commit().get(); + if (dataTreeChangeListenerRegistration != null) { + dataTreeChangeListenerRegistration.close(); } - } - private Toaster buildToaster() { - // We don't need to synchronize on currentTask here b/c it's declared volatile and - // we're just doing a read. - boolean isUp = currentTask == null; + if (dataBroker != null) { + WriteTransaction tx = dataBroker.newWriteOnlyTransaction(); + tx.delete(OPERATIONAL,TOASTER_IID); + Futures.addCallback(tx.commit(), new FutureCallback() { + @Override + public void onSuccess(final CommitInfo result) { + LOG.debug("Successfully deleted the operational Toaster"); + } + + @Override + public void onFailure(final Throwable failure) { + LOG.error("Delete of the operational Toaster failed", failure); + } + }, MoreExecutors.directExecutor()); + } + } + private Toaster buildToaster(final ToasterStatus status) { // note - we are simulating a device whose manufacture and model are // fixed (embedded) into the hardware. // This is why the manufacture and model number are hardcoded. - ToasterBuilder tb = new ToasterBuilder(); - tb.setToasterManufacturer(TOASTER_MANUFACTURER).setToasterModelNumber(TOASTER_MODEL_NUMBER) - .setToasterStatus(isUp ? ToasterStatus.Up : ToasterStatus.Down); - return tb.build(); + return new ToasterBuilder().setToasterManufacturer(toasterAppConfig.getManufacturer()) + .setToasterModelNumber(toasterAppConfig.getModelNumber()).setToasterStatus(status).build(); } /** - * Implemented from the DataChangeListener interface. + * Implemented from the DataTreeChangeListener interface. */ @Override - public void onDataChanged( DataChangeEvent, DataObject> change ) { - DataObject dataObject = change.getUpdatedConfigurationData().get( TOASTER_IID ); - if( dataObject instanceof Toaster ) - { - Toaster toaster = (Toaster) dataObject; - Long darkness = toaster.getDarknessFactor(); - if( darkness != null ) - { - darknessFactor.set( darkness ); + public void onDataTreeChanged(final Collection> changes) { + for (DataTreeModification change: changes) { + DataObjectModification rootNode = change.getRootNode(); + if (rootNode.getModificationType() == WRITE) { + Toaster oldToaster = rootNode.getDataBefore(); + Toaster newToaster = rootNode.getDataAfter(); + LOG.info("onDataTreeChanged - Toaster config with path {} was added or replaced: " + + "old Toaster: {}, new Toaster: {}", change.getRootPath().getRootIdentifier(), + oldToaster, newToaster); + + Long darkness = newToaster.getDarknessFactor(); + if (darkness != null) { + darknessFactor.set(darkness); + } + } else if (rootNode.getModificationType() == DELETE) { + LOG.info("onDataTreeChanged - Toaster config with path {} was deleted: old Toaster: {}", + change.getRootPath().getRootIdentifier(), rootNode.getDataBefore()); } } } /** - * RestConf RPC call implemented from the ToasterService interface. + * RPC call implemented from the ToasterService interface that cancels the current toast, if any. */ @Override - public Future> cancelToast() { - synchronized (taskLock) { - if (currentTask != null) { - currentTask.cancel(true); - currentTask = null; - } + public ListenableFuture> cancelToast(final CancelToastInput input) { + Future current = currentMakeToastTask.getAndSet(null); + if (current != null) { + current.cancel(true); } - // Always return success from the cancel toast call. - return Futures.immediateFuture(Rpcs. getRpcResult(true, Collections. emptySet())); + + // Always return success from the cancel toast call + return Futures.immediateFuture(RpcResultBuilder.success(EMPTY_CANCEL_OUTPUT).build()); } /** - * RestConf RPC call implemented from the ToasterService interface. + * RPC call implemented from the ToasterService interface that attempts to make toast. */ @Override - public Future> makeToast(MakeToastInput input) { + public ListenableFuture> makeToast(final MakeToastInput input) { LOG.info("makeToast: " + input); - synchronized (taskLock) { - if (currentTask != null) { - // return an error since we are already toasting some toast. - LOG.info( "Toaster is already making toast" ); + final SettableFuture> futureResult = SettableFuture.create(); - RpcResult result = Rpcs. getRpcResult(false, null, Arrays.asList( - RpcErrors.getRpcError( "", "in-use", null, ErrorSeverity.WARNING, - "Toaster is busy", ErrorType.APPLICATION, null ) ) ); - return Futures.immediateFuture(result); - } - else if( outOfBread() ) { - RpcResult result = Rpcs. getRpcResult(false, null, Arrays.asList( - RpcErrors.getRpcError( "out-of-stock", "resource-denied", null, null, - "Toaster is out of