com.microsoft.azure.storage.blob.BlobListingDetails Java Examples

private void deleteStaleBlobs() throws Exception {
    final Date expiryDate = Date.from(ZonedDateTime.now().minusWeeks(1).toInstant());

    final CloudBlobDirectory directoryReference = blobContainer.getDirectoryReference(request.storageLocation.clusterId + "/" + request.storageLocation.datacenterId);

    for (final ListBlobItem blob : directoryReference.listBlobs(null, true, EnumSet.noneOf(BlobListingDetails.class), null, null)) {
        if (!(blob instanceof CloudBlob)) {
            continue;
        }

        final BlobProperties properties = ((CloudBlob) blob).getProperties();
        if (properties == null || properties.getLastModified() == null) {
            continue;
        }

        if (properties.getLastModified().before(expiryDate)) {
            ((CloudBlob) blob).delete();
        }
    }
}
 

public Set<String> children(String account, String container, BlobPath path) throws URISyntaxException, StorageException {
    final var blobsBuilder = new HashSet<String>();
    final Tuple<CloudBlobClient, Supplier<OperationContext>> client = client();
    final CloudBlobContainer blobContainer = client.v1().getContainerReference(container);
    final String keyPath = path.buildAsString();
    final EnumSet<BlobListingDetails> enumBlobListingDetails = EnumSet.of(BlobListingDetails.METADATA);

    for (ListBlobItem blobItem : blobContainer.listBlobs(keyPath, false, enumBlobListingDetails, null, client.v2().get())) {
        if (blobItem instanceof CloudBlobDirectory) {
            final URI uri = blobItem.getUri();
            LOGGER.trace(() -> new ParameterizedMessage("blob url [{}]", uri));
            // uri.getPath is of the form /container/keyPath.* and we want to strip off the /container/
            // this requires 1 + container.length() + 1, with each 1 corresponding to one of the /.
            // Lastly, we add the length of keyPath to the offset to strip this container's path.
            final String uriPath = uri.getPath();
            blobsBuilder.add(uriPath.substring(1 + container.length() + 1 + keyPath.length(), uriPath.length() - 1));
        }
    }
    return Set.copyOf(blobsBuilder);
}
 

private Iterable<ListBlobItem> list(final Path prefix) {
    final String blobPrefix = Paths.get(request.storageLocation.clusterId)
        .resolve(request.storageLocation.datacenterId)
        .resolve(request.storageLocation.nodeId)
        .resolve(prefix).toString();

    return blobContainer.listBlobs(blobPrefix, true, EnumSet.noneOf(BlobListingDetails.class), null, null);
}
 

public Map<String, BlobMetaData> listBlobsByPrefix(String container, String keyPath, String prefix)
    throws URISyntaxException, StorageException {
    // NOTE: this should be here: if (prefix == null) prefix = "";
    // however, this is really inefficient since deleteBlobsByPrefix enumerates everything and
    // then does a prefix match on the result; it should just call listBlobsByPrefix with the prefix!
    final var blobsBuilder = new HashMap<String, BlobMetaData>();
    final EnumSet<BlobListingDetails> enumBlobListingDetails = EnumSet.of(BlobListingDetails.METADATA);
    final Tuple<CloudBlobClient, Supplier<OperationContext>> client = client();
    final CloudBlobContainer blobContainer = client.v1().getContainerReference(container);
    LOGGER.trace(() -> new ParameterizedMessage("listing container [{}], keyPath [{}], prefix [{}]", container, keyPath, prefix));
    for (final ListBlobItem blobItem : blobContainer.listBlobs(keyPath + (prefix == null ? "" : prefix), false,
        enumBlobListingDetails, null, client.v2().get())) {
        final URI uri = blobItem.getUri();
        LOGGER.trace(() -> new ParameterizedMessage("blob url [{}]", uri));
        // uri.getPath is of the form /container/keyPath.* and we want to strip off the /container/
        // this requires 1 + container.length() + 1, with each 1 corresponding to one of the /
        final String blobPath = uri.getPath().substring(1 + container.length() + 1);
        if (blobItem instanceof CloudBlob) {
            final BlobProperties properties = ((CloudBlob) blobItem).getProperties();
            final String name = blobPath.substring(keyPath.length());
            LOGGER.trace(() -> new ParameterizedMessage("blob url [{}], name [{}], size [{}]", uri, name, properties.getLength()));
            blobsBuilder.put(name, new PlainBlobMetaData(name, properties.getLength()));
        }
    }

