Package org.apache.beam.sdk.transforms.join

Class CoGbkResult

java.lang.Object

org.apache.beam.sdk.transforms.join.CoGbkResult

public class CoGbkResult
extends Object

A row result of a CoGroupByKey. This is a tuple of Iterables produced for a given key, and these can be accessed in different ways.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	CoGbkResult.CoGbkResultCoder	A Coder for CoGbkResults.

Constructor Summary

Constructors

Constructor	Description
CoGbkResult(CoGbkResultSchema schema, Iterable<RawUnionValue> taggedValues)	A row in the PCollection resulting from a CoGroupByKey transform.
CoGbkResult(CoGbkResultSchema schema, Iterable<RawUnionValue> taggedValues, int inMemoryElementCount, int minElementsPerTag)

Method Summary

Modifier and Type	Method	Description
<V> CoGbkResult	and(TupleTag<V> tag, List<V> data)	Returns a new CoGbkResult based on this, with the given tag and given data added to it.
static CoGbkResult	empty()	Returns an empty CoGbkResult.
<V> Iterable<V>	getAll(String tag)	Like getAll(TupleTag) but using a String instead of a TupleTag.
<V> Iterable<V>	getAll(TupleTag<V> tag)	Returns the values from the table represented by the given TupleTag<V> as an Iterable<V> (which may be empty if there are no results).
<V> V	getOnly(String tag)	Like getOnly(TupleTag) but using a String instead of a TupleTag.
<V> @Nullable V	getOnly(String tag, @Nullable V defaultValue)	Like getOnly(TupleTag, Object) but using a String instead of a TupleTag.
<V> V	getOnly(TupleTag<V> tag)	If there is a singleton value for the given tag, returns it.
<V> @Nullable V	getOnly(TupleTag<V> tag, @Nullable V defaultValue)	If there is a singleton value for the given tag, returns it.
CoGbkResultSchema	getSchema()	Returns the schema used by this CoGbkResult.
boolean	isEmpty()
static <V> CoGbkResult	of(TupleTag<V> tag, List<V> data)	Returns a new CoGbkResult that contains just the given tag and given data.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Details

CoGbkResult

public CoGbkResult(CoGbkResultSchema schema,
 Iterable<RawUnionValue> taggedValues)

A row in the PCollection resulting from a CoGroupByKey transform. Currently, this row must fit into memory.

Parameters:

schema - the set of tuple tags used to refer to input tables and result values

taggedValues - the raw results from a group-by-key

CoGbkResult

public CoGbkResult(CoGbkResultSchema schema,
 Iterable<RawUnionValue> taggedValues,
 int inMemoryElementCount,
 int minElementsPerTag)

Method Details

isEmpty

public boolean isEmpty()

getSchema

public CoGbkResultSchema getSchema()

Returns the schema used by this CoGbkResult.

toString

public String toString()

Overrides:

toString in class Object

getAll

public <V> Iterable<V> getAll(TupleTag<V> tag)

Returns the values from the table represented by the given TupleTag<V> as an Iterable<V> (which may be empty if there are no results).

If tag was not part of the original CoGroupByKey, throws an IllegalArgumentException.

getAll

public <V> Iterable<V> getAll(String tag)

Like getAll(TupleTag) but using a String instead of a TupleTag.

getOnly

public <V> V getOnly(TupleTag<V> tag)

If there is a singleton value for the given tag, returns it. Otherwise, throws an IllegalArgumentException.

If tag was not part of the original CoGroupByKey, throws an IllegalArgumentException.

getOnly

public <V> V getOnly(String tag)

Like getOnly(TupleTag) but using a String instead of a TupleTag.

getOnly

public <V> @Nullable V getOnly(TupleTag<V> tag,
 @Nullable V defaultValue)

If there is a singleton value for the given tag, returns it. If there is no value for the given tag, returns the defaultValue.

If tag was not part of the original CoGroupByKey, throws an IllegalArgumentException.

getOnly

public <V> @Nullable V getOnly(String tag,
 @Nullable V defaultValue)

Like getOnly(TupleTag, Object) but using a String instead of a TupleTag.

of

public static <V> CoGbkResult of(TupleTag<V> tag,
 List<V> data)

Returns a new CoGbkResult that contains just the given tag and given data.

and

public <V> CoGbkResult and(TupleTag<V> tag,
 List<V> data)

Returns a new CoGbkResult based on this, with the given tag and given data added to it.

empty

public static CoGbkResult empty()

Returns an empty CoGbkResult.