org.apache.giraph.examples.scc

Class SccVertexValue

java.lang.Object

org.apache.giraph.examples.scc.SccVertexValue

All Implemented Interfaces:

org.apache.hadoop.io.Writable

public class SccVertexValue
extends Object
implements org.apache.hadoop.io.Writable

Vertex value for the Strongly Connected Components algorithm. It keeps track of the parents of the vertex in order to traverse the graph backwards.

Constructor Summary

Constructors

Constructor and Description
SccVertexValue() Public constructor required for serialization.
SccVertexValue(long value) Constructor

Method Summary

Modifier and Type	Method and Description
void	addParent(long vertexId) Adds a vertex id to the list of parent vertices.
void	clearParents() Clear parents list.
void	deactivate() Remove this vertex from the computation.
long	get() Returns the vertex value.
it.unimi.dsi.fastutil.longs.LongArrayList	getParents() Returns the list of parent vertices, i.e., vertices that are at the other end of incoming edges.
boolean	isActive() Indicates whether the vertex was removed in a Trimming phase.
void	readFields(DataInput in)
void	set(long value) Sets the vertex value.
String	toString()
void	write(DataOutput out)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

SccVertexValue

public SccVertexValue()

Public constructor required for serialization.

SccVertexValue

public SccVertexValue(long value)

Constructor

Parameters:

value - Initial value for this vertex.

Method Detail

readFields

public void readFields(DataInput in)
                throws IOException

Specified by:

readFields in interface org.apache.hadoop.io.Writable

Throws:

IOException

write

public void write(DataOutput out)
           throws IOException

Specified by:

write in interface org.apache.hadoop.io.Writable

Throws:

IOException

getParents

public it.unimi.dsi.fastutil.longs.LongArrayList getParents()

Returns the list of parent vertices, i.e., vertices that are at the other end of incoming edges. If the vertex doesn't have any incoming edge, it returns null.

Returns:

List of the vertex's parents.

addParent

public void addParent(long vertexId)

Adds a vertex id to the list of parent vertices.

Parameters:

vertexId - It of the parent vertex.

clearParents

public void clearParents()

Clear parents list.

set

public void set(long value)

Sets the vertex value. At the end of the SCC computation, vertices with the same vertex value are part of the same component.

Parameters:

value - Vertex value.

get

public long get()

Returns the vertex value. At the end of the SCC computation, vertices with the same vertex value are part of the same component.

Returns:

Current vertex value.

deactivate

public void deactivate()

Remove this vertex from the computation.

isActive

public boolean isActive()

Indicates whether the vertex was removed in a Trimming phase.

Returns:

True if the vertex was trimmed, otherwise, return false.

toString

public String toString()

Overrides:

toString in class Object