    return Map.copyOf(blobsBuilder);
}
 

public void deleteFiles(String container, String path) throws URISyntaxException, StorageException {
    final Tuple<CloudBlobClient, Supplier<OperationContext>> client = client();
    // container name must be lower case.
    LOGGER.trace(() -> new ParameterizedMessage("delete files container [{}], path [{}]", container, path));
    // list the blobs using a flat blob listing mode
    final CloudBlobContainer blobContainer = client.v1().getContainerReference(container);
    for (final ListBlobItem blobItem : blobContainer.listBlobs(path, true, EnumSet.noneOf(BlobListingDetails.class), null,
        client.v2().get())) {
        final String blobName = blobNameFromUri(blobItem.getUri());
        LOGGER.trace(() -> new ParameterizedMessage("removing blob [{}] full URI was [{}]", blobName, blobItem.getUri()));
        // don't call {@code #deleteBlob}, use the same client
        final CloudBlockBlob azureBlob = blobContainer.getBlockBlobReference(blobName);
        azureBlob.delete(DeleteSnapshotsOption.NONE, null, null, client.v2().get());
    }
}
 

protected LogBlobIterable(final CloudBlobDirectory logDirectory, final Date startTime, final Date endTime,
        final EnumSet<LoggingOperations> operations, final EnumSet<BlobListingDetails> details,
        final BlobRequestOptions options, final OperationContext opContext) {
    this.logDirectory = logDirectory;
    this.startTime = startTime;
    this.endTime = endTime;
    this.operations = operations;
    this.details = details;
    this.options = options;
    this.opContext = opContext;
}
 

public LogBlobIterator(final CloudBlobDirectory logDirectory, final Date startDate, final Date endDate,
        final EnumSet<LoggingOperations> operations, final EnumSet<BlobListingDetails> details,
        final BlobRequestOptions options, final OperationContext opContext) {
    TimeZone gmtTime = TimeZone.getTimeZone("GMT");
    HOUR_FORMAT.setTimeZone(gmtTime);
    DAY_FORMAT.setTimeZone(gmtTime);
    MONTH_FORMAT.setTimeZone(gmtTime);
    YEAR_FORMAT.setTimeZone(gmtTime);

    this.logDirectory = logDirectory;
    this.operations = operations;
    this.details = details;
    this.opContext = opContext;

    if (options == null) {
        this.options = new BlobRequestOptions();
    }
    else {
        this.options = options;
    }

    if (startDate != null) {
        this.startDate = new GregorianCalendar();
        this.startDate.setTime(startDate);
        this.startDate.add(GregorianCalendar.MINUTE, (-this.startDate.get(GregorianCalendar.MINUTE)));
        this.startDate.setTimeZone(gmtTime);
    }
    if (endDate != null) {
        this.endDate = new GregorianCalendar();
        this.endDate.setTime(endDate);
        this.endDate.setTimeZone(gmtTime);
        this.endPrefix = this.logDirectory.getPrefix() + HOUR_FORMAT.format(this.endDate.getTime());
    }
}
 

