org.apache.flink.api.java.functions

Class FirstReducer<T>

java.lang.Object

org.apache.flink.api.java.functions.FirstReducer<T>

Type Parameters:

T -

All Implemented Interfaces:

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

@Internal
public class FirstReducer<T>
extends Object
implements org.apache.flink.api.common.functions.GroupReduceFunction<T,T>, org.apache.flink.api.common.functions.GroupCombineFunction<T,T>

Reducer that only emits the first N elements in a group.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
FirstReducer(int n)

Method Summary

Modifier and Type	Method and Description
void	combine(Iterable<T> values, org.apache.flink.util.Collector<T> out)
void	reduce(Iterable<T> values, org.apache.flink.util.Collector<T> out)

Methods inherited from class java.lang.Object

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

Constructor Detail

FirstReducer

public FirstReducer(int n)

Method Detail

reduce

public void reduce(Iterable<T> values,
                   org.apache.flink.util.Collector<T> out)
            throws Exception

Specified by:

reduce in interface org.apache.flink.api.common.functions.GroupReduceFunction<T,T>

Throws:

Exception

combine

public void combine(Iterable<T> values,
                    org.apache.flink.util.Collector<T> out)
             throws Exception

Specified by:

combine in interface org.apache.flink.api.common.functions.GroupCombineFunction<T,T>

Throws:

Exception