org.apache.giraph.io.gora

Class GoraEdgeOutputFormat.GoraEdgeWriter

java.lang.Object

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

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

org.apache.giraph.io.gora.GoraEdgeOutputFormat.GoraEdgeWriter

All Implemented Interfaces:

GiraphConfigurationSettable<I,V,E>, ImmutableClassesGiraphConfigurable<I,V,E>

Direct Known Subclasses:

GoraGEdgeEdgeOutputFormat.GoraGEdgeEdgeWriter

Enclosing class:

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

protected abstract class GoraEdgeOutputFormat.GoraEdgeWriter
extends EdgeWriter<I,V,E>

Abstract class to be implemented by the user based on their specific vertex/edges output.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	GoraEdgeWriter()

Method Summary

Modifier and Type	Method and Description
void	close(org.apache.hadoop.mapreduce.TaskAttemptContext context) Close this EdgeWriter to future operations.
protected abstract org.apache.gora.persistency.Persistent	getGoraEdge(I srcId, V srcValue, Edge<I,E> edge) Each edge needs to be transformed into a Gora object to be sent to a specific data store.
protected abstract Object	getGoraKey(I srcId, V srcValue, Edge<I,E> edge) Gets the correct key from a computed vertex.
void	initialize(org.apache.hadoop.mapreduce.TaskAttemptContext context) Use the context to setup writing the edges.
void	writeEdge(I srcId, V srcValue, Edge<I,E> edge) Writes the next vertex and associated data

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

GoraEdgeWriter

protected GoraEdgeWriter()

Method Detail

initialize

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

Description copied from class: EdgeWriter

Use the context to setup writing the edges. Guaranteed to be called prior to any other function.

Specified by:

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

Parameters:

context - Context used to write the vertices.

Throws:

IOException

InterruptedException

close

public void close(org.apache.hadoop.mapreduce.TaskAttemptContext context)
           throws IOException,
                  InterruptedException

Description copied from class: EdgeWriter

Close this EdgeWriter to future operations.

Specified by:

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

Parameters:

context - the context of the task

Throws:

IOException

InterruptedException

writeEdge

public void writeEdge(I srcId,
                      V srcValue,
                      Edge<I,E> edge)
               throws IOException,
                      InterruptedException

Description copied from class: EdgeWriter

Writes the next vertex and associated data

Specified by:

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

Parameters:

srcId - the vertex ID from which the edge originates

srcValue - the vertex value; the vertex is the one from which the edge originates

edge - edge to be written

Throws:

IOException

InterruptedException

getGoraEdge

protected abstract org.apache.gora.persistency.Persistent getGoraEdge(I srcId,
                                                                      V srcValue,
                                                                      Edge<I,E> edge)

Each edge needs to be transformed into a Gora object to be sent to a specific data store.

Parameters:

edge - edge to be transformed into a Gora object

srcId - source vertex id

srcValue - source vertex value

Returns:

Gora representation of the vertex

getGoraKey

protected abstract Object getGoraKey(I srcId,
                                     V srcValue,
                                     Edge<I,E> edge)

Gets the correct key from a computed vertex.

Parameters:

edge - edge to extract the key from.

srcId - source vertex id

srcValue - source vertex value

Returns:

The key representing such edge.