org.apache.beam.sdk.coders

Class ListCoder<T>

java.lang.Object

org.apache.beam.sdk.coders.StandardCoder<IterableT>

org.apache.beam.sdk.coders.IterableLikeCoder<T,List<T>>

org.apache.beam.sdk.coders.ListCoder<T>

Type Parameters:

T - the type of the elements of the Lists being transcoded

All Implemented Interfaces:

Serializable, Coder<List<T>>

public class ListCoder<T>
extends IterableLikeCoder<T,List<T>>

A Coder for List, using the format of IterableLikeCoder.

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.beam.sdk.coders.Coder

Coder.Context, Coder.NonDeterministicException

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	ListCoder(Coder<T> elemCoder)

Method Summary

Modifier and Type	Method and Description
protected List<T>	decodeToIterable(List<T> decodedElements) Builds an instance of IterableT, this coder's associated Iterable-like subtype, from a list of decoded elements.
static <T> List<Object>	getInstanceComponents(List<T> exampleValue) Returns the first element in this list if it is non-empty, otherwise returns null.
static <T> ListCoder<T>	of(Coder<T> elemCoder)
static ListCoder<?>	of(List<Coder<?>> components)
void	verifyDeterministic() List sizes are always known, so ListIterable may be deterministic while the general IterableLikeCoder is not.

Methods inherited from class org.apache.beam.sdk.coders.IterableLikeCoder

decode, encode, getCoderArguments, getElemCoder, getInstanceComponentsHelper, isRegisterByteSizeObserverCheap, registerByteSizeObserver

Methods inherited from class org.apache.beam.sdk.coders.StandardCoder

asCloudObject, consistentWithEquals, equals, getAllowedEncodings, getComponents, getEncodedElementByteSize, getEncodingId, hashCode, structuralValue, toString, verifyDeterministic, verifyDeterministic

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

ListCoder

protected ListCoder(Coder<T> elemCoder)

Method Detail

of

public static <T> ListCoder<T> of(Coder<T> elemCoder)

decodeToIterable

protected final List<T> decodeToIterable(List<T> decodedElements)

Description copied from class: IterableLikeCoder

Builds an instance of IterableT, this coder's associated Iterable-like subtype, from a list of decoded elements.

Specified by:

decodeToIterable in class IterableLikeCoder<T,List<T>>

of

public static ListCoder<?> of(List<Coder<?>> components)

getInstanceComponents

public static <T> List<Object> getInstanceComponents(List<T> exampleValue)

Returns the first element in this list if it is non-empty, otherwise returns null.

verifyDeterministic

public void verifyDeterministic()
                         throws Coder.NonDeterministicException

List sizes are always known, so ListIterable may be deterministic while the general IterableLikeCoder is not.

Specified by:

verifyDeterministic in interface Coder<List<T>>

Overrides:

verifyDeterministic in class IterableLikeCoder<T,List<T>>

Throws:

Coder.NonDeterministicException - if this coder is not deterministic.