Class AbstractSuccinctGraph<E>

  • Type Parameters:
    E - the graph edge type
    All Implemented Interfaces:
    java.io.Serializable, Graph<java.lang.Integer,​E>
    Direct Known Subclasses:
    AbstractSuccinctDirectedGraph, AbstractSuccinctUndirectedGraph

    public abstract class AbstractSuccinctGraph<E>
    extends AbstractGraph<java.lang.Integer,​E>
    implements java.io.Serializable
    An abstract base class for all succinct implementations.

    This class provides mutators throwing UnsupportedOperationException and operations depending only on the number of vertices and edges.

    See Also:
    Serialized Form
    • Field Summary

      Fields 
      Modifier and Type Field Description
      protected int m
      The number of edges in the graph.
      protected int n
      The number of vertices in the graph.
      protected int sourceShift
      The shift used to read sources in the successor list.
      protected long targetMask
      The mask used to read targets in the successor list (lowest sourceShift bits).
      protected static java.lang.String UNMODIFIABLE  
    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      E addEdge​(java.lang.Integer sourceVertex, java.lang.Integer targetVertex)
      Creates a new edge in this graph, going from the source vertex to the target vertex, and returns the created edge.
      boolean addEdge​(java.lang.Integer sourceVertex, java.lang.Integer targetVertex, E e)
      Adds the specified edge to this graph, going from the source vertex to the target vertex.
      java.lang.Integer addVertex()
      Creates a new vertex in this graph and returns it.
      boolean addVertex​(java.lang.Integer v)
      Adds the specified vertex to this graph if not already present.
      protected boolean assertVertexExist​(java.lang.Integer v)
      Ensures that the specified vertex exists in this graph, or else throws exception.
      boolean containsVertex​(java.lang.Integer v)
      Returns true if this graph contains the specified vertex.
      java.util.Set<E> getAllEdges​(java.lang.Integer sourceVertex, java.lang.Integer targetVertex)
      Returns a set of all edges connecting source vertex to target vertex if such vertices exist in this graph.
      java.util.function.Supplier<E> getEdgeSupplier()
      Return the edge supplier that the graph uses whenever it needs to create new edges.
      double getEdgeWeight​(E e)
      Returns the weight assigned to a given edge.
      java.util.function.Supplier<java.lang.Integer> getVertexSupplier()
      Return the vertex supplier that the graph uses whenever it needs to create new vertices.
      boolean removeEdge​(E e)
      Removes the specified edge from the graph.
      E removeEdge​(java.lang.Integer sourceVertex, java.lang.Integer targetVertex)
      Removes an edge going from source vertex to target vertex, if such vertices and such edge exist in this graph.
      boolean removeVertex​(java.lang.Integer v)
      Removes the specified vertex from this graph including all its touching edges if present.
      void setEdgeWeight​(E e, double weight)
      Assigns a weight to an edge.
      java.util.Set<java.lang.Integer> vertexSet()
      Returns a set of the vertices contained in this graph.
      • Methods inherited from class java.lang.Object

        clone, finalize, getClass, notify, notifyAll, wait, wait, wait
    • Field Detail

      • n

        protected final int n
        The number of vertices in the graph.
      • m

        protected final int m
        The number of edges in the graph.
      • sourceShift

        protected final int sourceShift
        The shift used to read sources in the successor list.
      • targetMask

        protected final long targetMask
        The mask used to read targets in the successor list (lowest sourceShift bits).
    • Constructor Detail

      • AbstractSuccinctGraph

        public AbstractSuccinctGraph​(int n,
                                     int m)
    • Method Detail

      • vertexSet

        public java.util.Set<java.lang.Integer> vertexSet()
        Description copied from interface: Graph
        Returns a set of the vertices contained in this graph. The set is backed by the graph, so changes to the graph are reflected in the set. If the graph is modified while an iteration over the set is in progress, the results of the iteration are undefined.

        The graph implementation may maintain a particular set ordering (e.g. via LinkedHashSet) for deterministic iteration, but this is not required. It is the responsibility of callers who rely on this behavior to only use graph implementations which support it.

        Specified by:
        vertexSet in interface Graph<java.lang.Integer,​E>
        Returns:
        a set view of the vertices contained in this graph.
      • assertVertexExist

        protected boolean assertVertexExist​(java.lang.Integer v)
        Ensures that the specified vertex exists in this graph, or else throws exception.
        Overrides:
        assertVertexExist in class AbstractGraph<java.lang.Integer,​E>
        Parameters:
        v - vertex
        Returns:
        true if this assertion holds.
        Throws:
        java.lang.IllegalArgumentException - if specified vertex does not exist in this graph.
      • containsVertex

        public boolean containsVertex​(java.lang.Integer v)
        Description copied from interface: Graph
        Returns true if this graph contains the specified vertex. More formally, returns true if and only if this graph contains a vertex u such that u.equals(v). If the specified vertex is null returns false.
        Specified by:
        containsVertex in interface Graph<java.lang.Integer,​E>
        Parameters:
        v - vertex whose presence in this graph is to be tested.
        Returns:
        true if this graph contains the specified vertex.
      • getAllEdges

        public java.util.Set<E> getAllEdges​(java.lang.Integer sourceVertex,
                                            java.lang.Integer targetVertex)
        Description copied from interface: Graph
        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.

