Module org.jgrapht.core
Package org.jgrapht.graph.specifics

Class UndirectedSpecifics<V,E>

java.lang.Object
org.jgrapht.graph.specifics.UndirectedSpecifics<V,E>
Type Parameters:
V - the graph vertex type
E - the graph edge type
All Implemented Interfaces:
Serializable, Specifics<V,E>
Direct Known Subclasses:
FastLookupUndirectedSpecifics
public class UndirectedSpecifics<V,E> extends Object implements Specifics<V,E>, Serializable
Plain implementation of UndirectedSpecifics. This implementation requires the least amount of memory, at the expense of slow edge retrievals. Methods which depend on edge retrievals, e.g. getEdge(V u, V v), containsEdge(V u, V v), addEdge(V u, V v), etc may be relatively slow when the average degree of a vertex is high (dense graphs). For a fast implementation, use FastLookupUndirectedSpecifics.
Author:
Barak Naveh, Joris Kinable
See Also:

  • Field Details

  • Constructor Details

    • UndirectedSpecifics

      public UndirectedSpecifics(Graph<V,E> graph, Map<V,UndirectedEdgeContainer<V,E>> vertexMap, EdgeSetFactory<V,E> edgeSetFactory)
      Construct a new undirected specifics.
      Parameters:
      graph - the graph for which these specifics are for
      vertexMap - map for the storage of vertex edge sets. Needs to have a predictable iteration order.
      edgeSetFactory - factory for the creation of vertex edge sets

  • Method Details

    • addVertex

      public boolean addVertex(V v)
      Adds a vertex.
      Specified by:
      addVertex in interface Specifics<V,E>
      Parameters:
      v - vertex to be added.
      Returns:
      true if the vertex was added, false if the vertex was already present

    • getVertexSet

      public Set<V> getVertexSet()
      Get the vertex set.
      Specified by:
      getVertexSet in interface Specifics<V,E>
      Returns:
      the vertex set

    • getAllEdges

      public Set<E> getAllEdges(V sourceVertex, V targetVertex)
      Returns a set of all edges connecting source vertex to target vertex if such vertices exist in this graph. If any of the vertices does not exist or is null, returns null. If both vertices exist but no edges found, returns an empty set.
      Specified by:
      getAllEdges in interface Specifics<V,E>
      Parameters:
      sourceVertex - source vertex of the edge.
      targetVertex - target vertex of the edge.
      Returns:
      a set of all edges connecting source vertex to target vertex.

    • getEdge

      public E getEdge(V sourceVertex, V targetVertex)
      Returns an edge connecting source vertex to target vertex if such vertices and such edge exist in this graph. Otherwise returns null. If any of the specified vertices is null returns null

      In undirected graphs, the returned edge may have its source and target vertices in the opposite order.

      Specified by:
      getEdge in interface Specifics<V,E>
      Parameters:
      sourceVertex - source vertex of the edge.
      targetVertex - target vertex of the edge.
      Returns:
      an edge connecting source vertex to target vertex.

    • addEdgeToTouchingVertices

      public boolean addEdgeToTouchingVertices(V sourceVertex, V targetVertex, E e)
      Description copied from interface: Specifics
      Adds the specified edge to the edge containers of its source and target vertices.
      Specified by:
      addEdgeToTouchingVertices in interface Specifics<V,E>
      Parameters:
      sourceVertex - the source vertex
      targetVertex - the target vertex
      e - the edge
      Returns:
      true if the edge was added, false otherwise

    • addEdgeToTouchingVerticesIfAbsent

      public boolean addEdgeToTouchingVerticesIfAbsent(V sourceVertex, V targetVertex, E e)
      Description copied from interface: Specifics
      Adds the specified edge to the edge containers of its source and target vertices only if the edge is not already in the graph.
      Specified by:
      addEdgeToTouchingVerticesIfAbsent in interface Specifics<V,E>
      Parameters:
      sourceVertex - the source vertex
      targetVertex - the target vertex
      e - the edge
      Returns:
      true if the edge was added, false otherwise

    • createEdgeToTouchingVerticesIfAbsent

      public E createEdgeToTouchingVerticesIfAbsent(V sourceVertex, V targetVertex, Supplier<E> edgeSupplier)
      Description copied from interface: Specifics
      Creates an edge given an edge supplier and adds it to the edge containers of its source and target vertices only if the graph does not contain other edges with the same source and target vertices.
      Specified by:
      createEdgeToTouchingVerticesIfAbsent in interface Specifics<V,E>
      Parameters:
      sourceVertex - the source vertex
      targetVertex - the target vertex
      edgeSupplier - the function which will create the edge
      Returns:
      the newly created edge or null if an edge with the same source and target vertices was already present

    • degreeOf

      public int degreeOf(V vertex)
      Returns the degree of the specified vertex. A degree of a vertex in an undirected graph is the number of edges touching that vertex.
      Specified by:
      degreeOf in interface Specifics<V,E>
      Parameters:
      vertex - vertex whose degree is to be calculated.
      Returns:
      the degree of the specified vertex.

    • edgesOf

      public Set<E> edgesOf(V vertex)
      Returns a set of all edges touching the specified vertex. If no edges are touching the specified vertex returns an empty set.
      Specified by:
      edgesOf in interface Specifics<V,E>
      Parameters:
      vertex - the vertex for which a set of touching edges is to be returned.
      Returns:
      a set of all edges touching the specified vertex.

    • inDegreeOf

      public int inDegreeOf(V vertex)
      Returns the "in degree" of the specified vertex.
      Specified by:
      inDegreeOf in interface Specifics<V,E>
      Parameters:
      vertex - vertex whose in degree is to be calculated.
      Returns:
      the in degree of the specified vertex.

    • incomingEdgesOf

      public Set<E> incomingEdgesOf(V vertex)
      Returns a set of all edges incoming into the specified vertex.
      Specified by:
      incomingEdgesOf in interface Specifics<V,E>
      Parameters:
      vertex - the vertex for which the list of incoming edges to be returned.
      Returns:
      a set of all edges incoming into the specified vertex.

    • outDegreeOf

      public int outDegreeOf(V vertex)
      Returns the "out degree" of the specified vertex.
      Specified by:
      outDegreeOf in interface Specifics<V,E>
      Parameters:
      vertex - vertex whose out degree is to be calculated.
      Returns:
      the out degree of the specified vertex.

    • outgoingEdgesOf

      public Set<E> outgoingEdgesOf(V vertex)
      Returns a set of all edges outgoing from the specified vertex.
      Specified by:
      outgoingEdgesOf in interface Specifics<V,E>
      Parameters:
      vertex - the vertex for which the list of outgoing edges to be returned.
      Returns:
      a set of all edges outgoing from the specified vertex.

    • removeEdgeFromTouchingVertices

      public void removeEdgeFromTouchingVertices(V sourceVertex, V targetVertex, E e)
      Removes the specified edge from the edge containers of its source and target vertices.
      Specified by:
      removeEdgeFromTouchingVertices in interface Specifics<V,E>
      Parameters:
      sourceVertex - the source vertex
      targetVertex - the target vertex
      e - the edge

    • getEdgeContainer

      protected UndirectedEdgeContainer<V,E> getEdgeContainer(V vertex)
      Get the edge container for a specified vertex.
      Parameters:
      vertex - a vertex in this graph
      Returns:
      an edge container