org.apache.giraph.graph

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

Type Parameters:

I - Vertex id

V - Vertex data

E - Edge data

All Superinterfaces:

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

All Known Implementing Classes:

ByteValueVertex, DefaultVertex, OnlyIdVertex

public interface Vertex<I extends org.apache.hadoop.io.WritableComparable,V extends org.apache.hadoop.io.Writable,E extends org.apache.hadoop.io.Writable>
extends ImmutableClassesGiraphConfigurable<I,V,E>

Class which holds vertex id, data and edges.

Method Summary

Modifier and Type	Method and Description
void	addEdge(Edge<I,E> edge) Add an edge for this vertex (happens immediately)
Iterable<E>	getAllEdgeValues(I targetVertexId) Get an iterable over the values of all edges with the given target vertex id.
Iterable<Edge<I,E>>	getEdges() Get a read-only view of the out-edges of this vertex.
E	getEdgeValue(I targetVertexId) Return the value of the first edge with the given target vertex id, or null if there is no such edge.
I	getId() Get the vertex id.
Iterable<MutableEdge<I,E>>	getMutableEdges() Get an iterable of out-edges that can be modified in-place.
int	getNumEdges() Get the number of outgoing edges on this vertex.
V	getValue() Get the vertex value (data stored with vertex)
void	initialize(I id, V value) Initialize id and value.
void	initialize(I id, V value, Iterable<Edge<I,E>> edges) Initialize id, value, and edges.
boolean	isHalted() Is this vertex done?
void	removeEdges(I targetVertexId) Removes all edges pointing to the given vertex id.
void	setEdges(Iterable<Edge<I,E>> edges) Set the outgoing edges for this vertex.
void	setEdgeValue(I targetVertexId, E edgeValue) If an edge to the target vertex exists, set it to the given edge value.
void	setValue(V value) Set the vertex data (immediately visible in the computation)
void	unwrapMutableEdges() If a MutableEdgesWrapper was used to provide a mutable iterator, copy any remaining edges to the new OutEdges data structure and keep a direct reference to it (thus discarding the wrapper).
void	voteToHalt() After this is called, the compute() code will no longer be called for this vertex unless a message is sent to it.
void	wakeUp() Re-activate vertex if halted.

Methods inherited from interface org.apache.giraph.conf.ImmutableClassesGiraphConfigurable

getConf

Methods inherited from interface org.apache.giraph.conf.GiraphConfigurationSettable

setConf

Method Detail

initialize

void initialize(I id,
                V value,
                Iterable<Edge<I,E>> edges)

Initialize id, value, and edges. This method (or the alternative form initialize(id, value)) must be called after instantiation, unless readFields() is called.

Parameters:

id - Vertex id

value - Vertex value

edges - Iterable of edges

initialize

void initialize(I id,
                V value)

Initialize id and value. Vertex edges will be empty. This method (or the alternative form initialize(id, value, edges)) must be called after instantiation, unless readFields() is called.

Parameters:

id - Vertex id

value - Vertex value

getId

I getId()

Get the vertex id.

Returns:

My vertex id.

getValue

V getValue()

Get the vertex value (data stored with vertex)

Returns:

Vertex value

setValue

void setValue(V value)

Set the vertex data (immediately visible in the computation)

Parameters:

value - Vertex data to be set

voteToHalt

void voteToHalt()

After this is called, the compute() code will no longer be called for this vertex unless a message is sent to it. Then the compute() code will be called once again until this function is called. The application finishes only when all vertices vote to halt.

getNumEdges

int getNumEdges()

Get the number of outgoing edges on this vertex.

Returns:

the total number of outbound edges from this vertex

getEdges

Iterable<Edge<I,E>> getEdges()

Get a read-only view of the out-edges of this vertex. Note: edge objects returned by this iterable may be invalidated as soon as the next element is requested. Thus, keeping a reference to an edge almost always leads to undesired behavior. Accessing the edges with other methods (e.g., addEdge()) during iteration leads to undefined behavior.

Returns:

the out edges (sort order determined by subclass implementation).

setEdges

void setEdges(Iterable<Edge<I,E>> edges)

Set the outgoing edges for this vertex.

Parameters:

edges - Iterable of edges

getMutableEdges

Iterable<MutableEdge<I,E>> getMutableEdges()

Get an iterable of out-edges that can be modified in-place. This can mean changing the current edge value or removing the current edge (by using the iterator version). Note: accessing the edges with other methods (e.g., addEdge()) during iteration leads to undefined behavior.

Returns:

An iterable of mutable out-edges

getEdgeValue

E getEdgeValue(I targetVertexId)

Return the value of the first edge with the given target vertex id, or null if there is no such edge. Note: edge value objects returned by this method may be invalidated by the next call. Thus, keeping a reference to an edge value almost always leads to undesired behavior.

Parameters:

targetVertexId - Target vertex id

Returns:

Edge value (or null if missing)

setEdgeValue

void setEdgeValue(I targetVertexId,
                  E edgeValue)

If an edge to the target vertex exists, set it to the given edge value. This only makes sense with strict graphs.

Parameters:

targetVertexId - Target vertex id

edgeValue - Edge value

getAllEdgeValues

Iterable<E> getAllEdgeValues(I targetVertexId)

Get an iterable over the values of all edges with the given target vertex id. This only makes sense for multigraphs (i.e. graphs with parallel edges). Note: edge value objects returned by this method may be invalidated as soon as the next element is requested. Thus, keeping a reference to an edge value almost always leads to undesired behavior.

Parameters:

targetVertexId - Target vertex id

Returns:

Iterable of edge values

addEdge

void addEdge(Edge<I,E> edge)

Add an edge for this vertex (happens immediately)

Parameters:

edge - Edge to add

removeEdges

void removeEdges(I targetVertexId)

Removes all edges pointing to the given vertex id.

Parameters:

targetVertexId - the target vertex id

unwrapMutableEdges

void unwrapMutableEdges()

If a MutableEdgesWrapper was used to provide a mutable iterator, copy any remaining edges to the new OutEdges data structure and keep a direct reference to it (thus discarding the wrapper). Called by the Giraph infrastructure after computation.

wakeUp

void wakeUp()

Re-activate vertex if halted.

isHalted

boolean isHalted()

Is this vertex done?

Returns:

True if halted, false otherwise.