org.apache.giraph.jython

Class JythonGiraphComputation<I extends org.apache.hadoop.io.WritableComparable,V extends org.apache.hadoop.io.Writable,E extends org.apache.hadoop.io.Writable,M1 extends org.apache.hadoop.io.Writable,M2 extends org.apache.hadoop.io.Writable>

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,M1,M2>

org.apache.giraph.jython.JythonGiraphComputation<I,V,E,M1,M2>

Type Parameters:

I - Vertex ID

V - Vertex value

E - Edge value

M1 - Incoming message value

M2 - Outgoing message value

All Implemented Interfaces:

AggregatorUsage, GiraphConfigurationSettable<I,V,E>, ImmutableClassesGiraphConfigurable<I,V,E>, TypesHolder<I,V,E,M1,M2>, Computation<I,V,E,M1,M2>, WorkerAggregatorUsage, WorkerBroadcastUsage, WorkerGlobalCommUsage, WorkerIndexUsage<I>, WorkerReduceUsage

public class JythonGiraphComputation<I extends org.apache.hadoop.io.WritableComparable,V extends org.apache.hadoop.io.Writable,E extends org.apache.hadoop.io.Writable,M1 extends org.apache.hadoop.io.Writable,M2 extends org.apache.hadoop.io.Writable>
extends AbstractComputation<I,V,E,M1,M2>

The Computation class for using Jython with Giraph. This class implements the Giraph necessary interfaces but it actually holds a reference to the JythonComputation which does the real work. The two classes are linked and together they allow us to coerce Jython types to Writables.

Constructor Summary

Constructors

Constructor and Description
JythonGiraphComputation(JythonComputation jythonComputation) Constructor

Method Summary

Modifier and Type	Method and Description
void	compute(Vertex<I,V,E> vertex, Iterable<M1> messages) Must be defined by user to do computation on a single Vertex.
org.apache.hadoop.io.WritableComparable	wrapIdIfNecessary(Object object) Wrap a vertex id in a WritableComparable wrapper if necessary
<W extends org.apache.hadoop.io.Writable> W	wrapIfNecessary(Object object, GraphType graphType) Wrap a user value (IVEMM) in a Writable wrapper if necessary

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

addEdgeRequest, addVertexRequest, addVertexRequest, getContext, getMyWorkerIndex, getSuperstep, getTotalNumEdges, getTotalNumVertices, getWorkerContext, getWorkerCount, getWorkerForVertex, initialize, postSuperstep, preSuperstep, 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

JythonGiraphComputation

public JythonGiraphComputation(JythonComputation jythonComputation)

Constructor

Parameters:

jythonComputation - the user's Jython computation

Method Detail

compute

public void compute(Vertex<I,V,E> vertex,
                    Iterable<M1> 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<I extends org.apache.hadoop.io.WritableComparable,V extends org.apache.hadoop.io.Writable,E extends org.apache.hadoop.io.Writable,M1 extends org.apache.hadoop.io.Writable,M2 extends org.apache.hadoop.io.Writable>

Specified by:

compute in class AbstractComputation<I extends org.apache.hadoop.io.WritableComparable,V extends org.apache.hadoop.io.Writable,E extends org.apache.hadoop.io.Writable,M1 extends org.apache.hadoop.io.Writable,M2 extends org.apache.hadoop.io.Writable>

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

wrapIdIfNecessary

public org.apache.hadoop.io.WritableComparable wrapIdIfNecessary(Object object)

Wrap a vertex id in a WritableComparable wrapper if necessary

Parameters:

object - data to wrap

Returns:

writable value

wrapIfNecessary

public <W extends org.apache.hadoop.io.Writable> W wrapIfNecessary(Object object,
                                                                   GraphType graphType)

Wrap a user value (IVEMM) in a Writable wrapper if necessary

Type Parameters:

W - writable type

Parameters:

object - data to wrap

graphType - type of data (IVEMM)

Returns:

writable value