/**
 * Returns an enumerable collection of log blobs, retrieved lazily.
 * 
 * @param service
 *            A {@link StorageService} enumeration value that indicates which storage service to use.
 * @param startTime
 *            A <code>java.util.Date</code> object representing the start of the time range for which logs should
 *            be retrieved.
 * @param endTime
 *            A <code>java.util.Date</code> object representing the end of the time range for which logs should
 *            be retrieved.
 * @param operations
 *            A {@link LoggingOperations} enumeration set that indicates which log types to return.
 * @param details
 *            A {@link BlobListingDetails} enumeration set that indicates whether or not blob metadata should
 *            be returned. None or METADATA are the only valid values.
 * @param options
 *            A {@link BlobRequestOptions} object that specifies additional options for the request.
 * @param operationContext
 *            An {@link OperationContext} object that represents the context for the current operation.
 * @return
 *         An enumerable collection of objects that implement {@link ListBlobItem} and are retrieved lazily.
 * @throws StorageException
 * @throws URISyntaxException
 */
public Iterable<ListBlobItem> listLogBlobs(StorageService service, Date startTime, Date endTime,
        EnumSet<LoggingOperations> operations, BlobListingDetails details, BlobRequestOptions options,
        OperationContext operationContext) throws StorageException, URISyntaxException {
    Utility.assertNotNull("service", service);
    if (operations == null) {
        operations = EnumSet.allOf(LoggingOperations.class);
    }

    if (!(details == null || details.equals(BlobListingDetails.METADATA))) {
        throw new IllegalArgumentException(SR.INVALID_LISTING_DETAILS);
    }

    if (operations.equals(EnumSet.noneOf(LoggingOperations.class))) {
        throw new IllegalArgumentException(SR.INVALID_LOGGING_LEVEL);
    }

    EnumSet<BlobListingDetails> metadataDetails;
    if (details != null
            && (details.equals(BlobListingDetails.METADATA) || !operations.equals(EnumSet
                    .allOf(LoggingOperations.class)))) {
        metadataDetails = EnumSet.of(BlobListingDetails.METADATA);
    }
    else {
        metadataDetails = EnumSet.noneOf(BlobListingDetails.class);
    }

    return new LogBlobIterable(this.getLogDirectory(service), startTime, endTime, operations, metadataDetails,
            options, operationContext);
}
 

public Iterable<ListBlobItem> listBlobs(final String containerName, final String prefix, final boolean useFlatBlobListing)
        throws URISyntaxException, StorageException, InvalidKeyException {
    CloudBlobClient cloudBlobClient = connection.getCloudStorageAccount().createCloudBlobClient();
    CloudBlobContainer cloudBlobContainer = cloudBlobClient.getContainerReference(containerName);
    return cloudBlobContainer.listBlobs(prefix, useFlatBlobListing, EnumSet.noneOf(BlobListingDetails.class), null,
            AzureStorageUtils.getTalendOperationContext());
}
 

@Override
public Iterable<ListBlobItem> listBlobs(String prefix,
    boolean useFlatBlobListing, EnumSet<BlobListingDetails> listingDetails,
    BlobRequestOptions options, OperationContext opContext)
    throws URISyntaxException, StorageException {
  return WrappingIterator.wrap(directory.listBlobs(prefix,
      useFlatBlobListing, listingDetails, options, opContext));
}
 

@Override
public Iterable<ListBlobItem> listBlobs(String prefix,
    boolean useFlatBlobListing, EnumSet<BlobListingDetails> listingDetails,
    BlobRequestOptions options, OperationContext opContext)
    throws URISyntaxException, StorageException {
  return WrappingIterator.wrap(directory.listBlobs(prefix,
      useFlatBlobListing, listingDetails, options, opContext));
}
 

@Override
public Iterable<ListBlobItem> listBlobs(String prefix,
    boolean useFlatBlobListing, EnumSet<BlobListingDetails> listingDetails,
    BlobRequestOptions options, OperationContext opContext)
    throws URISyntaxException, StorageException {
  ArrayList<ListBlobItem> ret = new ArrayList<ListBlobItem>();
  URI searchUri = null;
  if (prefix == null) {
    searchUri = uri;
  } else {
    try {
      searchUri = UriBuilder.fromUri(uri).path(prefix).build();
    } catch (UriBuilderException e) {
      throw new AssertionError("Failed to encode path: " + prefix);
    }
  }

