com.hazelcast.mapreduce

Interface KeyPredicate<Key>

Type Parameters:

Key - key type

All Superinterfaces:

Serializable

Deprecated.

MapReduce is deprecated and will be removed in 4.0. For map aggregations, you can use Aggregator on IMap. For general data processing, it is superseded by Hazelcast Jet.

@Deprecated
public interface KeyPredicate<Key>
extends Serializable

This interface is used to pre-evaluate keys before spreading the MapReduce task to the cluster. Pre-selecting keys can speed up the job since not all partitions may be used.

Since:

3.2

Method Summary

Modifier and Type	Method and Description
boolean	evaluate(Key key) Deprecated. This method evaluates whether or not to select a key.

Method Detail

evaluate

boolean evaluate(Key key)

Deprecated.

This method evaluates whether or not to select a key.

Parameters:

key - The key to evaluate

Returns:

true if the MapReduce task should be executed on this key, false otherwise