Class GraphDelegator

  • All Implemented Interfaces:
    java.io.Serializable, Graph
    Direct Known Subclasses:
    AsUndirectedGraph, DefaultListenableGraph, UnmodifiableGraph

    public class GraphDelegator
    extends AbstractGraph
    implements Graph, java.io.Serializable
    A graph backed by the the graph specified at the constructor, which delegates all its methods to the backing graph. Operations on this graph "pass through" to the to the backing graph. Any modification made to this graph or the backing graph is reflected by the other.

    This graph does not pass the hashCode and equals operations through to the backing graph, but relies on Object's equals and hashCode methods.

    This class is mostly used as a base for extending subclasses.

    Since:
    Jul 20, 2003
    Author:
    Barak Naveh
    See Also:
    Serialized Form
    • Constructor Summary

      Constructors 
      Constructor Description
      GraphDelegator​(Graph g)
      Constructor for GraphDelegator.
    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      Edge addEdge​(java.lang.Object sourceVertex, java.lang.Object targetVertex)
      Creates a new edge in this graph, going from the source vertex to the target vertex, and returns the created edge.
      boolean addEdge​(Edge e)
      Adds the specified edge to this graph.
      boolean addVertex​(java.lang.Object v)
      Adds the specified vertex to this graph if not already present.
      boolean containsEdge​(Edge e)
      Returns true if this graph contains the specified edge.
      boolean containsVertex​(java.lang.Object v)
      Returns true if this graph contains the specified vertex.
      int degreeOf​(java.lang.Object vertex)  
      java.util.Set edgeSet()
      Returns a set of the edges contained in this graph.
      java.util.List edgesOf​(java.lang.Object vertex)
      Returns a list of all edges touching the specified vertex.
      java.util.List getAllEdges​(java.lang.Object sourceVertex, java.lang.Object targetVertex)
      Returns a list of all edges connecting source vertex to target vertex if such vertices exist in this graph.
      Edge getEdge​(java.lang.Object sourceVertex, java.lang.Object targetVertex)
      Returns an edge connecting source vertex to target vertex if such vertices and such edge exist in this graph.
      EdgeFactory getEdgeFactory()
      Returns the edge factory using which this graph creates new edges.
      java.util.List incomingEdgesOf​(java.lang.Object vertex)  
      int inDegreeOf​(java.lang.Object vertex)  
      int outDegreeOf​(java.lang.Object vertex)  
      java.util.List outgoingEdgesOf​(java.lang.Object vertex)  
      Edge removeEdge​(java.lang.Object sourceVertex, java.lang.Object targetVertex)
      Removes an edge going from source vertex to target vertex, if such vertices and such edge exist in this graph.
      boolean removeEdge​(Edge e)
      Removes the specified edge from the graph.
      boolean removeVertex​(java.lang.Object v)
      Removes the specified vertex from this graph including all its touching edges if present.
      java.lang.String toString()
      Returns a string of the parenthesized pair (V, E) representing this G=(V,E) graph.
      java.util.Set vertexSet()
      Returns a set of the vertices contained in this graph.
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
    • Constructor Detail

      • GraphDelegator

        public GraphDelegator​(Graph g)
        Constructor for GraphDelegator.
        Parameters:
        g - the backing graph (the delegate).
        Throws:
        java.lang.NullPointerException
    • Method Detail

      • getAllEdges

        public java.util.List getAllEdges​(java.lang.Object sourceVertex,
                                          java.lang.Object targetVertex)
        Description copied from interface: Graph
        Returns a list 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 list.

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

        Specified by:
        getAllEdges in interface Graph
        Parameters:
        sourceVertex - source vertex of the edge.
        targetVertex - target vertex of the edge.
        Returns:
        a list of all edges connecting source vertex to target vertex.
        See Also:
        Graph.getAllEdges(Object, Object)
      • getEdge

        public Edge getEdge​(java.lang.Object sourceVertex,
                            java.lang.Object targetVertex)
        Description copied from interface: Graph
        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 Graph
        Parameters:
        sourceVertex - source vertex of the edge.
        targetVertex - target vertex of the edge.
        Returns:
        an edge connecting source vertex to target vertex.
        See Also:
        Graph.getEdge(Object, Object)
      • getEdgeFactory

        public EdgeFactory getEdgeFactory()
        Description copied from interface: Graph
        Returns the edge factory using which this graph creates new edges. The edge factory is defined when the graph is constructed and must not be modified.
        Specified by:
        getEdgeFactory in interface Graph
        Returns:
        the edge factory using which this graph creates new edges.
        See Also:
        Graph.getEdgeFactory()
      • addEdge

        public boolean addEdge​(Edge e)
        Description copied from interface: Graph
        Adds the specified edge to this graph. 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 edge, the call leaves this graph unchanged and returns false. If the edge was added to the graph, returns true.