  String fullPrefix = convertUriToDecodedString(searchUri);
  boolean includeMetadata = listingDetails.contains(BlobListingDetails.METADATA);
  HashSet<String> addedDirectories = new HashSet<String>();
  for (InMemoryBlockBlobStore.ListBlobEntry current : backingStore.listBlobs(
      fullPrefix, includeMetadata)) {
    int indexOfSlash = current.getKey().indexOf('/', fullPrefix.length());
    if (useFlatBlobListing || indexOfSlash < 0) {
      if (current.isPageBlob()) {
        ret.add(new MockCloudPageBlobWrapper(
            convertKeyToEncodedUri(current.getKey()),
            current.getMetadata(),
            current.getContentLength()));
      } else {
      ret.add(new MockCloudBlockBlobWrapper(
          convertKeyToEncodedUri(current.getKey()),
          current.getMetadata(),
          current.getContentLength()));
      }
    } else {
      String directoryName = current.getKey().substring(0, indexOfSlash);
      if (!addedDirectories.contains(directoryName)) {
        addedDirectories.add(current.getKey());
        ret.add(new MockCloudBlobDirectoryWrapper(new URI(
            directoryName + "/")));
      }
    }
  }
  return ret;
}
 

@Override
public Iterable<ListBlobItem> listBlobs(String prefix,
    boolean useFlatBlobListing, EnumSet<BlobListingDetails> listingDetails,
    BlobRequestOptions options, OperationContext opContext)
    throws URISyntaxException, StorageException {
  ArrayList<ListBlobItem> ret = new ArrayList<ListBlobItem>();
  URI searchUri = null;
  if (prefix == null) {
    searchUri = uri;
  } else {
    try {
      searchUri = UriBuilder.fromUri(uri).path(prefix).build();
    } catch (UriBuilderException e) {
      throw new AssertionError("Failed to encode path: " + prefix);
    }
  }

  String fullPrefix = convertUriToDecodedString(searchUri);
  boolean includeMetadata = listingDetails.contains(BlobListingDetails.METADATA);
  HashSet<String> addedDirectories = new HashSet<String>();
  for (InMemoryBlockBlobStore.ListBlobEntry current : backingStore.listBlobs(
      fullPrefix, includeMetadata)) {
    int indexOfSlash = current.getKey().indexOf('/', fullPrefix.length());
    if (useFlatBlobListing || indexOfSlash < 0) {
      if (current.isPageBlob()) {
        ret.add(new MockCloudPageBlobWrapper(
            convertKeyToEncodedUri(current.getKey()),
            current.getMetadata(),
            current.getContentLength()));
      } else {
      ret.add(new MockCloudBlockBlobWrapper(
          convertKeyToEncodedUri(current.getKey()),
          current.getMetadata(),
          current.getContentLength()));
      }
    } else {
      String directoryName = current.getKey().substring(0, indexOfSlash);
      if (!addedDirectories.contains(directoryName)) {
        addedDirectories.add(current.getKey());
        ret.add(new MockCloudBlobDirectoryWrapper(new URI(
            directoryName + "/")));
      }
    }
  }
  return ret;
}
 

@Override
protected List<BlobInfo> performListing(final ProcessContext context, final Long minTimestamp) throws IOException {
    String containerName = context.getProperty(AzureStorageUtils.CONTAINER).evaluateAttributeExpressions().getValue();
    String prefix = context.getProperty(PROP_PREFIX).evaluateAttributeExpressions().getValue();
    if (prefix == null) {
        prefix = "";
    }
    final List<BlobInfo> listing = new ArrayList<>();
    try {
        CloudBlobClient blobClient = AzureStorageUtils.createCloudBlobClient(context, getLogger(), null);
        CloudBlobContainer container = blobClient.getContainerReference(containerName);

        final OperationContext operationContext = new OperationContext();
        AzureStorageUtils.setProxy(operationContext, context);

        for (ListBlobItem blob : container.listBlobs(prefix, true, EnumSet.of(BlobListingDetails.METADATA), null, operationContext)) {
            if (blob instanceof CloudBlob) {
                CloudBlob cloudBlob = (CloudBlob) blob;
                BlobProperties properties = cloudBlob.getProperties();
                StorageUri uri = cloudBlob.getSnapshotQualifiedStorageUri();

