Package com.jgalgo.gen

Class CompleteGraphGenerator<V,​E>

  • Type Parameters:
    V - the vertices type
    E - the edges type
    All Implemented Interfaces:
    GraphGenerator<V,​E>
    public class CompleteGraphGenerator<V,​E>
extends Object
implements GraphGenerator<V,​E>
    Generates a complete graph.

    A complete graph is a graph in which each pair of graph vertices is connected by an edge. If the graph is directed, then there are two edges between two pair of vertices, one in each direction. Self edges are optional, but are disabled by default. Parallel edges are never created.

    In the following example, a complete graph with 10 vertices is generated: 

     
 Graph<Integer, Integer> g = new CompleteGraphGenerator<>(IntGraphFactory.undirected())
 		.directed(false)
 		.vertices(10)
 		.edges(IdBuilderInt.defaultBuilder())
 		.selfEdges(false)
 		.generate();
    Author:
    Barak Ugav

    • Constructor Detail

      • CompleteGraphGenerator

        public CompleteGraphGenerator()
        Create a new complete graph generator that will use the default graph factory.

        The default graph factory does not have vertex builder, so if only the number of vertices is set using vertices(int), the vertex builder must be set explicitly using graphFactory().setVertexBuilder(...). Same holds for edges, for which the number of them is determine by the number of vertices, whether or not the graph is directed and whether or not self edges are generated. Alternatively, the methods vertices(int, IdBuilder) and edges(IdBuilder) can be used to set the number of vertices and provide a vertex/edge builder that will override the (maybe non existing) vertex/edge builder of the graph factory. The vertex set can also be set explicitly using vertices(Collection).

      • CompleteGraphGenerator

        public CompleteGraphGenerator​(GraphFactory<V,​E> factory)
        Create a new complete graph generator that will use the given graph factory.

        If the factory has a vertex builder it will be used to generate the vertices of the generated graph(s) if only the number of vertices is set using vertices(int). If the factory has an edge builder it will be used to generate the edges of the generated graph(s) if it will not be overridden by edges(IdBuilder).

        During the graph(s) generation, the method GraphFactory.setDirected(boolean) of the given factory will be called to align the created graph with the generator configuration. If self edges are generated (see selfEdges(boolean)), the method GraphFactory.allowSelfEdges() will also be called.

        To generate int graphs, pass an instance of IntGraphFactory to this constructor.

        Parameters:
        factory - the graph factory that will be used to create the generated graph(s)

    • Method Detail

      • graphFactory

        public GraphFactory<V,​E> graphFactory()
        Get the graph factory that will be used to create the generated graph(s).

        It's possible to customize the factory before generating the graph(s), for example by using GraphFactory.addHint(GraphFactory.Hint) to optimize the generated graph(s) for a specific algorithm. If the factory has a vertex builder it will be used to generate the vertices of the generated graph(s) if only the number of vertices is set using vertices(int). If the factory has an edge builder it will be used to generate the edges of the generated graph(s) if it will not be overridden by edges(IdBuilder).

        During the graph(s) generation, the method GraphFactory.setDirected(boolean) of the given factory will be called to align the created graph with the generator configuration. If self edges are generated (see selfEdges(boolean)), the method GraphFactory.allowSelfEdges() will also be called.

        Returns:
        the graph factory that will be used to create the generated graph(s)

      • vertices

        public CompleteGraphGenerator<V,​E> vertices​(int verticesNum)
        Set the number of vertices that will be generated for each graph.

        The vertices will be generated using the vertex builder of the graph factory, see GraphFactory.setVertexBuilder(IdBuilder). The default graph factory does not have a vertex builder, so it must be set explicitly, or IntGraphFactory, which does have such builder, should be passed in the constructor. Another alternative is to use vertices(int, IdBuilder) which set the number of vertices and provide a vertex builder that will override the (maybe non existing) vertex builder of the graph factory. The generation will happen independently for each graph generated. If there is no vertex builder, an exception will be thrown during generation. This method override all previous calls to any of vertices(Collection), vertices(int) or vertices(int, IdBuilder).

        Parameters:
        verticesNum - the number of vertices that will be generated for each graph
        Returns:
        this generator
        Throws:
        IllegalArgumentException - if verticesNum is negative

      • vertices

        public CompleteGraphGenerator<V,​E> vertices​(int verticesNum,
                                                  IdBuilder<V> vertexBuilder)
        Set the number of vertices that will be generated for each graph, and the vertex builder that will be used to generate them.

        The vertices will be generated using the provided vertex builder, and the vertex generator provided by the graph factory (if exists) will be ignored. The generation will happen independently for each graph generated. This method override all previous calls to any of vertices(Collection), vertices(int) or vertices(int, IdBuilder).

        Parameters:
        verticesNum - the number of vertices that will be generated for each graph
        vertexBuilder - the vertex builder, or null to use the vertex builder of the graph factory
        Returns:
        this generator
        Throws:
        IllegalArgumentException - if verticesNum is negative

      • edges

        public CompleteGraphGenerator<V,​E> edges​(IdBuilder<E> edgeBuilder)
        Set the edge builder that will be used to generate edges.

        The edges will be generated using the provided edge builder, and the edge generator provided by the graph factory (if exists) will be ignored. The generation will happen independently for each graph generated. If this method is not called, or called with a null argument, the edge builder of the graph factory will be used. If the graph factory does not have an edge builder, an exception will be thrown during generation.

        Parameters:
        edgeBuilder - the edge builder, or null to use the edge builder of the graph factory
        Returns:
        this generator

      • directed

        public CompleteGraphGenerator<V,​E> directed​(boolean directed)
        Determine if the generated graph(s) is directed or undirected.

        By default, the generated graph(s) is undirected.

        Parameters:
        directed - true if the generated graph(s) will be directed, false if undirected
        Returns:
        this generator

      • selfEdges

        public CompleteGraphGenerator<V,​E> selfEdges​(boolean selfEdges)
        Determine if the generated graph(s) will contain self-edges.

        Self edges are edges with the same source and target vertex. By default, the generated graph(s) will not contain self-edges.

        Parameters:
        selfEdges - true if the generated graph(s) will contain self-edges, false otherwise
        Returns:
        this generator

      • generateIntoBuilder

        public GraphBuilder<V,​E> generateIntoBuilder()
        Description copied from interface: GraphGenerator
        Generates a graph into a builder.

        This is the a more flexible way to generate a graph. The builder can be used to generate a mutable or immutable graph, or to add additional vertices or edges on top of the generated ones.

        Specified by:
        generateIntoBuilder in interface GraphGenerator<V,​E>
        Returns:
        a new graph builder populated by the generator with the generator parameters