org.apache.flink.streaming.api.functions.source

Class FromElementsFunction<T>

java.lang.Object

org.apache.flink.streaming.api.functions.source.FromElementsFunction<T>

All Implemented Interfaces:

Serializable, org.apache.flink.api.common.functions.Function, SourceFunction<T>

public class FromElementsFunction<T>
extends Object
implements SourceFunction<T>

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.flink.streaming.api.functions.source.SourceFunction

SourceFunction.SourceContext<T>

Constructor Summary

Constructors

Constructor and Description
FromElementsFunction(Collection<T> elements)
FromElementsFunction(Iterable<T> elements)
FromElementsFunction(T... elements)

Method Summary

Modifier and Type	Method and Description
void	cancel() Cancels the source.
void	run(SourceFunction.SourceContext<T> ctx) Starts the source.

Methods inherited from class java.lang.Object

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

Constructor Detail

FromElementsFunction

public FromElementsFunction(T... elements)

FromElementsFunction

public FromElementsFunction(Collection<T> elements)

FromElementsFunction

public FromElementsFunction(Iterable<T> elements)

Method Detail

run

public void run(SourceFunction.SourceContext<T> ctx)
         throws Exception

Description copied from interface: SourceFunction

Starts the source. You can use the Collector parameter to emit elements. Sources that implement Checkpointed must lock on the checkpoint lock (using a synchronized block) before updating internal state and/or emitting elements. Also, the update of state and emission of elements must happen in the same synchronized block.

Specified by:

run in interface SourceFunction<T>

Parameters:

ctx - The context for interaction with the outside world.

Throws:

Exception

cancel

public void cancel()

Description copied from interface: SourceFunction

Cancels the source. Most sources will have a while loop inside the SourceFunction.run(org.apache.flink.streaming.api.functions.source.SourceFunction.SourceContext<T>) method. You need to ensure that the source will break out of this loop. This can be achieved by having a volatile field "isRunning" that is checked in the loop and that is set to false in this method.

Specified by:

cancel in interface SourceFunction<T>