                Builder builder = new BlobInfo.Builder()
                                          .primaryUri(uri.getPrimaryUri().toString())
                                          .blobName(cloudBlob.getName())
                                          .containerName(containerName)
                                          .contentType(properties.getContentType())
                                          .contentLanguage(properties.getContentLanguage())
                                          .etag(properties.getEtag())
                                          .lastModifiedTime(properties.getLastModified().getTime())
                                          .length(properties.getLength());

                if (uri.getSecondaryUri() != null) {
                    builder.secondaryUri(uri.getSecondaryUri().toString());
                }

                if (blob instanceof CloudBlockBlob) {
                    builder.blobType(AzureStorageUtils.BLOCK);
                } else {
                    builder.blobType(AzureStorageUtils.PAGE);
                }
                listing.add(builder.build());
            }
        }
    } catch (Throwable t) {
        throw new IOException(ExceptionUtils.getRootCause(t));
    }
    return listing;
}
 

/**
 * This private method uses the root directory or the original container to
 * list blobs under the directory or container depending on whether the
 * original file system object was constructed with a short- or long-form URI.
 * If the root directory is non-null the URI in the file constructor was in
 * the long form.
 * 
 * @param includeMetadata
 *          if set, the listed items will have their metadata populated
 *          already.
 * 
 * @returns blobItems : iterable collection of blob items.
 * @throws URISyntaxException
 * 
 */
private Iterable<ListBlobItem> listRootBlobs(boolean includeMetadata)
    throws StorageException, URISyntaxException {
  return rootDirectory.listBlobs(
      null, false,
      includeMetadata ?
          EnumSet.of(BlobListingDetails.METADATA) :
            EnumSet.noneOf(BlobListingDetails.class),
      null,
            getInstrumentedContext());
}
 

/**
 * This private method uses the root directory or the original container to
 * list blobs under the directory or container given a specified prefix for
 * the directory depending on whether the original file system object was
 * constructed with a short- or long-form URI. If the root directory is
 * non-null the URI in the file constructor was in the long form.
 * 
 * @param aPrefix
 *          : string name representing the prefix of containing blobs.
 * @param includeMetadata
 *          if set, the listed items will have their metadata populated
 *          already.
 * 
 * @returns blobItems : iterable collection of blob items.
 * @throws URISyntaxException
 * 
 */
private Iterable<ListBlobItem> listRootBlobs(String aPrefix,
    boolean includeMetadata) throws StorageException, URISyntaxException {

  Iterable<ListBlobItem> list = rootDirectory.listBlobs(aPrefix,
      false,
      includeMetadata ?
          EnumSet.of(BlobListingDetails.METADATA) :
            EnumSet.noneOf(BlobListingDetails.class),
            null,
            getInstrumentedContext());
  return list;
}
 

/**
 * This private method uses the root directory or the original container to
 * list blobs under the directory or container given a specified prefix for
 * the directory depending on whether the original file system object was
 * constructed with a short- or long-form URI. It also uses the specified flat
 * or hierarchical option, listing details options, request options, and
 * operation context.
 * 
 * @param aPrefix
 *          string name representing the prefix of containing blobs.
 * @param useFlatBlobListing
 *          - the list is flat if true, or hierarchical otherwise.
 * @param listingDetails
 *          - determine whether snapshots, metadata, committed/uncommitted
 *          data
 * @param options
 *          - object specifying additional options for the request. null =
 *          default options
 * @param opContext
 *          - context of the current operation
 * @returns blobItems : iterable collection of blob items.
 * @throws URISyntaxException
 * 
 */
private Iterable<ListBlobItem> listRootBlobs(String aPrefix, boolean useFlatBlobListing,
    EnumSet<BlobListingDetails> listingDetails, BlobRequestOptions options,
    OperationContext opContext) throws StorageException, URISyntaxException {