bread", - ErrorType.APPLICATION, null ) ) ); - return Futures.immediateFuture(result); - } - else { - // Notice that we are moving the actual call to another thread, - // allowing this thread to return immediately. - // The MD-SAL design encourages asynchronus programming. If the - // caller needs to block until the call is - // complete then they can leverage the blocking methods on the - // Future interface. - currentTask = executor.submit(new MakeToastTask(input)); + checkStatusAndMakeToast(input, futureResult, toasterAppConfig.getMaxMakeToastTries()); + + return futureResult; + } + + private static RpcError makeToasterOutOfBreadError() { + return RpcResultBuilder.newError(APPLICATION, "resource-denied", "Toaster is out of bread", "out-of-stock", + null, null); + } + + private static RpcError makeToasterInUseError() { + return RpcResultBuilder.newWarning(APPLICATION, "in-use", "Toaster is busy", null, null, null); + } + + private void checkStatusAndMakeToast(final MakeToastInput input, + final SettableFuture> futureResult, final int tries) { + // Read the ToasterStatus and, if currently Up, try to write the status to Down. + // If that succeeds, then we essentially have an exclusive lock and can proceed + // to make toast. + final ReadWriteTransaction tx = dataBroker.newReadWriteTransaction(); + FluentFuture> readFuture = tx.read(OPERATIONAL, TOASTER_IID); + + final ListenableFuture commitFuture = + Futures.transformAsync(readFuture, toasterData -> { + ToasterStatus toasterStatus = ToasterStatus.Up; + if (toasterData.isPresent()) { + toasterStatus = toasterData.get().getToasterStatus(); + } + + LOG.debug("Read toaster status: {}", toasterStatus); + + if (toasterStatus == ToasterStatus.Up) { + + if (outOfBread()) { + LOG.debug("Toaster is out of bread"); + tx.cancel(); + return Futures.immediateFailedFuture( + new TransactionCommitFailedException("", makeToasterOutOfBreadError())); + } + + LOG.debug("Setting Toaster status to Down"); + + // We're not currently making toast - try to update the status to Down + // to indicate we're going to make toast. This acts as a lock to prevent + // concurrent toasting. + tx.put(OPERATIONAL, TOASTER_IID, buildToaster(ToasterStatus.Down)); + return tx.commit(); + } + + LOG.debug("Oops - already making toast!"); + + // Return an error since we are already making toast. This will get + // propagated to the commitFuture below which will interpret the null + // TransactionStatus in the RpcResult as an error condition. + tx.cancel(); + return Futures.immediateFailedFuture( + new TransactionCommitFailedException("", makeToasterInUseError())); + }, MoreExecutors.directExecutor()); + + Futures.addCallback(commitFuture, new FutureCallback() { + @Override + public void onSuccess(final CommitInfo result) { + // OK to make toast + currentMakeToastTask.set(executor.submit(new MakeToastTask(input, futureResult))); } - } - updateStatus(); - return currentTask; + @Override + public void onFailure(final Throwable ex) { + if (ex instanceof OptimisticLockFailedException) { + + // Another thread is likely trying to make toast simultaneously and updated the + // status before us. Try reading the status again - if another make toast is + // now in progress, we should get ToasterStatus.Down and fail. + + if (tries - 1 > 0) { + LOG.debug("Got OptimisticLockFailedException - trying again"); + checkStatusAndMakeToast(input, futureResult, tries - 1); + } else { + futureResult.set(RpcResultBuilder.failed() + .withError(ErrorType.APPLICATION, ex.getMessage()).build()); + } + } else if (ex instanceof TransactionCommitFailedException) { + LOG.debug("Failed to commit Toaster status", ex); + + // Probably already making toast. + futureResult.set(RpcResultBuilder.failed() + .withRpcErrors(((TransactionCommitFailedException)ex).getErrorList()).build()); + } else { + LOG.debug("Unexpected error committing Toaster status", ex); + futureResult.set(RpcResultBuilder.failed().withError(ErrorType.APPLICATION, + "Unexpected error committing Toaster status", ex).build()); + } + } + }, MoreExecutors.directExecutor()); } /** @@ -191,20 +321,18 @@ public class OpendaylightToaster implements ToasterService, ToasterProviderRunti * ToasterRestocked notification. */ @Override - public Future> restockToaster(RestockToasterInput input) { - LOG.info( "restockToaster: " + input ); + public ListenableFuture> restockToaster(final RestockToasterInput input) { + LOG.info("restockToaster: " + input); - synchronized( taskLock ) { - amountOfBreadInStock.set( input.getAmountOfBreadToStock() ); + amountOfBreadInStock.set(input.getAmountOfBreadToStock()); - if( amountOfBreadInStock.get() > 0 ) { - ToasterRestocked reStockedNotification = - new ToasterRestockedBuilder().setAmountOfBread( input.getAmountOfBreadToStock() ).build(); - notificationProvider.publish( reStockedNotification ); - } + if (amountOfBreadInStock.get() > 0) { + ToasterRestocked reStockedNotification = new ToasterRestockedBuilder() + .setAmountOfBread(input.getAmountOfBreadToStock()).build(); + notificationProvider.offerNotification(reStockedNotification); } - return Futures.immediateFuture(Rpcs. getRpcResult(true, Collections. emptySet())); + return Futures.immediateFuture(RpcResultBuilder.success(EMPTY_RESTOCK_OUTPUT).build()); } /** @@ -212,8 +340,8 @@ public class OpendaylightToaster implements ToasterService, ToasterProviderRunti */ @Override public void clearToastsMade() { - LOG.info( "clearToastsMade" ); - toastsMade.set( 0 ); + LOG.info("clearToastsMade"); + toastsMade.set(0); } /** @@ -224,66 +352,80 @@ public class OpendaylightToaster implements ToasterService, ToasterProviderRunti return toastsMade.get(); } - private void updateStatus() { - if (dataProvider != null) { - final DataModificationTransaction t = dataProvider.beginTransaction(); - t.removeOperationalData(TOASTER_IID); - t.putOperationalData(TOASTER_IID, buildToaster()); + private void setToasterStatusUp(final Function resultCallback) { + WriteTransaction tx = dataBroker.newWriteOnlyTransaction(); + tx.put(OPERATIONAL,TOASTER_IID, buildToaster(ToasterStatus.Up)); - try { - t.commit().get(); - } catch (InterruptedException | ExecutionException e) { - LOG.warn("Failed to update toaster status, operational otherwise", e); + Futures.addCallback(tx.commit(), new FutureCallback() { + @Override + public void onSuccess(final CommitInfo result) { + LOG.info("Successfully set ToasterStatus to Up"); + notifyCallback(true); } - } else { - LOG.trace("No data provider configured, not updating status"); - } + + @Override + public void onFailure(final Throwable failure) { + // We shouldn't get an OptimisticLockFailedException (or any ex) as no + // other component should be updating the operational state. + LOG.error("Failed to update toaster status", failure); + + notifyCallback(false); + } + + void notifyCallback(final boolean result) { + if (resultCallback != null) { + resultCallback.apply(result); + } + } + }, MoreExecutors.directExecutor()); } - private boolean outOfBread() - { + private boolean outOfBread() { return amountOfBreadInStock.get() == 0; } - private class MakeToastTask implements Callable> { + private class MakeToastTask implements Callable { final MakeToastInput toastRequest; + final SettableFuture> futureResult; - public MakeToastTask(MakeToastInput toast) { - toastRequest = toast; + MakeToastTask(final MakeToastInput toastRequest, + final SettableFuture> futureResult) { + this.toastRequest = toastRequest; + this.futureResult = futureResult; } @Override - public RpcResult call() { - try - { - // make toast just sleeps for n secondn per doneness level. - long darknessFactor = OpendaylightToaster.this.darknessFactor.get(); - Thread.sleep(darknessFactor * toastRequest.getToasterDoneness()); + public Void call() { + try { + // make toast just sleeps for n seconds per doneness level. + Thread.sleep(OpendaylightToaster.this.darknessFactor.get() * toastRequest.getToasterDoneness()); - } - catch( InterruptedException e ) { - LOG.info( "Interrupted while making the toast" ); + } catch (InterruptedException e) { + LOG.info("Interrupted while making the toast"); } toastsMade.incrementAndGet(); amountOfBreadInStock.getAndDecrement(); - if( outOfBread() ) { - LOG.info( "Toaster is out of bread!" ); - - notificationProvider.publish( new ToasterOutOfBreadBuilder().build() ); - } + if (outOfBread()) { + LOG.info("Toaster is out of bread!"); - synchronized (taskLock) { - currentTask = null; + notificationProvider.offerNotification(new ToasterOutOfBreadBuilder().build()); } - updateStatus(); + // Set the Toaster status back to up - this essentially releases the toasting lock. + // We can't clear the current toast task nor set the Future result until the + // update has been committed so we pass a callback to be notified on completion. - LOG.debug("Toast done"); + setToasterStatusUp(result -> { + currentMakeToastTask.set(null); + LOG.debug("Toast done"); + futureResult.set(RpcResultBuilder.success(EMPTY_MAKE_OUTPUT).build()); + return null; + }); - return Rpcs. getRpcResult(true, null, Collections. emptySet()); + return null; } } }