org.apache.giraph.io

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

java.lang.Object

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

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

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

Type Parameters:

I - Vertex id

V - Vertex value

E - Edge value

All Implemented Interfaces:

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

Direct Known Subclasses:

GeneratedVertexInputFormat, InMemoryVertexInputFormat, MultiVertexInputFormat, PseudoRandomIntNullVertexInputFormat, PseudoRandomVertexInputFormat, SequenceFileVertexInputFormat, TextVertexInputFormat, VertexValueInputFormat, WattsStrogatzVertexInputFormat, WrappedVertexInputFormat

public abstract class VertexInputFormat<I extends org.apache.hadoop.io.WritableComparable,V extends org.apache.hadoop.io.Writable,E extends org.apache.hadoop.io.Writable>
extends GiraphInputFormat<I,V,E>

Use this to load data for a BSP application. Note that the InputSplit must also implement Writable. The InputSplits will determine the partitioning of vertices across the mappers, so keep that in consideration when implementing getSplits(). Provides access to ImmutableClassesGiraphConfiguration. It's guaranteed that whatever parameters are set in the configuration are also going to be available in all method arguments related to this input format (context in getSplits and createVertexReader; methods invoked on VertexReader). So if backing input format relies on some parameters from configuration, you can safely set them for example in DefaultImmutableClassesGiraphConfigurable.setConf(org.apache.giraph.conf.ImmutableClassesGiraphConfiguration).

Constructor Summary

Constructors

Constructor and Description
VertexInputFormat()

Method Summary

Modifier and Type	Method and Description
abstract VertexReader<I,V,E>	createVertexReader(org.apache.hadoop.mapreduce.InputSplit split, org.apache.hadoop.mapreduce.TaskAttemptContext context) Create a vertex reader for a given split.

Methods inherited from class org.apache.giraph.io.GiraphInputFormat

checkInputSpecs, getSplits, readInputSplit, writeInputSplit

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

VertexInputFormat

public VertexInputFormat()

Method Detail

createVertexReader

public abstract VertexReader<I,V,E> createVertexReader(org.apache.hadoop.mapreduce.InputSplit split,
                                                       org.apache.hadoop.mapreduce.TaskAttemptContext context)
                                                throws IOException

Create a vertex reader for a given split. Guaranteed to have been configured with setConf() prior to use. The framework will also call VertexReader.initialize(InputSplit, TaskAttemptContext) before the split is used.

Parameters:

split - the split to be read

context - the information about the task

Returns:

a new record reader

Throws:

IOException