Class ImmutableValueGraphAdapter<V,​W>

  • Type Parameters:
    V - the graph vertex type
    W - the value type
    All Implemented Interfaces:
    Serializable, Cloneable, Graph<V,​com.google.common.graph.EndpointPair<V>>
    Direct Known Subclasses:
    ImmutableDoubleValueGraphAdapter

    public class ImmutableValueGraphAdapter<V,​W>
    extends BaseValueGraphAdapter<V,​W,​com.google.common.graph.ImmutableValueGraph<V,​W>>
    implements Graph<V,​com.google.common.graph.EndpointPair<V>>, Cloneable, Serializable
    A graph adapter class using Guava's ImmutableValueGraph.

    The adapter uses class EndpointPair to represent edges. Since the underlying value graph is immutable, the resulting graph is unmodifiable.

    The class uses a converter from Guava's values to JGraphT's double weights. Thus, the resulting graph is weighted.

    Assume for example that the following class is the value type:

     class MyValue
         implements Serializable
     {
         private double value;
    
         public MyValue(double value)
         {
             this.value = value;
         }
    
         public double getValue()
         {
             return value;
         }
     }
     
    Then one could create an adapter using the following code:
     MutableValueGraph<String, MyValue> valueGraph =
         ValueGraphBuilder.directed().allowsSelfLoops(true).build();
     valueGraph.addNode("v1");
     valueGraph.addNode("v2");
     valueGraph.putEdgeValue("v1", "v2", new MyValue(5.0));
     
     ImmutableValueGraph<String, MyValue> immutableValueGraph =
         ImmutableValueGraph.copyOf(valueGraph);
     
     Graph<String, EndpointPair<String>> graph = new ImmutableValueGraphAdapter<>(
         immutableValueGraph, (ToDoubleFunction<MyValue> & Serializable) MyValue::getValue);
     
     double weight = graph.getEdgeWeight(EndpointPair.ordered("v1", "v2")); // should return 5.0
     
    Author:
    Dimitrios Michail
    See Also:
    Serialized Form
    • Constructor Detail

      • ImmutableValueGraphAdapter

        public ImmutableValueGraphAdapter​(com.google.common.graph.ImmutableValueGraph<V,​W> valueGraph,
                                          ToDoubleFunction<W> valueConverter)
        Create a new adapter.
        Parameters:
        valueGraph - the value graph
        valueConverter - a function that converts a value to a double
        Throws:
        NullPointerException - if either one of valueGraph or valueConverter is null
    • Method Detail

      • addEdge

        public com.google.common.graph.EndpointPair<V> addEdge​(V sourceVertex,
                                                               V 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<V,​W>
        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.
        Throws:
        UnsupportedOperationException - always
        See Also:
        Graph.getEdgeSupplier()
      • addEdge

        public boolean addEdge​(V sourceVertex,
                               V targetVertex,
                               com.google.common.graph.EndpointPair<V> 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.
        Specified by:
        addEdge in interface Graph<V,​W>
        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.
        Throws:
        UnsupportedOperationException - always
        See Also:
        Graph.addEdge(Object, Object), Graph.getEdgeSupplier()
      • addVertex

        public boolean addVertex​(V 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<V,​W>
        Parameters:
        v - vertex to be added to this graph.
        Returns:
        true if this graph did not already contain the specified vertex.
        Throws:
        UnsupportedOperationException - always
      • removeEdge

        public com.google.common.graph.EndpointPair<V> removeEdge​(V sourceVertex,
                                                                  V 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<V,​W>
        Parameters:
        sourceVertex - source vertex of the edge.
        targetVertex - target vertex of the edge.
        Returns:
        The removed edge, or null if no edge removed.
        Throws:
        UnsupportedOperationException - always
      • removeEdge

        public boolean removeEdge​(com.google.common.graph.EndpointPair<V> 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<V,​W>
        Parameters:
        e - edge to be removed from this graph, if present.
        Returns:
        true if and only if the graph contained the specified edge.
        Throws:
        UnsupportedOperationException - always
      • removeVertex

        public boolean removeVertex​(V 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<V,​W>
        Parameters:
        v - vertex to be removed from this graph, if present.
        Returns:
        true if the graph contained the specified vertex; false otherwise.
        Throws:
        UnsupportedOperationException - always
      • setEdgeWeight

        public void setEdgeWeight​(com.google.common.graph.EndpointPair<V> e,
                                  double weight)
        Description copied from interface: Graph
        Assigns a weight to an edge.
        Specified by:
        setEdgeWeight in interface Graph<V,​W>
        Parameters:
        e - edge on which to set weight
        weight - new weight for edge
        Throws:
        UnsupportedOperationException - always
      • getType

        public GraphType getType()
        Description copied from interface: Graph
        Get the graph type. The graph type can be used to query for additional metadata such as whether the graph supports directed or undirected edges, self-loops, multiple (parallel) edges, weights, etc.
        Specified by:
        getType in interface Graph<V,​W>
        Overrides:
        getType in class BaseValueGraphAdapter<V,​W,​com.google.common.graph.ImmutableValueGraph<V,​W>>
        Returns:
        the graph type
      • clone

        public Object clone()
        Returns a shallow copy of this graph instance. Neither edges nor vertices are cloned.
        Overrides:
        clone in class Object
        Returns:
        a shallow copy of this graph.
        Throws:
        RuntimeException - in case the clone is not supported
        See Also:
        Object.clone()