        In undirected graphs, some of the returned edges may have their source and target vertices in the opposite order. In simple graphs the returned set is either singleton set or empty set.

        Specified by:
        getAllEdges in interface Graph<java.lang.Integer,​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.
      • getVertexSupplier

        public java.util.function.Supplier<java.lang.Integer> getVertexSupplier()
        Description copied from interface: Graph
        Return the vertex supplier that the graph uses whenever it needs to create new vertices.

        A graph uses the vertex supplier to create new vertex objects whenever a user calls method Graph.addVertex(). Users can also create the vertex in user code and then use method Graph.addVertex(Object) to add the vertex.

        In contrast with the Supplier interface, the vertex supplier has the additional requirement that a new and distinct result is returned every time it is invoked. More specifically for a new vertex to be added in a graph v must not be equal to any other vertex in the graph. More formally, the graph must not contain any vertex v2 such that v2.equals(v).

        Care must also be taken when interchanging calls to methods Graph.addVertex(Object) and Graph.addVertex(). In such a case the user must make sure never to add vertices in the graph using method Graph.addVertex(Object), which are going to be returned in the future by the supplied vertex supplier. Such a sequence will result into an IllegalArgumentException when calling method Graph.addVertex().

        Specified by:
        getVertexSupplier in interface Graph<java.lang.Integer,​E>
        Returns:
        the vertex supplier or null if the graph has no such supplier
      • getEdgeSupplier

        public java.util.function.Supplier<E> getEdgeSupplier()
        Description copied from interface: Graph
        Return the edge supplier that the graph uses whenever it needs to create new edges.

        A graph uses the edge supplier to create new edge objects whenever a user calls method Graph.addEdge(Object, Object). Users can also create the edge in user code and then use method Graph.addEdge(Object, Object, Object) to add the edge.

        In contrast with the Supplier interface, the edge supplier has the additional requirement that a new and distinct result is returned every time it is invoked. More specifically for a new edge to be added in a graph e must not be equal to any other edge in the graph (even if the graph allows edge-multiplicity). More formally, the graph must not contain any edge e2 such that e2.equals(e).

        Specified by:
        getEdgeSupplier in interface Graph<java.lang.Integer,​E>
        Returns:
        the edge supplier null if the graph has no such supplier
      • addEdge

        public E addEdge​(java.lang.Integer sourceVertex,
                         java.lang.Integer targetVertex)
        Description copied from interface: Graph
        Creates a new edge in this graph, going from the source vertex to the target vertex, and returns the created edge. Some graphs do not allow edge-multiplicity. In such cases, if the graph already contains an edge from the specified source to the specified target, then this method does not change the graph and returns null.

        The source and target vertices must already be contained in this graph. If they are not found in graph IllegalArgumentException is thrown.

        This method creates the new edge e using this graph's edge supplier (see Graph.getEdgeSupplier()). For the new edge to be added e must not be equal to any other edge the graph (even if the graph allows edge-multiplicity). More formally, the graph must not contain any edge e2 such that e2.equals(e). If such e2 is found then the newly created edge e is abandoned, the method leaves this graph unchanged and returns null.

        If the underlying graph implementation's Graph.getEdgeSupplier() returns null, then this method cannot create edges and throws an UnsupportedOperationException.

        Specified by:
        addEdge in interface Graph<java.lang.Integer,​E>
        Parameters:
        sourceVertex - source vertex of the edge.
        targetVertex - target vertex of the edge.
        Returns:
        The newly created edge if added to the graph, otherwise null.
        See Also:
        Graph.getEdgeSupplier()
      • addEdge

        public boolean addEdge​(java.lang.Integer sourceVertex,
                               java.lang.Integer targetVertex,
                               E e)
        Description copied from interface: Graph
        Adds the specified edge to this graph, going from the source vertex to the target vertex. More formally, adds the specified edge, e, to this graph if this graph contains no edge e2 such that e2.equals(e). If this graph already contains such an edge, the call leaves this graph unchanged and returns false. Some graphs do not allow edge-multiplicity. In such cases, if the graph already contains an edge from the specified source to the specified target, then this method does not change the graph and returns false. If the edge was added to the graph, returns true.

        The source and target vertices must already be contained in this graph. If they are not found in graph IllegalArgumentException is thrown.