  CloudBlobDirectoryWrapper directory =  this.container.getDirectoryReference(aPrefix);
  return directory.listBlobs(
      null,
      useFlatBlobListing,
      listingDetails,
      options,
      opContext);
}
 

/**
 * Returns an enumerable collection of log records, retrieved lazily.
 * 
 * @param service
 *            A {@link StorageService} enumeration value that indicates which storage service to use.
 * @param startTime
 *            A <code>java.util.Date</code> object representing the start of the time range for which logs should
 *            be retrieved.
 * @param endTime
 *            A <code>java.util.Date</code> object representing the end of the time range for which logs should
 *            be retrieved.
 * @param options
 *            A {@link BlobRequestOptions} object that specifies additional options for the request.
 * @param operationContext
 *            An {@link OperationContext} object that represents the context for the current operation.
 * @return
 *         An enumerable collection of objects that implement {@link ListBlobItem} and are retrieved lazily.
 * @throws StorageException
 * @throws URISyntaxException
 */
public Iterable<LogRecord> listLogRecords(StorageService service, Date startTime, Date endTime,
        BlobRequestOptions options, OperationContext operationContext) throws StorageException, URISyntaxException {
    Utility.assertNotNull("service", service);
    EnumSet<LoggingOperations> operations = EnumSet.allOf(LoggingOperations.class);
    EnumSet<BlobListingDetails> metadataDetails = EnumSet.noneOf(BlobListingDetails.class);
    Iterator<ListBlobItem> blobIterator = new LogBlobIterable(this.getLogDirectory(service), startTime, endTime,
            operations, metadataDetails, options, operationContext).iterator();

    return new LogRecordIterable(blobIterator);
}
 

/**
 * This private method uses the root directory or the original container to
 * list blobs under the directory or container given a specified prefix for
 * the directory depending on whether the original file system object was
 * constructed with a short- or long-form URI. It also uses the specified flat
 * or hierarchical option, listing details options, request options, and
 * operation context.
 * 
 * @param aPrefix
 *          string name representing the prefix of containing blobs.
 * @param useFlatBlobListing
 *          - the list is flat if true, or hierarchical otherwise.
 * @param listingDetails
 *          - determine whether snapshots, metadata, committed/uncommitted
 *          data
 * @param options
 *          - object specifying additional options for the request. null =
 *          default options
 * @param opContext
 *          - context of the current operation
 * @returns blobItems : iterable collection of blob items.
 * @throws URISyntaxException
 * 
 */
private Iterable<ListBlobItem> listRootBlobs(String aPrefix, boolean useFlatBlobListing,
    EnumSet<BlobListingDetails> listingDetails, BlobRequestOptions options,
    OperationContext opContext) throws StorageException, URISyntaxException {

  CloudBlobDirectoryWrapper directory =  this.container.getDirectoryReference(aPrefix);
  return directory.listBlobs(
      null,
      useFlatBlobListing,
      listingDetails,
      options,
      opContext);
}
 

/**
 * This private method uses the root directory or the original container to
 * list blobs under the directory or container given a specified prefix for
 * the directory depending on whether the original file system object was
 * constructed with a short- or long-form URI. If the root directory is
 * non-null the URI in the file constructor was in the long form.
 * 
 * @param aPrefix
 *          : string name representing the prefix of containing blobs.
 * @param includeMetadata
 *          if set, the listed items will have their metadata populated
 *          already.
 * 
 * @returns blobItems : iterable collection of blob items.
 * @throws URISyntaxException
 * 
 */
private Iterable<ListBlobItem> listRootBlobs(String aPrefix,
    boolean includeMetadata) throws StorageException, URISyntaxException {

  Iterable<ListBlobItem> list = rootDirectory.listBlobs(aPrefix,
      false,
      includeMetadata ?
          EnumSet.of(BlobListingDetails.METADATA) :
            EnumSet.noneOf(BlobListingDetails.class),
            null,
            getInstrumentedContext());
  return list;
}
 

