Package it.unimi.dsi.webgraph.examples

Class IntegerTriplesArcLabelledImmutableGraph

java.lang.Object

it.unimi.dsi.webgraph.ImmutableGraph

it.unimi.dsi.webgraph.labelling.ArcLabelledImmutableGraph

it.unimi.dsi.webgraph.labelling.ArcLabelledImmutableSequentialGraph

it.unimi.dsi.webgraph.examples.IntegerTriplesArcLabelledImmutableGraph

All Implemented Interfaces:

FlyweightPrototype<ImmutableGraph>

public class IntegerTriplesArcLabelledImmutableGraph
extends ArcLabelledImmutableSequentialGraph

A class exposing a list of triples as an ArcLabelledImmutableGraph. The triples are interpreted as labelled arcs: the first element is the source, the second element is the target, and the third element must be a nonnegative integer that will be saved using a GammaCodedIntLabel.

This class is mainly a useful example of how to expose of your data via an ArcLabelledImmutableGraph, and it is also used to build test cases, but it is not efficient or particularly refined.

A main method reads from standard input a list of TAB-separated triples and writes the corresponding graph using BVGraph and BitStreamArcLabelledImmutableGraph.

Nested Class Summary

Nested classes/interfaces inherited from class it.unimi.dsi.webgraph.ImmutableGraph

ImmutableGraph.LoadMethod

Field Summary

Fields inherited from class it.unimi.dsi.webgraph.labelling.ArcLabelledImmutableGraph

UNDERLYINGGRAPH_PROPERTY_KEY, UNDERLYINGGRAPH_SUFFIX

Fields inherited from class it.unimi.dsi.webgraph.ImmutableGraph

GRAPHCLASS_PROPERTY_KEY, NUMBER_OF_THREADS_PROPERTY, PROPERTIES_EXTENSION

Constructor Summary

Constructors

Constructor	Description
IntegerTriplesArcLabelledImmutableGraph(int[][] triple)	Creates a new arc-labelled immutable graph using a specified list of triples.

Method Summary

Modifier and Type	Method	Description
boolean	hasCopiableIterators()	Whether the node iterators returned by this graph support NodeIterator.copy(int).
static void	main(String[] arg)
ArcLabelledNodeIterator	nodeIterator()	Returns a node iterator for scanning the graph sequentially, starting from the first node.
ArcLabelledNodeIterator	nodeIterator(int from)	Throws an UnsupportedOperationException.
int	numNodes()	Returns the number of nodes of this graph.
Label	prototype()	Returns a prototype of the labels used by this graph.
ArcLabelledNodeIterator.LabelledArcIterator	successors(int from)	Throws an UnsupportedOperationException.

Methods inherited from class it.unimi.dsi.webgraph.labelling.ArcLabelledImmutableSequentialGraph

copy, labelArray, outdegree, randomAccess, successorArray

Methods inherited from class it.unimi.dsi.webgraph.labelling.ArcLabelledImmutableGraph

equals, load, load, loadOffline, loadOffline, loadOnce, loadSequential, loadSequential, toString

Methods inherited from class it.unimi.dsi.webgraph.ImmutableGraph

basename, hashCode, load, loadMapped, loadMapped, numArcs, outdegrees, splitNodeIterators, store, store

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Details

IntegerTriplesArcLabelledImmutableGraph

public IntegerTriplesArcLabelledImmutableGraph(int[][] triple)

Creates a new arc-labelled immutable graph using a specified list of triples.

Note that it is impossible to specify isolated nodes with indices larger than the largest node with positive indegree or outdegree, as the number of nodes is computed by maximising over all indices in triple.

Parameters:

triple - a list of triples specifying labelled arcs (see the class documentation); order is not relevant, but multiple arcs are not allowed.

Method Details

prototype

public Label prototype()

Description copied from class: ArcLabelledImmutableGraph

Returns a prototype of the labels used by this graph. The prototype can be used to produce new copies, but must not be modified by the caller.

Specified by:

prototype in class ArcLabelledImmutableGraph

Returns:

a prototype for the labels of this graph.

numNodes

public int numNodes()

Description copied from class: ImmutableGraph

Returns the number of nodes of this graph.

Albeit this method is not optional, it is allowed that this method throws an UnsupportedOperationException if this graph has never been entirely traversed using a node iterator. This apparently bizarre behaviour is necessary to support implementations as ArcListASCIIGraph, which do not know the actual number of nodes until a traversal has been completed.

Specified by:

numNodes in class ImmutableGraph

Returns:

the number of nodes.

hasCopiableIterators

public boolean hasCopiableIterators()

Description copied from class: ImmutableGraph

Whether the node iterators returned by this graph support NodeIterator.copy(int).

Overrides:

hasCopiableIterators in class ImmutableGraph

Returns:

true if this graph provides copiable iterators.

nodeIterator

public ArcLabelledNodeIterator nodeIterator(int from)

Description copied from class: ArcLabelledImmutableSequentialGraph

Throws an UnsupportedOperationException.

Overrides:

nodeIterator in class ArcLabelledImmutableSequentialGraph

Parameters:

from - the node from which the iterator will iterate.

Returns:

an ArcLabelledNodeIterator for accessing nodes, successors and their labels sequentially.

See Also:

ImmutableGraph.nodeIterator()

successors

public ArcLabelledNodeIterator.LabelledArcIterator successors(int from)

Description copied from class: ArcLabelledImmutableSequentialGraph

Throws an UnsupportedOperationException.

Overrides:

successors in class ArcLabelledImmutableSequentialGraph

Parameters:

from - a node.

Returns:

a lazy iterator over the successors of the node.

nodeIterator

public ArcLabelledNodeIterator nodeIterator()

Description copied from class: ImmutableGraph

Returns a node iterator for scanning the graph sequentially, starting from the first node.

Overrides:

nodeIterator in class ArcLabelledImmutableGraph

Returns:

a NodeIterator for accessing nodes and successors sequentially.

main

public static void main(String[] arg)
                 throws JSAPException,
IOException

Throws:

JSAPException

IOException