How to use

SystemDatasetInstantiator

in

co.cask.cdap.data.dataset

@Inject
public DatasetInstanceManager(TransactionSystemClientService txClientService,
               TransactionExecutorFactory txExecutorFactory,
               @Named("datasetMDS") DatasetFramework datasetFramework) {
 this.txExecutorFactory = txExecutorFactory;
 Map<String, String> emptyArgs = Collections.emptyMap();
 this.datasetCache = new MultiThreadDatasetCache(new SystemDatasetInstantiator(datasetFramework),
                         new TransactionSystemClientAdapter(txClientService),
                         NamespaceId.SYSTEM, emptyArgs, null,
                         ImmutableMap.of(
                          DatasetMetaTableUtil.INSTANCE_TABLE_NAME, emptyArgs
                         ));
}

public <T extends Dataset> T getDataset(DatasetId datasetId)
 throws DatasetInstantiationException {
 return getDataset(datasetId, DatasetDefinition.NO_ARGUMENTS);
}

 @Override
 public void close() throws IOException {
  datasetInstantiator.close();
  context.close();
 }
}

/**
 * Creates a new instance of a dataset based on the given information.
 */
private Dataset createDatasetInstance(DatasetCacheKey key, boolean recordLineage) {
 DatasetId datasetId = new DatasetId(key.getNamespace(), key.getName());
 Dataset dataset = instantiator.getDataset(datasetId, key.getArguments(), key.getAccessType());
 if (dataset instanceof MeteredDataset && metricsContext != null) {
  ((MeteredDataset) dataset).setMetricsCollector(
   metricsContext.childContext(Constants.Metrics.Tag.DATASET, key.getName()));
 }
 if (recordLineage) {
  instantiator.writeLineage(datasetId, key.getAccessType());
 }
 return dataset;
}

private <T> T performDatasetAdmin(final DatasetId datasetInstanceId, Operation<T> operation) throws Exception {
 try (SystemDatasetInstantiator datasetInstantiator = datasetInstantiatorFactory.create()) {
  DatasetAdmin admin = impersonator.doAs(datasetInstanceId, (Callable<DatasetAdmin>) () -> {
   DatasetAdmin admin1 = datasetInstantiator.getDatasetAdmin(datasetInstanceId);
   if (admin1 == null) {
    throw new NotFoundException("Couldn't obtain DatasetAdmin for dataset instance " + datasetInstanceId);
   }
   // returns a DatasetAdmin that executes operations as a particular user, for a particular namespace
   return new ImpersonatingDatasetAdmin(admin1, impersonator, datasetInstanceId);
  });
  try {
   return operation.perform(admin);
  } finally {
   Closeables.closeQuietly(admin);
  }
 }
}

/**
 * Creates a new instance of a dataset based on the given information.
 */
private Dataset createDatasetInstance(DatasetCacheKey key, boolean recordLineage) {
 DatasetId datasetId = new DatasetId(key.getNamespace(), key.getName());
 Dataset dataset = instantiator.getDataset(datasetId, key.getArguments(), key.getAccessType());
 if (dataset instanceof MeteredDataset && metricsContext != null) {
  ((MeteredDataset) dataset).setMetricsCollector(
   metricsContext.childContext(Constants.Metrics.Tag.DATASET, key.getName()));
 }
 if (recordLineage) {
  instantiator.writeLineage(datasetId, key.getAccessType());
 }
 return dataset;
}

private <T> T performDatasetAdmin(final DatasetId datasetInstanceId, Operation<T> operation) throws Exception {
 try (SystemDatasetInstantiator datasetInstantiator = datasetInstantiatorFactory.create()) {
  DatasetAdmin admin = impersonator.doAs(datasetInstanceId, (Callable<DatasetAdmin>) () -> {
   DatasetAdmin admin1 = datasetInstantiator.getDatasetAdmin(datasetInstanceId);
   if (admin1 == null) {
    throw new NotFoundException("Couldn't obtain DatasetAdmin for dataset instance " + datasetInstanceId);
   }
   // returns a DatasetAdmin that executes operations as a particular user, for a particular namespace
   return new ImpersonatingDatasetAdmin(admin1, impersonator, datasetInstanceId);
  });
  try {
   return operation.perform(admin);
  } finally {
   Closeables.closeQuietly(admin);
  }
 }
}

