org.apache.giraph.io

Class EdgeReader<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>

Type Parameters:

I - Vertex id

E - Edge data

All Implemented Interfaces:

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

Direct Known Subclasses:

EdgeReaderWrapper, GeneratedEdgeReader, ReverseEdgeDuplicator, TextEdgeInputFormat.TextEdgeReader, WrappedEdgeReader

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

Analogous to org.apache.giraph.bsp.BspRecordReader for edges. Will read the edges from an input split.

Constructor Summary

Constructors

Constructor and Description
EdgeReader()

Method Summary

Modifier and Type	Method and Description
abstract void	close() Close this EdgeReader to future operations.
abstract Edge<I,E>	getCurrentEdge() Get the current edge.
abstract I	getCurrentSourceId() Get the current edge source id.
abstract float	getProgress() How much of the input has the EdgeReader consumed i.e.
abstract 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.
abstract 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

EdgeReader

public EdgeReader()

Method Detail

initialize

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

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

Parameters:

inputSplit - Input split to be used for reading edges.

context - Context from the task.

Throws:

IOException

InterruptedException

nextEdge

public abstract boolean nextEdge()
                          throws IOException,
                                 InterruptedException

Read the next edge.

Returns:

false iff there are no more edges

Throws:

IOException

InterruptedException

getCurrentSourceId

public abstract I getCurrentSourceId()
                              throws IOException,
                                     InterruptedException

Get the current edge source id.

Returns:

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

Throws:

IOException

InterruptedException

getCurrentEdge

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

Get the current edge.

Returns:

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

Throws:

IOException

InterruptedException

close

public abstract void close()
                    throws IOException

Close this EdgeReader to future operations.

Throws:

IOException

getProgress

public abstract float getProgress()
                           throws IOException,
                                  InterruptedException

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

Returns:

Progress from 0.0 to 1.0.

Throws:

IOException

InterruptedException