org.kitesdk.data
Interface View<E>

Type Parameters:

E - The type of entities stored in the Dataset underlying this View.

All Known Subinterfaces:

Dataset<E>, RandomAccessDataset<E>, RefineableView<E>

@Immutable
public interface View<E>

A View is a subset of a Dataset. A View defines a space of potential storage keys, or a partition space. Views can be created from ranges, partial keys, or the union of other views.

Since:

0.9.0

Method Summary

Dataset<E>	getDataset() Returns the underlying Dataset that this is a View of.
boolean	includes(E entity) Returns whether an entity Object would be included in this View if it were present in the Dataset.
DatasetReader<E>	newReader() Get an appropriate DatasetReader implementation based on this View of the underlying Dataset implementation.
DatasetWriter<E>	newWriter() Get an appropriate DatasetWriter implementation based on this View of the underlying Dataset implementation.

Method Detail

getDataset

Dataset<E> getDataset()

Returns the underlying Dataset that this is a View of.

Returns:

the underlying Dataset

newReader

DatasetReader<E> newReader()

Get an appropriate DatasetReader implementation based on this View of the underlying Dataset implementation. Implementations are free to return different types of readers depending on the disposition of the data. For example, a partitioned dataset may use a different reader than that of a non-partitioned dataset. Clients should not make any assumptions about the returned implementations. Implementations are free to change them at any time.

Throws:

DatasetException

newWriter

DatasetWriter<E> newWriter()

Get an appropriate DatasetWriter implementation based on this View of the underlying Dataset implementation. Implementations are free to return different types of writers depending on the disposition of the data. For example, a partitioned dataset may use a different writer than that of a non-partitioned dataset. Clients should not make any assumptions about the returned implementations. Implementations are free to change them at any time.

Throws:

DatasetException

includes

boolean includes(E entity)

Returns whether an entity Object would be included in this View if it were present in the Dataset.

Parameters:

entity - an entity Object

Returns:

true if entity is in the partition space of this view.

Since:

0.11.0