Modifier and Type | Class and Description |
---|---|
static class |
PageRankMapReduce.Builder |
MapReduce.MapEmitter<K,V>, MapReduce.NullObject, MapReduce.ReduceEmitter<OK,OV>, MapReduce.Stage
Modifier and Type | Field and Description |
---|---|
static String |
DEFAULT_MEMORY_KEY |
static String |
PAGE_RANK_MEMORY_KEY |
MAP_REDUCE
Modifier and Type | Method and Description |
---|---|
static PageRankMapReduce.Builder |
build() |
boolean |
doStage(MapReduce.Stage stage)
A MapReduce job can be map-only, map-reduce-only, or map-combine-reduce.
|
Iterator<KeyValue<Object,Double>> |
generateFinalResult(Iterator<KeyValue<Object,Double>> 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(Configuration configuration)
When it is necessary to load the state of a MapReduce job, this method is called.
|
void |
map(Vertex vertex,
MapReduce.MapEmitter<Object,Double> emitter)
The map() method is logically executed at all vertices in the graph in parallel.
|
void |
storeState(Configuration configuration)
When it is necessary to store the state of a MapReduce job, this method is called.
|
String |
toString() |
clone, equals, hashCode
finalize, getClass, notify, notifyAll, wait, wait, wait
addResultToMemory, combine, createMapReduce, getMapKeySort, getReduceKeySort, reduce, workerEnd, workerStart
public static final String PAGE_RANK_MEMORY_KEY
public static final String DEFAULT_MEMORY_KEY
public void storeState(Configuration configuration)
MapReduce
storeState
in interface MapReduce<Object,Double,Object,Double,Iterator<KeyValue<Object,Double>>>
storeState
in class StaticMapReduce<Object,Double,Object,Double,Iterator<KeyValue<Object,Double>>>
configuration
- the configuration to store the state of the MapReduce job in.public void loadState(Configuration configuration)
MapReduce
It is important that the state loaded from loadState() is identical to any state created from a constructor. For those GraphComputers that do not need to use Configurations to migrate state between JVMs, the constructor will only be used.
configuration
- the configuration to load the state of the MapReduce job from.public boolean doStage(MapReduce.Stage stage)
MapReduce
stage
- the stage to check for definition.public void map(Vertex vertex, MapReduce.MapEmitter<Object,Double> emitter)
MapReduce
vertex
- the current vertex being map() processed.emitter
- the component that allows for key/value pairs to be emitted to the next stage.public Iterator<KeyValue<Object,Double>> generateFinalResult(Iterator<KeyValue<Object,Double>> keyValues)
MapReduce
keyValues
- the key/value pairs that were emitted from reduce() (or map() in a map-only job)public String getMemoryKey()
MapReduce
Memory
.public String toString()
public static PageRankMapReduce.Builder build()
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