EntryKey
- type of the original input keyKeyIn
- type of key used as input key typeValueIn
- type of value used as input value type@Beta public interface MappingJob<EntryKey,KeyIn,ValueIn>
This interface describes a mapping mapreduce Job.
For further information see Job
.
Job
Modifier and Type | Method and Description |
---|---|
MappingJob<EntryKey,KeyIn,ValueIn> |
chunkSize(int chunkSize)
Defines the number of elements per chunk.
|
<ValueOut> ReducingJob<EntryKey,KeyIn,ValueOut> |
combiner(CombinerFactory<? super KeyIn,? super ValueIn,? extends ValueOut> combinerFactory)
Defines the
CombinerFactory for this task. |
MappingJob<EntryKey,KeyIn,ValueIn> |
keyPredicate(KeyPredicate<? super EntryKey> predicate)
Defines the
KeyPredicate implementation to preselect keys that the MapReduce task will be executed on. |
MappingJob<EntryKey,KeyIn,ValueIn> |
onKeys(EntryKey... keys)
Defines keys to execute the mapper and a possibly defined reducer against.
|
MappingJob<EntryKey,KeyIn,ValueIn> |
onKeys(Iterable<? extends EntryKey> keys)
Defines keys to execute the mapper and a possibly defined reducer against.
|
<ValueOut> ReducingSubmittableJob<EntryKey,KeyIn,ValueOut> |
reducer(ReducerFactory<? super KeyIn,? super ValueIn,? extends ValueOut> reducerFactory)
Defines the
ReducerFactory for this task. |
JobCompletableFuture<Map<KeyIn,List<ValueIn>>> |
submit()
Submits the task to Hazelcast and executes the defined mapper and reducer on all cluster nodes.
|
<ValueOut> JobCompletableFuture<ValueOut> |
submit(Collator<Map.Entry<KeyIn,List<ValueIn>>,ValueOut> collator)
Submits the task to Hazelcast, executes the defined mapper and reducer on all cluster nodes, and executes the
collator before returning the final result.
|
MappingJob<EntryKey,KeyIn,ValueIn> |
topologyChangedStrategy(TopologyChangedStrategy topologyChangedStrategy)
Defines the strategy to handle topology changes while executing the map reduce job.
|
MappingJob<EntryKey,KeyIn,ValueIn> onKeys(Iterable<? extends EntryKey> keys)
keys
- keys to be executed againstMappingJob<EntryKey,KeyIn,ValueIn> onKeys(EntryKey... keys)
keys
- keys to be executed againstMappingJob<EntryKey,KeyIn,ValueIn> keyPredicate(KeyPredicate<? super EntryKey> predicate)
KeyPredicate
implementation to preselect keys that the MapReduce task will be executed on.
Preselecting keys can speed up the job massively.onKeys(Iterable)
or onKeys(Object...)
to define a
range of known and evaluated keys.predicate
- predicate implementation to be used to evaluate keysMappingJob<EntryKey,KeyIn,ValueIn> chunkSize(int chunkSize)
ReducerFactory
is defined, the chunk will be sent to the nodes that
are responsible for the emitted keys.chunkSize
- the number of elements per chunkMappingJob<EntryKey,KeyIn,ValueIn> topologyChangedStrategy(TopologyChangedStrategy topologyChangedStrategy)
TopologyChangedStrategy
.topologyChangedStrategy
- strategy to use<ValueOut> ReducingJob<EntryKey,KeyIn,ValueOut> combiner(CombinerFactory<? super KeyIn,? super ValueIn,? extends ValueOut> combinerFactory)
CombinerFactory
for this task. This method is not idempotent and is callable only one time.
Further calls result in an IllegalStateException
thrown telling you to not change the internal state.ValueOut
- type of the combined valuecombinerFactory
- CombinerFactory to build Combiner<ValueOut> ReducingSubmittableJob<EntryKey,KeyIn,ValueOut> reducer(ReducerFactory<? super KeyIn,? super ValueIn,? extends ValueOut> reducerFactory)
ReducerFactory
for this task. This method is not idempotent and is callable only one time.
Further calls result in an IllegalStateException
thrown telling you to not change the internal state.ValueOut
- type of the reduced valuereducerFactory
- ReducerFactory to build ReducersJobCompletableFuture<Map<KeyIn,List<ValueIn>>> submit()
<ValueOut> JobCompletableFuture<ValueOut> submit(Collator<Map.Entry<KeyIn,List<ValueIn>>,ValueOut> collator)
ValueOut
- type of the collated valuecollator
- collator to use after map and reduceCopyright © 2016 Hazelcast, Inc.. All Rights Reserved.