        Specified by:
        addEdge in interface Graph<java.lang.Integer,​E>
        Parameters:
        sourceVertex - source vertex of the edge.
        targetVertex - target vertex of the edge.
        e - edge to be added to this graph.
        Returns:
        true if this graph did not already contain the specified edge.
        See Also:
        Graph.addEdge(Object, Object), Graph.getEdgeSupplier()
      • addVertex

        public java.lang.Integer addVertex()
        Description copied from interface: Graph
        Creates a new vertex in this graph and returns it.

        This method creates the new vertex v using this graph's vertex supplier (see Graph.getVertexSupplier()). For the new vertex to be added v must not be equal to any other vertex in the graph. More formally, the graph must not contain any vertex v2 such that v2.equals(v). If such v2 is found then the newly created vertex v is abandoned, the method leaves this graph unchanged and throws an IllegalArgumentException.

        If the underlying graph implementation's Graph.getVertexSupplier() returns null, then this method cannot create vertices and throws an UnsupportedOperationException.

        Care must also be taken when interchanging calls to methods Graph.addVertex(Object) and Graph.addVertex(). In such a case the user must make sure never to add vertices in the graph using method Graph.addVertex(Object), which are going to be returned in the future by the supplied vertex supplier. Such a sequence will result into an IllegalArgumentException when calling method Graph.addVertex().

        Specified by:
        addVertex in interface Graph<java.lang.Integer,​E>
        Returns:
        The newly created vertex if added to the graph.
        See Also:
        Graph.getVertexSupplier()
      • addVertex

        public boolean addVertex​(java.lang.Integer v)
        Description copied from interface: Graph
        Adds the specified vertex to this graph if not already present. More formally, adds the specified vertex, v, to this graph if this graph contains no vertex u such that u.equals(v). If this graph already contains such vertex, the call leaves this graph unchanged and returns false. In combination with the restriction on constructors, this ensures that graphs never contain duplicate vertices.
        Specified by:
        addVertex in interface Graph<java.lang.Integer,​E>
        Parameters:
        v - vertex to be added to this graph.
        Returns:
        true if this graph did not already contain the specified vertex.
      • removeEdge

        public E removeEdge​(java.lang.Integer sourceVertex,
                            java.lang.Integer targetVertex)
        Description copied from interface: Graph
        Removes an edge going from source vertex to target vertex, if such vertices and such edge exist in this graph. Returns the edge if removed or null otherwise.
        Specified by:
        removeEdge in interface Graph<java.lang.Integer,​E>
        Parameters:
        sourceVertex - source vertex of the edge.
        targetVertex - target vertex of the edge.
        Returns:
        The removed edge, or null if no edge removed.
      • removeEdge

        public boolean removeEdge​(E e)
        Description copied from interface: Graph
        Removes the specified edge from the graph. Removes the specified edge from this graph if it is present. More formally, removes an edge e2 such that e2.equals(e), if the graph contains such edge. Returns true if the graph contained the specified edge. (The graph will not contain the specified edge once the call returns).

        If the specified edge is null returns false.

        Specified by:
        removeEdge in interface Graph<java.lang.Integer,​E>
        Parameters:
        e - edge to be removed from this graph, if present.
        Returns:
        true if and only if the graph contained the specified edge.
      • removeVertex

        public boolean removeVertex​(java.lang.Integer v)
        Description copied from interface: Graph
        Removes the specified vertex from this graph including all its touching edges if present. More formally, if the graph contains a vertex u such that u.equals(v), the call removes all edges that touch u and then removes u itself. If no such u is found, the call leaves the graph unchanged. Returns true if the graph contained the specified vertex. (The graph will not contain the specified vertex once the call returns).

        If the specified vertex is null returns false.

        Specified by:
        removeVertex in interface Graph<java.lang.Integer,​E>
        Parameters:
        v - vertex to be removed from this graph, if present.
        Returns:
        true if the graph contained the specified vertex; false otherwise.
      • getEdgeWeight

        public double getEdgeWeight​(E e)
        Description copied from interface: Graph
        Returns the weight assigned to a given edge. Unweighted graphs return 1.0 (as defined by Graph.DEFAULT_EDGE_WEIGHT), allowing weighted-graph algorithms to apply to them when meaningful.
        Specified by:
        getEdgeWeight in interface Graph<java.lang.Integer,​E>
        Parameters:
        e - edge of interest
        Returns:
        edge weight
      • setEdgeWeight

        public void setEdgeWeight​(E e,
                                  double weight)
        Description copied from interface: Graph
        Assigns a weight to an edge.
        Specified by:
        setEdgeWeight in interface Graph<java.lang.Integer,​E>
        Parameters:
        e - edge on which to set weight
        weight - new weight for edge