org.apache.flink.api.java.functions

Class FlatMapIterator<IN,OUT>

java.lang.Object

org.apache.flink.api.common.functions.AbstractRichFunction

org.apache.flink.api.common.functions.RichFlatMapFunction<IN,OUT>

org.apache.flink.api.java.functions.FlatMapIterator<IN,OUT>

Type Parameters:

IN - Type of the input elements.

OUT - Type of the returned elements.

All Implemented Interfaces:

Serializable, FlatMapFunction<IN,OUT>, Function, RichFunction

public abstract class FlatMapIterator<IN,OUT>
extends RichFlatMapFunction<IN,OUT>

A convenience variant of the RichFlatMapFunction that returns elements through an iterator, rather then through a collector. In all other respects, it behaves exactly like the FlatMapFunction.

The function needs to be serializable, as defined in Serializable.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
FlatMapIterator()

Method Summary

Methods

Modifier and Type	Method and Description
abstract Iterator<OUT>	flatMap(IN value) The core method of the function.
void	flatMap(IN value, Collector<OUT> out) Delegates calls to the flatMap(Object) method.

Methods inherited from class org.apache.flink.api.common.functions.AbstractRichFunction

close, getIterationRuntimeContext, getRuntimeContext, open, setRuntimeContext

Methods inherited from class java.lang.Object

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

Constructor Detail

FlatMapIterator

public FlatMapIterator()

Method Detail

flatMap

public abstract Iterator<OUT> flatMap(IN value)
                               throws Exception

The core method of the function. Takes an element from the input data set and transforms it into zero, one, or more elements.

Parameters:

value - The input value.

Returns:

An iterator over the returned elements.

Throws:

Exception - This method may throw exceptions. Throwing an exception will cause the operation to fail and may trigger recovery.

flatMap

public final void flatMap(IN value,
           Collector<OUT> out)
                   throws Exception

Delegates calls to the flatMap(Object) method.

Specified by:

flatMap in interface FlatMapFunction<IN,OUT>

Specified by:

flatMap in class RichFlatMapFunction<IN,OUT>

Throws:

Exception