/**
 * This private method uses the root directory or the original container to
 * list blobs under the directory or container depending on whether the
 * original file system object was constructed with a short- or long-form URI.
 * If the root directory is non-null the URI in the file constructor was in
 * the long form.
 * 
 * @param includeMetadata
 *          if set, the listed items will have their metadata populated
 *          already.
 * 
 * @returns blobItems : iterable collection of blob items.
 * @throws URISyntaxException
 * 
 */
private Iterable<ListBlobItem> listRootBlobs(boolean includeMetadata)
    throws StorageException, URISyntaxException {
  return rootDirectory.listBlobs(
      null, false,
      includeMetadata ?
          EnumSet.of(BlobListingDetails.METADATA) :
            EnumSet.noneOf(BlobListingDetails.class),
      null,
            getInstrumentedContext());
}
 

/**
 * Returns an enumerable collection of blob items whose names begin with the
 * specified prefix, using the specified flat or hierarchical option,
 * listing details options, request options, and operation context.
 * 
 * @param prefix
 *          A <code>String</code> that represents the prefix of the blob
 *          name.
 * @param useFlatBlobListing
 *          <code>true</code> to indicate that the returned list will be
 *          flat; <code>false</code> to indicate that the returned list will
 *          be hierarchical.
 * @param listingDetails
 *          A <code>java.util.EnumSet</code> object that contains
 *          {@link BlobListingDetails} values that indicate whether
 *          snapshots, metadata, and/or uncommitted blocks are returned.
 *          Committed blocks are always returned.
 * @param options
 *          A {@link BlobRequestOptions} object that specifies any
 *          additional options for the request. Specifying <code>null</code>
 *          will use the default request options from the associated service
 *          client ( {@link CloudBlobClient}).
 * @param opContext
 *          An {@link OperationContext} object that represents the context
 *          for the current operation. This object is used to track requests
 *          to the storage service, and to provide additional runtime
 *          information about the operation.
 * 
 * @return An enumerable collection of {@link ListBlobItem} objects that
 *         represent the block items whose names begin with the specified
 *         prefix in this directory.
 * 
 * @throws StorageException
 *           If a storage service error occurred.
 * @throws URISyntaxException
 *           If the resource URI is invalid.
 */
public abstract Iterable<ListBlobItem> listBlobs(String prefix,
    boolean useFlatBlobListing, EnumSet<BlobListingDetails> listingDetails,
    BlobRequestOptions options, OperationContext opContext)
    throws URISyntaxException, StorageException;
 

/**
 * Returns an enumerable collection of blob items whose names begin with the
 * specified prefix, using the specified flat or hierarchical option,
 * listing details options, request options, and operation context.
 * 
 * @param prefix
 *          A <code>String</code> that represents the prefix of the blob
 *          name.
 * @param useFlatBlobListing
 *          <code>true</code> to indicate that the returned list will be
 *          flat; <code>false</code> to indicate that the returned list will
 *          be hierarchical.
 * @param listingDetails
 *          A <code>java.util.EnumSet</code> object that contains
 *          {@link BlobListingDetails} values that indicate whether
 *          snapshots, metadata, and/or uncommitted blocks are returned.
 *          Committed blocks are always returned.
 * @param options
 *          A {@link BlobRequestOptions} object that specifies any
 *          additional options for the request. Specifying <code>null</code>
 *          will use the default request options from the associated service
 *          client ( {@link CloudBlobClient}).
 * @param opContext
 *          An {@link OperationContext} object that represents the context
 *          for the current operation. This object is used to track requests
 *          to the storage service, and to provide additional runtime
 *          information about the operation.
 * 
 * @return An enumerable collection of {@link ListBlobItem} objects that
 *         represent the block items whose names begin with the specified
 *         prefix in this directory.
 * 
 * @throws StorageException
 *           If a storage service error occurred.
 * @throws URISyntaxException
 *           If the resource URI is invalid.
 */
public abstract Iterable<ListBlobItem> listBlobs(String prefix,
    boolean useFlatBlobListing, EnumSet<BlobListingDetails> listingDetails,
    BlobRequestOptions options, OperationContext opContext)
    throws URISyntaxException, StorageException;