org.apache.giraph.examples.scc

Class SccComputation

java.lang.Object

org.apache.giraph.conf.DefaultImmutableClassesGiraphConfigurable<I,V,E>

org.apache.giraph.worker.WorkerAggregatorDelegator<I,V,E>

org.apache.giraph.graph.AbstractComputation<I,V,E,M,M>

org.apache.giraph.graph.BasicComputation<org.apache.hadoop.io.LongWritable,SccVertexValue,org.apache.hadoop.io.NullWritable,org.apache.hadoop.io.LongWritable>

org.apache.giraph.examples.scc.SccComputation

All Implemented Interfaces:

AggregatorUsage, GiraphConfigurationSettable<org.apache.hadoop.io.LongWritable,SccVertexValue,org.apache.hadoop.io.NullWritable>, ImmutableClassesGiraphConfigurable<org.apache.hadoop.io.LongWritable,SccVertexValue,org.apache.hadoop.io.NullWritable>, TypesHolder<org.apache.hadoop.io.LongWritable,SccVertexValue,org.apache.hadoop.io.NullWritable,org.apache.hadoop.io.LongWritable,org.apache.hadoop.io.LongWritable>, Computation<org.apache.hadoop.io.LongWritable,SccVertexValue,org.apache.hadoop.io.NullWritable,org.apache.hadoop.io.LongWritable,org.apache.hadoop.io.LongWritable>, WorkerAggregatorUsage, WorkerBroadcastUsage, WorkerGlobalCommUsage, WorkerIndexUsage<org.apache.hadoop.io.LongWritable>, WorkerReduceUsage

public class SccComputation
extends BasicComputation<org.apache.hadoop.io.LongWritable,SccVertexValue,org.apache.hadoop.io.NullWritable,org.apache.hadoop.io.LongWritable>

Finds strongly connected components of the graph.

Constructor Summary

Constructors

Constructor and Description
SccComputation()

Method Summary

Modifier and Type	Method and Description
void	compute(Vertex<org.apache.hadoop.io.LongWritable,SccVertexValue,org.apache.hadoop.io.NullWritable> vertex, Iterable<org.apache.hadoop.io.LongWritable> messages) Must be defined by user to do computation on a single Vertex.
void	preSuperstep() Prepare for computation.

Methods inherited from class org.apache.giraph.graph.AbstractComputation

addEdgeRequest, addVertexRequest, addVertexRequest, getContext, getMyWorkerIndex, getSuperstep, getTotalNumEdges, getTotalNumVertices, getWorkerContext, getWorkerCount, getWorkerForVertex, initialize, postSuperstep, removeEdgesRequest, removeVertexRequest, sendMessage, sendMessageToAllEdges, sendMessageToMultipleEdges

Methods inherited from class org.apache.giraph.worker.WorkerAggregatorDelegator

aggregate, getAggregatedValue, getBroadcast, reduce, reduceMerge, setWorkerGlobalCommUsage

Methods inherited from class org.apache.giraph.conf.DefaultImmutableClassesGiraphConfigurable

getConf, setConf

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.giraph.conf.ImmutableClassesGiraphConfigurable

getConf

Methods inherited from interface org.apache.giraph.conf.GiraphConfigurationSettable

setConf

Methods inherited from interface org.apache.giraph.worker.WorkerBroadcastUsage

getBroadcast

Methods inherited from interface org.apache.giraph.worker.WorkerReduceUsage

reduce, reduceMerge

Methods inherited from interface org.apache.giraph.worker.WorkerAggregatorUsage

aggregate

Methods inherited from interface org.apache.giraph.aggregators.AggregatorUsage

getAggregatedValue

Constructor Detail

SccComputation

public SccComputation()

Method Detail

preSuperstep

public void preSuperstep()

Description copied from class: AbstractComputation

Prepare for computation. This method is executed exactly once prior to AbstractComputation.compute(Vertex, Iterable) being called for any of the vertices in the partition.

Specified by:

preSuperstep in interface Computation<org.apache.hadoop.io.LongWritable,SccVertexValue,org.apache.hadoop.io.NullWritable,org.apache.hadoop.io.LongWritable,org.apache.hadoop.io.LongWritable>

Overrides:

preSuperstep in class AbstractComputation<org.apache.hadoop.io.LongWritable,SccVertexValue,org.apache.hadoop.io.NullWritable,org.apache.hadoop.io.LongWritable,org.apache.hadoop.io.LongWritable>

compute

public void compute(Vertex<org.apache.hadoop.io.LongWritable,SccVertexValue,org.apache.hadoop.io.NullWritable> vertex,
                    Iterable<org.apache.hadoop.io.LongWritable> messages)
             throws IOException

Description copied from class: AbstractComputation

Must be defined by user to do computation on a single Vertex.

Specified by:

compute in interface Computation<org.apache.hadoop.io.LongWritable,SccVertexValue,org.apache.hadoop.io.NullWritable,org.apache.hadoop.io.LongWritable,org.apache.hadoop.io.LongWritable>

Specified by:

compute in class AbstractComputation<org.apache.hadoop.io.LongWritable,SccVertexValue,org.apache.hadoop.io.NullWritable,org.apache.hadoop.io.LongWritable,org.apache.hadoop.io.LongWritable>

Parameters:

vertex - Vertex

messages - Messages that were sent to this vertex in the previous superstep. Each message is only guaranteed to have a life expectancy as long as next() is not called.

Throws:

IOException