org.apache.giraph.io.formats

Class TextVertexInputFormat.TextVertexReaderFromEachLineProcessedHandlingExceptions<T,X extends Throwable>

java.lang.Object

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

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

org.apache.giraph.io.VertexReader<I,V,E>

org.apache.giraph.io.formats.TextVertexInputFormat.TextVertexReader

org.apache.giraph.io.formats.TextVertexInputFormat.TextVertexReaderFromEachLineProcessedHandlingExceptions<T,X>

Type Parameters:

T - The resulting type of preprocessing.

X - The exception type that can be thrown due to preprocessing.

All Implemented Interfaces:

AggregatorUsage, GiraphConfigurationSettable<I,V,E>, ImmutableClassesGiraphConfigurable<I,V,E>, WorkerAggregatorUsage, WorkerBroadcastUsage, WorkerGlobalCommUsage, WorkerReduceUsage

Enclosing class:

TextVertexInputFormat<I extends org.apache.hadoop.io.WritableComparable,V extends org.apache.hadoop.io.Writable,E extends org.apache.hadoop.io.Writable>

protected abstract class TextVertexInputFormat.TextVertexReaderFromEachLineProcessedHandlingExceptions<T,X extends Throwable>
extends TextVertexInputFormat.TextVertexReader

Abstract class to be implemented by the user to read a vertex from each text line after preprocessing it with exception handling.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	TextVertexReaderFromEachLineProcessedHandlingExceptions()

Method Summary

Modifier and Type	Method and Description
Vertex<I,V,E>	getCurrentVertex() Get the current vertex.
protected abstract Iterable<Edge<I,E>>	getEdges(T line) Reads edges from the preprocessed line.
protected abstract I	getId(T line) Reads vertex id from the preprocessed line.
protected abstract V	getValue(T line) Reads vertex value from the preprocessed line.
protected Vertex<I,V,E>	handleException(org.apache.hadoop.io.Text line, T processed, X e) Handles exceptions while reading vertex from each line.
boolean	nextVertex()
protected abstract T	preprocessLine(org.apache.hadoop.io.Text line) Preprocess the line so other methods can easily read necessary information for creating vertex.

Methods inherited from class org.apache.giraph.io.formats.TextVertexInputFormat.TextVertexReader

close, createLineRecordReader, getContext, getProgress, getRecordReader, initialize

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

TextVertexReaderFromEachLineProcessedHandlingExceptions

protected TextVertexReaderFromEachLineProcessedHandlingExceptions()

Method Detail

nextVertex

public final boolean nextVertex()
                         throws IOException,
                                InterruptedException

Specified by:

nextVertex in class VertexReader<I extends org.apache.hadoop.io.WritableComparable,V extends org.apache.hadoop.io.Writable,E extends org.apache.hadoop.io.Writable>

Returns:

false iff there are no more vertices

Throws:

IOException

InterruptedException

getCurrentVertex

public final Vertex<I,V,E> getCurrentVertex()
                                     throws IOException,
                                            InterruptedException

Description copied from class: VertexReader

Get the current vertex.

Specified by:

getCurrentVertex in class VertexReader<I extends org.apache.hadoop.io.WritableComparable,V extends org.apache.hadoop.io.Writable,E extends org.apache.hadoop.io.Writable>

Returns:

the current vertex which has been read. nextVertex() should be called first.

Throws:

IOException

InterruptedException

preprocessLine

protected abstract T preprocessLine(org.apache.hadoop.io.Text line)
                             throws X extends Throwable,
                                    IOException

Preprocess the line so other methods can easily read necessary information for creating vertex.

Parameters:

line - the current line to be read

Returns:

the preprocessed object

Throws:

X - exception that can be thrown while preprocessing the line

IOException - exception that can be thrown while reading

X extends Throwable

getId

protected abstract I getId(T line)
                    throws X extends Throwable,
                           IOException

Reads vertex id from the preprocessed line.

Parameters:

line - the object obtained by preprocessing the line

Returns:

the vertex id

Throws:

X - exception that can be thrown while reading the preprocessed object

IOException - exception that can be thrown while reading

X extends Throwable

getValue

protected abstract V getValue(T line)
                       throws X extends Throwable,
                              IOException

Reads vertex value from the preprocessed line.

Parameters:

line - the object obtained by preprocessing the line

Returns:

the vertex value

Throws:

X - exception that can be thrown while reading the preprocessed object

IOException - exception that can be thrown while reading

X extends Throwable

getEdges

protected abstract Iterable<Edge<I,E>> getEdges(T line)
                                         throws X extends Throwable,
                                                IOException

Reads edges from the preprocessed line.

Parameters:

line - the object obtained by preprocessing the line

Returns:

the edges

Throws:

X - exception that can be thrown while reading the preprocessed object

IOException - exception that can be thrown while reading

X extends Throwable

handleException

protected Vertex<I,V,E> handleException(org.apache.hadoop.io.Text line,
                                        T processed,
                                        X e)

Handles exceptions while reading vertex from each line.

Parameters:

line - the line that was being read when the exception was thrown

processed - the object obtained by preprocessing the line. Can be null if exception was thrown during preprocessing.

e - the exception thrown while reading the line

Returns:

the recovered/alternative vertex to be used