org.kitesdk.data.hcatalog
Class HCatalogDatasetRepository

java.lang.Object
  org.kitesdk.data.spi.AbstractDatasetRepository
      org.kitesdk.data.spi.filesystem.FileSystemDatasetRepository
          org.kitesdk.data.hcatalog.HCatalogDatasetRepository

All Implemented Interfaces:

DatasetRepository, org.kitesdk.data.spi.TemporaryDatasetRepositoryAccessor

public class HCatalogDatasetRepository
extends org.kitesdk.data.spi.filesystem.FileSystemDatasetRepository

A DatasetRepository that uses the Hive/HCatalog metastore for metadata, and stores data in a Hadoop FileSystem.

The location of the data directory is either chosen by Hive/HCatalog (so called "managed tables"), or specified when creating an instance of this class by providing a FileSystem, and a root directory in the constructor ("external tables").

The primary methods of interest will be create(String, DatasetDescriptor), AbstractDatasetRepository.load(String), and delete(String) which create a new dataset, load an existing dataset, or delete an existing dataset, respectively. Once a dataset has been created or loaded, users can invoke the appropriate Dataset methods to get a reader or writer as needed.

See Also:

DatasetRepository, Dataset

Nested Class Summary

static class

HCatalogDatasetRepository.Builder A fluent builder to aid in the construction of HCatalogDatasetRepository instances.

Method Summary

<E> Dataset<E>	create(String name, DatasetDescriptor descriptor) Create a Dataset with the supplied descriptor.
boolean	delete(String name) Delete data for the Dataset named name and remove its DatasetDescriptor from the underlying metadata provider.
URI	getUri() Return the URI of this repository.

Methods inherited from class org.kitesdk.data.spi.filesystem.FileSystemDatasetRepository

create, exists, getTemporaryRepository, list, load, partitionKeyForPath, toString, update

Methods inherited from class org.kitesdk.data.spi.AbstractDatasetRepository

load, update

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Method Detail

create

public <E> Dataset<E> create(String name,
                             DatasetDescriptor descriptor)

Description copied from interface: DatasetRepository

Create a Dataset with the supplied descriptor. Depending on the underlying dataset storage, some schema types or configurations might not be supported. If you supply an illegal schema, the implementing class throws an exception. It is illegal to create more than one dataset with the same name. If you provide a duplicate name, the implementing class throws an exception.

Specified by:

create in interface DatasetRepository

Overrides:

create in class org.kitesdk.data.spi.AbstractDatasetRepository

Parameters:

name - The fully qualified dataset name

descriptor - A descriptor that describes the schema and other properties of the dataset

Returns:

The newly created dataset

delete

public boolean delete(String name)

Description copied from interface: DatasetRepository

Delete data for the Dataset named name and remove its DatasetDescriptor from the underlying metadata provider. After this method is called, there is no Dataset with the given name, unless an exception is thrown. If either data or metadata are removed, this method returns true. If there is no Dataset corresponding to the given name, this method makes no changes and returns false.

Specified by:

delete in interface DatasetRepository

Overrides:

delete in class org.kitesdk.data.spi.filesystem.FileSystemDatasetRepository

Parameters:

name - The name of the dataset to delete.

Returns:

true if any data or metadata is removed, false if no action is taken.

getUri

public URI getUri()

Description copied from interface: DatasetRepository

Return the URI of this repository. When used with the DatasetRepositories.open(java.net.URI) (or DatasetRepositories.openRandomAccess(java.net.URI)) method, an equivalent DatasetRepository object to this is returned.

Specified by:

getUri in interface DatasetRepository

Overrides:

getUri in class org.kitesdk.data.spi.filesystem.FileSystemDatasetRepository

Returns:

the URI of this repository