public class ClusterCountMapReduce extends StaticMapReduce<MapReduce.NullObject,Serializable,MapReduce.NullObject,Integer,Integer>
| Modifier and Type | Class and Description |
|---|---|
static class |
ClusterCountMapReduce.Builder |
MapReduce.MapEmitter<K,V>, MapReduce.NullObject, MapReduce.ReduceEmitter<OK,OV>, MapReduce.Stage| Modifier and Type | Field and Description |
|---|---|
static String |
CLUSTER_COUNT_MEMORY_KEY |
static String |
DEFAULT_MEMORY_KEY |
MAP_REDUCE| Modifier and Type | Method and Description |
|---|---|
static ClusterCountMapReduce.Builder |
build() |
void |
combine(MapReduce.NullObject key,
Iterator<Serializable> values,
MapReduce.ReduceEmitter<MapReduce.NullObject,Integer> emitter)
The combine() method is logically executed at all "machines" in parallel.
|
boolean |
doStage(MapReduce.Stage stage)
A MapReduce job can be map-only, map-reduce-only, or map-combine-reduce.
|
Integer |
generateFinalResult(Iterator<KeyValue<MapReduce.NullObject,Integer>> keyValues)
The key/value pairs emitted by reduce() (or map() in a map-only job) can be iterated to generate a local JVM Java object.
|
String |
getMemoryKey()
The results of the MapReduce job are associated with a memory-key to ultimately be stored in
Memory. |
void |
loadState(Graph graph,
Configuration configuration)
When it is necessary to load the state of a MapReduce job, this method is called.
|
void |
map(Vertex vertex,
MapReduce.MapEmitter<MapReduce.NullObject,Serializable> emitter)
The map() method is logically executed at all vertices in the graph in parallel.
|
void |
reduce(MapReduce.NullObject key,
Iterator<Serializable> values,
MapReduce.ReduceEmitter<MapReduce.NullObject,Integer> emitter)
The reduce() method is logically on the "machine" the respective key hashes to.
|
void |
storeState(Configuration configuration)
When it is necessary to store the state of a MapReduce job, this method is called.
|
String |
toString() |
clone, equals, hashCodefinalize, getClass, notify, notifyAll, wait, wait, waitaddResultToMemory, createMapReduce, getMapKeySort, getReduceKeySort, workerEnd, workerStartpublic static final String CLUSTER_COUNT_MEMORY_KEY
public static final String DEFAULT_MEMORY_KEY
public void storeState(Configuration configuration)
MapReducestoreState in interface MapReduce<MapReduce.NullObject,Serializable,MapReduce.NullObject,Integer,Integer>storeState in class StaticMapReduce<MapReduce.NullObject,Serializable,MapReduce.NullObject,Integer,Integer>configuration - the configuration to store the state of the MapReduce job in.public void loadState(Graph graph, Configuration configuration)
MapReducegraph - the graph the MapReduce job will run againstconfiguration - the configuration to load the state of the MapReduce job from.public boolean doStage(MapReduce.Stage stage)
MapReducestage - the stage to check for definition.public void map(Vertex vertex, MapReduce.MapEmitter<MapReduce.NullObject,Serializable> emitter)
MapReducevertex - the current vertex being map() processed.emitter - the component that allows for key/value pairs to be emitted to the next stage.public void combine(MapReduce.NullObject key, Iterator<Serializable> values, MapReduce.ReduceEmitter<MapReduce.NullObject,Integer> emitter)
MapReducekey - the key that has aggregated valuesvalues - the aggregated values associated with the keyemitter - the component that allows for key/value pairs to be emitted to the reduce stage.public void reduce(MapReduce.NullObject key, Iterator<Serializable> values, MapReduce.ReduceEmitter<MapReduce.NullObject,Integer> emitter)
MapReducekey - the key that has aggregated valuesvalues - the aggregated values associated with the keyemitter - the component that allows for key/value pairs to be emitted as the final result.public Integer generateFinalResult(Iterator<KeyValue<MapReduce.NullObject,Integer>> keyValues)
MapReducekeyValues - the key/value pairs that were emitted from reduce() (or map() in a map-only job)public String getMemoryKey()
MapReduceMemory.public String toString()
toString in class StaticMapReduce<MapReduce.NullObject,Serializable,MapReduce.NullObject,Integer,Integer>public static ClusterCountMapReduce.Builder build()
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