org.apache.giraph.io

Class ReverseEdgeDuplicator<I extends org.apache.hadoop.io.WritableComparable,E extends org.apache.hadoop.io.Writable>

java.lang.Object

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

org.apache.giraph.worker.WorkerAggregatorDelegator<I,org.apache.hadoop.io.Writable,E>

org.apache.giraph.io.EdgeReader<I,E>

org.apache.giraph.io.ReverseEdgeDuplicator<I,E>

Type Parameters:

I - Vertex id

E - Edge Value

All Implemented Interfaces:

AggregatorUsage, GiraphConfigurationSettable<I,org.apache.hadoop.io.Writable,E>, ImmutableClassesGiraphConfigurable<I,org.apache.hadoop.io.Writable,E>, WorkerAggregatorUsage, WorkerBroadcastUsage, WorkerGlobalCommUsage, WorkerReduceUsage

public class ReverseEdgeDuplicator<I extends org.apache.hadoop.io.WritableComparable,E extends org.apache.hadoop.io.Writable>
extends EdgeReader<I,E>

An EdgeReader that creates the opposite direction edge for each edge read. Used to create an undirected graph from a directed input. This class is a decorator around any other EdgeReader.

Constructor Summary

Constructors

Constructor and Description
ReverseEdgeDuplicator(EdgeReader<I,E> baseReader) Constructor

Method Summary

Modifier and Type	Method and Description
void	close() Close this EdgeReader to future operations.
EdgeReader<I,E>	getBaseReader() Get wrapped EdgeReader
Edge<I,E>	getCurrentEdge() Get the current edge.
I	getCurrentSourceId() Get the current edge source id.
float	getProgress() How much of the input has the EdgeReader consumed i.e.
void	initialize(org.apache.hadoop.mapreduce.InputSplit inputSplit, org.apache.hadoop.mapreduce.TaskAttemptContext context) Use the input split and context to setup reading the edges.
boolean	nextEdge() Read the next edge.

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

Constructor Detail

ReverseEdgeDuplicator

public ReverseEdgeDuplicator(EdgeReader<I,E> baseReader)

Constructor

Parameters:

baseReader - EdgeReader to wrap

Method Detail

getBaseReader

public EdgeReader<I,E> getBaseReader()

Get wrapped EdgeReader

Returns:

EdgeReader

initialize

public void initialize(org.apache.hadoop.mapreduce.InputSplit inputSplit,
                       org.apache.hadoop.mapreduce.TaskAttemptContext context)
                throws IOException,
                       InterruptedException

Description copied from class: EdgeReader

Use the input split and context to setup reading the edges. Guaranteed to be called prior to any other function.

Specified by:

initialize in class EdgeReader<I extends org.apache.hadoop.io.WritableComparable,E extends org.apache.hadoop.io.Writable>

Parameters:

inputSplit - Input split to be used for reading edges.

context - Context from the task.

Throws:

IOException

InterruptedException

nextEdge

public boolean nextEdge()
                 throws IOException,
                        InterruptedException

Description copied from class: EdgeReader

Read the next edge.

Specified by:

nextEdge in class EdgeReader<I extends org.apache.hadoop.io.WritableComparable,E extends org.apache.hadoop.io.Writable>

Returns:

false iff there are no more edges

Throws:

IOException

InterruptedException

getCurrentSourceId

public I getCurrentSourceId()
                     throws IOException,
                            InterruptedException

Description copied from class: EdgeReader

Get the current edge source id.

Specified by:

getCurrentSourceId in class EdgeReader<I extends org.apache.hadoop.io.WritableComparable,E extends org.apache.hadoop.io.Writable>

Returns:

Current edge source id which has been read. nextEdge() should be called first.

Throws:

IOException

InterruptedException

getCurrentEdge

public Edge<I,E> getCurrentEdge()
                         throws IOException,
                                InterruptedException

Description copied from class: EdgeReader

Get the current edge.

Specified by:

getCurrentEdge in class EdgeReader<I extends org.apache.hadoop.io.WritableComparable,E extends org.apache.hadoop.io.Writable>

Returns:

the current edge which has been read. nextEdge() should be called first.

Throws:

IOException

InterruptedException

close

public void close()
           throws IOException

Description copied from class: EdgeReader

Close this EdgeReader to future operations.

Specified by:

close in class EdgeReader<I extends org.apache.hadoop.io.WritableComparable,E extends org.apache.hadoop.io.Writable>

Throws:

IOException

getProgress

public float getProgress()
                  throws IOException,
                         InterruptedException

Description copied from class: EdgeReader

How much of the input has the EdgeReader consumed i.e. has been processed by?

Specified by:

getProgress in class EdgeReader<I extends org.apache.hadoop.io.WritableComparable,E extends org.apache.hadoop.io.Writable>

Returns:

Progress from 0.0 to 1.0.

Throws:

IOException

InterruptedException