co.cask.cdap.data2.datafabric.dataset

Class AbstractDatasetProvider

java.lang.Object

co.cask.cdap.data2.datafabric.dataset.AbstractDatasetProvider

All Implemented Interfaces:

DatasetProvider

public abstract class AbstractDatasetProvider
extends Object
implements DatasetProvider

Provides Dataset instances using methods implemented by subclasses. Used by RemoteDatasetFramework and DatasetInstanceService. Use this when you want to control how dataset instances are created. For example, when you want to obtain a Dataset instance without having to make remote calls.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractDatasetProvider(DatasetDefinitionRegistryFactory registryFactory)

Method Summary

Methods

Modifier and Type	Method and Description
abstract void	createIfNotExists(Id.DatasetInstance instance, String type, co.cask.cdap.api.dataset.DatasetProperties creationProps) Creates the dataset if it doesn't already exist.
<T extends co.cask.cdap.api.dataset.Dataset> T	get(Id.DatasetInstance instance, ClassLoader classLoader, Map<String,String> arguments) Gets a dataset.
<T extends co.cask.cdap.api.dataset.Dataset> T	get(Id.DatasetInstance instance, DatasetTypeMeta typeMeta, co.cask.cdap.api.dataset.DatasetSpecification spec, DatasetClassLoaderProvider classLoaderProvider, ClassLoader classLoader, Map<String,String> arguments)
abstract DatasetMeta	getMeta(Id.DatasetInstance instance) Gets the DatasetMeta for a dataset.
<T extends co.cask.cdap.api.dataset.Dataset> T	getOrCreate(Id.DatasetInstance instance, String type, co.cask.cdap.api.dataset.DatasetProperties creationProps, ClassLoader classLoader, Map<String,String> arguments) Gets a dataset, and creates it first if it doesn't yet exist.
<T extends DatasetType> T	getType(DatasetTypeMeta implementationInfo, ClassLoader classLoader, DatasetClassLoaderProvider classLoaderProvider) Return an instance of the DatasetType corresponding to given dataset modules.

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractDatasetProvider

protected AbstractDatasetProvider(DatasetDefinitionRegistryFactory registryFactory)

Method Detail

getMeta

@Nullable
public abstract DatasetMeta getMeta(Id.DatasetInstance instance)
                             throws Exception

Gets the DatasetMeta for a dataset.

Parameters:

instance - the dataset

Returns:

the DatasetMeta

Throws:

Exception

createIfNotExists

public abstract void createIfNotExists(Id.DatasetInstance instance,
                     String type,
                     co.cask.cdap.api.dataset.DatasetProperties creationProps)
                                throws Exception

Creates the dataset if it doesn't already exist.

Parameters:

instance - the dataset

type - the type of dataset to create

creationProps - creation properties

Throws:

Exception

getOrCreate

public <T extends co.cask.cdap.api.dataset.Dataset> T getOrCreate(Id.DatasetInstance instance,
                                                         String type,
                                                         co.cask.cdap.api.dataset.DatasetProperties creationProps,
                                                         @Nullable
                                                         ClassLoader classLoader,
                                                         @Nullable
                                                         Map<String,String> arguments)
                                                       throws Exception

Description copied from interface: DatasetProvider

Gets a dataset, and creates it first if it doesn't yet exist.

Specified by:

getOrCreate in interface DatasetProvider

Type Parameters:

T - the type of dataset

Parameters:

instance - the dataset ID

type - the type of dataset

creationProps - the creation properties

classLoader - the classloader to use

arguments - the runtime arguments for the dataset

Returns:

the dataset

Throws:

Exception

get

public <T extends co.cask.cdap.api.dataset.Dataset> T get(Id.DatasetInstance instance,
                                                 @Nullable
                                                 ClassLoader classLoader,
                                                 @Nullable
                                                 Map<String,String> arguments)
                                               throws Exception

Description copied from interface: DatasetProvider

Gets a dataset.

Specified by:

get in interface DatasetProvider

Type Parameters:

T - the type of dataset

Parameters:

instance - the dataset ID

classLoader - the classloader to use

arguments - the runtime arguments for the dataset

Returns:

the dataset

Throws:

Exception

get

public <T extends co.cask.cdap.api.dataset.Dataset> T get(Id.DatasetInstance instance,
                                                 DatasetTypeMeta typeMeta,
                                                 co.cask.cdap.api.dataset.DatasetSpecification spec,
                                                 DatasetClassLoaderProvider classLoaderProvider,
                                                 @Nullable
                                                 ClassLoader classLoader,
                                                 @Nullable
                                                 Map<String,String> arguments)
                                               throws IOException

Throws:

IOException

getType

public <T extends DatasetType> T getType(DatasetTypeMeta implementationInfo,
                                ClassLoader classLoader,
                                DatasetClassLoaderProvider classLoaderProvider)

Return an instance of the DatasetType corresponding to given dataset modules. Uses the given classloader as a parent for all dataset modules, and the given classloader provider to get classloaders for each dataset module in given the dataset type meta. Order of dataset modules in the given DatasetTypeMeta is important. The classloader for the first dataset module is used as the parent of the second dataset module and so on until the last dataset module. The classloader for the last dataset module is then used as the classloader for the returned DatasetType.

Type Parameters:

T - the type of DatasetType

Parameters:

implementationInfo - the dataset type metadata to instantiate the type from

classLoader - the parent classloader to use for dataset modules

classLoaderProvider - the classloader provider to get classloaders for each dataset module

Returns:

an instance of the DatasetType