Class DOTImporter<V,​E>

  • Type Parameters:
    V - the graph vertex type
    E - the graph edge type
    All Implemented Interfaces:
    GraphImporter<V,​E>

    public class DOTImporter<V,​E>
    extends BaseEventDrivenImporter<V,​E>
    implements GraphImporter<V,​E>
    Import a graph from a DOT file.

    For a description of the format see http://en.wikipedia.org/wiki/DOT_language and http://www.graphviz.org/doc/info/lang.html

    The provided graph object, where the imported graph will be stored, must be able to support the features of the graph that is read. For example if the file contains self-loops then the graph provided must also support self-loops. The same for multiple edges. Whether edges are directed or not depends on the underlying implementation of the user provided graph object.

    The graph vertices and edges are build using the corresponding graph suppliers. The id of the vertices in the original dot file are reported as a vertex attribute named "ID". Thus, in case vertices in the dot file also contain an "ID" attribute, such an attribute will be reported multiple times.

    The default behavior of the importer is to use the graph vertex supplier in order to create vertices. The user can also bypass vertex creation by providing a custom vertex factory method using setVertexFactory(Function). The factory method is responsible to create a new graph vertex given the vertex identifier read from file.

    Author:
    Dimitrios Michail
    • Field Detail

      • DEFAULT_VERTEX_ID_KEY

        public static final java.lang.String DEFAULT_VERTEX_ID_KEY
        Default key used for vertex ID.
        See Also:
        Constant Field Values
    • Constructor Detail

      • DOTImporter

        public DOTImporter()
        Constructs a new importer.
    • Method Detail

      • importGraph

        public void importGraph​(Graph<V,​E> graph,
                                java.io.Reader input)
        Description copied from interface: GraphImporter
        Import a graph using the given Reader.

        It is the callers responsibility to ensure the Reader is closed after this method returned.

        Specified by:
        importGraph in interface GraphImporter<V,​E>
        Parameters:
        graph - the graph
        input - the input reader
      • getVertexFactory

        public java.util.function.Function<java.lang.String,​V> getVertexFactory()
        Get the user custom vertex factory. This is null by default and the graph supplier is used instead.
        Returns:
        the user custom vertex factory
      • setVertexFactory

        public void setVertexFactory​(java.util.function.Function<java.lang.String,​V> vertexFactory)
        Set the user custom vertex factory. The default behavior is being null in which case the graph vertex supplier is used. If supplied the vertex factory is called every time a new vertex is encountered in the file. The method is called with parameter the vertex identifier from the file and should return the actual graph vertex to add to the graph.
        Parameters:
        vertexFactory - a vertex factory