@Inject
public DatasetInstanceManager(TransactionSystemClientService txClientService,
               TransactionExecutorFactory txExecutorFactory,
               @Named("datasetMDS") DatasetFramework datasetFramework) {
 this.txExecutorFactory = txExecutorFactory;
 Map<String, String> emptyArgs = Collections.emptyMap();
 this.datasetCache = new MultiThreadDatasetCache(new SystemDatasetInstantiator(datasetFramework),
                         new TransactionSystemClientAdapter(txClientService),
                         NamespaceId.SYSTEM, emptyArgs, null,
                         ImmutableMap.of(
                          DatasetMetaTableUtil.INSTANCE_TABLE_NAME, emptyArgs
                         ));
}

public <T extends Dataset> T getDataset(DatasetId datasetId, Map<String, String> arguments)
 throws DatasetInstantiationException {
 return getDataset(datasetId, arguments, AccessType.UNKNOWN);
}

 @Override
 public void close() throws IOException {
  datasetInstantiator.close();
  context.close();
 }
}

 @Override
 public DynamicDatasetCache get() {
  SystemDatasetInstantiator dsInstantiator = new SystemDatasetInstantiator(dsFramework);
  return new MultiThreadDatasetCache(
   dsInstantiator, txClient, NamespaceId.SYSTEM, ImmutableMap.of(),
   metricsCollectionService.getContext(ImmutableMap.of()),
   ImmutableMap.of()
  );
 }
}

public <T extends Dataset> T getDataset(DatasetId datasetId, Map<String, String> arguments)
 throws DatasetInstantiationException {
 return getDataset(datasetId, arguments, AccessType.UNKNOWN);
}

 @Override
 public DynamicDatasetCache get() {
  SystemDatasetInstantiator dsInstantiator = new SystemDatasetInstantiator(dsFramework);
  return new MultiThreadDatasetCache(
   dsInstantiator, txClient, NamespaceId.SYSTEM, ImmutableMap.of(),
   metricsCollectionService.getContext(ImmutableMap.of()),
   ImmutableMap.of()
  );
 }
}

public <T extends Dataset> T getDataset(DatasetId datasetId)
 throws DatasetInstantiationException {
 return getDataset(datasetId, DatasetDefinition.NO_ARGUMENTS);
}

@Inject
public LocalRouteStore(DatasetFramework datasetFramework, TransactionSystemClient txClient) {
 this.datasetFramework = datasetFramework;
 this.transactional = Transactions.createTransactionalWithRetry(
  Transactions.createTransactional(new MultiThreadDatasetCache(
   new SystemDatasetInstantiator(datasetFramework), txClient,
   NamespaceId.SYSTEM, ImmutableMap.<String, String>of(), null, null)), RetryStrategies.retryOnConflict(20, 100));
}

public void initialize() throws IOException, DatasetManagementException,
 DatasetNotFoundException, ClassNotFoundException {
 dataset = datasetInstantiator.getDataset(datasetId);
 if (dataset instanceof TransactionAware) {
  ((TransactionAware) dataset).startTx(transaction);
 }
}

@VisibleForTesting
public DefaultFieldLineageReader(DatasetFramework datasetFramework, TransactionSystemClient txClient,
                 DatasetId fieldLineageDatasetId) {
 this.datasetFramework = datasetFramework;
 this.fieldLineageDatasetId = fieldLineageDatasetId;
 this.transactional = Transactions.createTransactional(new MultiThreadDatasetCache(
  new SystemDatasetInstantiator(datasetFramework), new TransactionSystemClientAdapter(txClient),
  NamespaceId.SYSTEM, ImmutableMap.of(), null, null));
}

public void initialize() throws IOException, DatasetManagementException,
 DatasetNotFoundException, ClassNotFoundException {
 dataset = datasetInstantiator.getDataset(datasetId);
 if (dataset instanceof TransactionAware) {
  ((TransactionAware) dataset).startTx(transaction);
 }
}

@Inject
public MDSViewStore(DatasetFramework datasetFramework, TransactionSystemClient txClient) {
 this.datasetFramework = datasetFramework;
 this.transactional = Transactions.createTransactionalWithRetry(
  Transactions.createTransactional(new MultiThreadDatasetCache(
   new SystemDatasetInstantiator(datasetFramework), txClient,
   NamespaceId.SYSTEM, ImmutableMap.<String, String>of(), null, null)),
  RetryStrategies.retryOnConflict(20, 100)
 );
}

private String generateEnableStatement(DatasetId datasetId, DatasetSpecification spec, boolean truncating)
 throws UnsupportedTypeException, ExploreException {
 try (SystemDatasetInstantiator datasetInstantiator = datasetInstantiatorFactory.create()) {
  Dataset dataset = datasetInstantiator.getDataset(datasetId);
  try {
   return generateEnableStatement(dataset, spec, datasetId,
                   tableNaming.getTableName(datasetId, spec.getProperties()), truncating);
  } finally {
   Closeables.closeQuietly(dataset);
  }
 } catch (IOException e) {
  throw new ExploreException("Exception while trying to instantiate dataset " + datasetId, e);
 }
}