        Some graphs do not allow edge-multiplicity. In such cases, if the graph already contains an edge going from e.getSource() vertex to e.getTarget() vertex, than this method does not change the graph and returns false.

        The source and target vertices of the specified edge must already be in this graph. If this is not the case, IllegalArgumentException is thrown. The edge must also be assignment compatible with the class of the edges produced by the edge factory of this graph. If this is not the case ClassCastException is thrown.

        Specified by:
        addEdge in interface Graph
        Parameters:
        e - edge to be added to this graph.
        Returns:
        true if this graph did not already contain the specified edge.
        See Also:
        Graph.addEdge(Edge)
      • addEdge

        public Edge addEdge​(java.lang.Object sourceVertex,
                            java.lang.Object 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, than 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 EdgeFactory. 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 returns null.

        Specified by:
        addEdge in interface Graph
        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.addEdge(Object, Object)
      • addVertex

        public boolean addVertex​(java.lang.Object 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
        Parameters:
        v - vertex to be added to this graph.
        Returns:
        true if this graph did not already contain the specified vertex.
        See Also:
        Graph.addVertex(Object)
      • containsEdge

        public boolean containsEdge​(Edge e)
        Description copied from interface: Graph
        Returns true if this graph contains the specified edge. More formally, returns true if and only if this graph contains an edge e2 such that e.equals(e2). If the specified edge is null returns false.
        Specified by:
        containsEdge in interface Graph
        Parameters:
        e - edge whose presence in this graph is to be tested.
        Returns:
        true if this graph contains the specified edge.
        See Also:
        Graph.containsEdge(Edge)
      • containsVertex

        public boolean containsVertex​(java.lang.Object 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
        Parameters:
        v - vertex whose presence in this graph is to be tested.
        Returns:
        true if this graph contains the specified vertex.
        See Also:
        Graph.containsVertex(Object)
      • edgeSet

        public java.util.Set edgeSet()
        Description copied from interface: Graph
        Returns a set of the edges 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:
        edgeSet in interface Graph
        Returns:
        a set of the edges contained in this graph.
        See Also:
        Graph.edgeSet()
      • edgesOf

        public java.util.List edgesOf​(java.lang.Object vertex)
        Description copied from interface: Graph
        Returns a list of all edges touching the specified vertex. If no edges are touching the specified vertex returns an empty list.
        Specified by:
        edgesOf in interface Graph
        Parameters:
        vertex - the vertex for which a list of touching edges to be returned.
        Returns:
        a list of all edges touching the specified vertex.
        See Also:
        Graph.edgesOf(Object)
      • removeEdge

        public boolean removeEdge​(Edge 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
        Parameters:
        e - edge to be removed from this graph, if present.
        Returns:
        true if and only if the graph contained the specified edge.
        See Also:
        Graph.removeEdge(Edge)
      • removeEdge

        public Edge removeEdge​(java.lang.Object sourceVertex,
                               java.lang.Object 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
        Parameters:
        sourceVertex - source vertex of the edge.
        targetVertex - target vertex of the edge.
        Returns:
        The removed edge, or null if no edge removed.
        See Also:
        Graph.removeEdge(Object, Object)
      • removeVertex

        public boolean removeVertex​(java.lang.Object 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
        Parameters:
        v - vertex to be removed from this graph, if present.
        Returns:
        true if the graph contained the specified vertex; false otherwise.
        See Also:
        Graph.removeVertex(Object)
      • toString

        public java.lang.String toString()
        Description copied from class: AbstractGraph
        Returns a string of the parenthesized pair (V, E) representing this G=(V,E) graph. 'V' is the string representation of the vertex set, and 'E' is the string representation of the edge set.
        Overrides:
        toString in class AbstractGraph
        Returns:
        a string representation of this graph.
        See Also:
        Object.toString()
      • vertexSet

        public java.util.Set 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
        Returns:
        a set view of the vertices contained in this graph.
        See Also:
        Graph.vertexSet()