Package org.apache.flink.connector.datagen.functions

Class FromElementsGeneratorFunction<OUT>

java.lang.Object

org.apache.flink.connector.datagen.functions.FromElementsGeneratorFunction<OUT>

Type Parameters:

OUT - The type of elements returned by this function.

All Implemented Interfaces:

Serializable, Function, GeneratorFunction<Long,OUT>, OutputTypeConfigurable<OUT>

@Internal
public class FromElementsGeneratorFunction<OUT>
extends Object
implements GeneratorFunction<Long,OUT>, OutputTypeConfigurable<OUT>

A stream generator function that returns a sequence of elements.

This generator function serializes the elements using Flink's type information. That way, any object transport using Java serialization will not be affected by the serializability of the elements.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor	Description
FromElementsGeneratorFunction(TypeInformation<OUT> typeInfo, ExecutionConfig config, Iterable<OUT> elements)
FromElementsGeneratorFunction(TypeInformation<OUT> typeInfo, OUT... elements)

Method Summary

Modifier and Type	Method	Description
static <OUT> void	checkIterable(Iterable<OUT> elements, Class<?> viewedAs)	Verifies that all elements in the iterable are non-null, and are of the given class, or a subclass thereof.
TypeSerializer<OUT>	getSerializer()
OUT	map(Long nextIndex)
void	open(SourceReaderContext readerContext)	Initialization method for the function.
void	setOutputType(TypeInformation<OUT> outTypeInfo, ExecutionConfig executionConfig)	Is called by the org.apache.flink.streaming.api.graph.StreamGraph#addOperator(Integer, String, StreamOperator, TypeInformation, TypeInformation, String) method when the org.apache.flink.streaming.api.graph.StreamGraph is generated.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.flink.connector.datagen.source.GeneratorFunction

close

Constructor Detail

FromElementsGeneratorFunction

@SafeVarargs
public FromElementsGeneratorFunction(TypeInformation<OUT> typeInfo,
                                     OUT... elements)

FromElementsGeneratorFunction

public FromElementsGeneratorFunction(TypeInformation<OUT> typeInfo,
                                     ExecutionConfig config,
                                     Iterable<OUT> elements)

Method Detail

getSerializer

@VisibleForTesting
@Nullable
public TypeSerializer<OUT> getSerializer()

open

public void open(SourceReaderContext readerContext)
          throws Exception

Description copied from interface: GeneratorFunction

Initialization method for the function. It is called once before the actual data mapping methods.

Specified by:

open in interface GeneratorFunction<Long,OUT>

Throws:

Exception

map

public OUT map(Long nextIndex)
        throws Exception

Specified by:

map in interface GeneratorFunction<Long,OUT>

Throws:

Exception

setOutputType

public void setOutputType(TypeInformation<OUT> outTypeInfo,
                          ExecutionConfig executionConfig)

Description copied from interface: OutputTypeConfigurable

Is called by the org.apache.flink.streaming.api.graph.StreamGraph#addOperator(Integer, String, StreamOperator, TypeInformation, TypeInformation, String) method when the org.apache.flink.streaming.api.graph.StreamGraph is generated. The method is called with the output TypeInformation which is also used for the org.apache.flink.streaming.runtime.tasks.StreamTask output serializer.

Specified by:

setOutputType in interface OutputTypeConfigurable<OUT>

Parameters:

outTypeInfo - Output type information of the org.apache.flink.streaming.runtime.tasks.StreamTask

executionConfig - Execution configuration

checkIterable

public static <OUT> void checkIterable(Iterable<OUT> elements,
                                       Class<?> viewedAs)

Verifies that all elements in the iterable are non-null, and are of the given class, or a subclass thereof.

Type Parameters:

OUT - The generic type of the iterable to be checked.

Parameters:

elements - The iterable to check.

viewedAs - The class to which the elements must be assignable to.