Class ForwardingValueGraph<N,V>

All Implemented Interfaces:
BaseGraph<N>, PredecessorsFunction<N>, SuccessorsFunction<N>, ValueGraph<N,V>
Direct Known Subclasses:
Graphs.TransposedValueGraph

abstract class ForwardingValueGraph<N,V> extends AbstractValueGraph<N,V>
A class to allow ValueGraph implementations to be backed by a provided delegate. This is not currently planned to be released as a general-purpose forwarding class.
  • Constructor Details

    • ForwardingValueGraph

      ForwardingValueGraph()
  • Method Details

    • delegate

      abstract ValueGraph<N,V> delegate()
    • nodes

      public Set<N> nodes()
      Description copied from interface: ValueGraph
      Returns all nodes in this graph, in the order specified by ValueGraph.nodeOrder().
    • edgeCount

      protected long edgeCount()
      Defer to AbstractBaseGraph.edges() (based on successors(Object)) for full edges() implementation.
      Overrides:
      edgeCount in class AbstractBaseGraph<N>
    • isDirected

      public boolean isDirected()
      Description copied from interface: ValueGraph
      Returns true if the edges in this graph are directed. Directed edges connect a source node to a target node, while undirected edges connect a pair of nodes to each other.
    • allowsSelfLoops

      public boolean allowsSelfLoops()
      Description copied from interface: ValueGraph
      Returns true if this graph allows self-loops (edges that connect a node to itself). Attempting to add a self-loop to a graph that does not allow them will throw an IllegalArgumentException.
    • nodeOrder

      public ElementOrder<N> nodeOrder()
      Description copied from interface: ValueGraph
      Returns the order of iteration for the elements of ValueGraph.nodes().
    • incidentEdgeOrder

      public ElementOrder<N> incidentEdgeOrder()
      Description copied from interface: BaseGraph
      Specified by:
      incidentEdgeOrder in interface BaseGraph<N>
      Specified by:
      incidentEdgeOrder in interface ValueGraph<N,V>
      Overrides:
      incidentEdgeOrder in class AbstractBaseGraph<N>
    • adjacentNodes

      public Set<N> adjacentNodes(N node)
      Description copied from interface: ValueGraph
      Returns a live view of the nodes which have an incident edge in common with node in this graph.

      This is equal to the union of ValueGraph.predecessors(Object) and ValueGraph.successors(Object).

      If node is removed from the graph after this method is called, the Set view returned by this method will be invalidated, and will throw IllegalStateException if it is accessed in any way, with the following exceptions:

      • view.equals(view) evaluates to true (but any other `equals()` expression involving view will throw)
      • hashCode() does not throw
      • if node is re-added to the graph after having been removed, view's behavior is undefined
    • predecessors

      public Set<N> predecessors(N node)
      Description copied from interface: ValueGraph
      Returns a live view of all nodes in this graph adjacent to node which can be reached by traversing node's incoming edges against the direction (if any) of the edge.

      In an undirected graph, this is equivalent to ValueGraph.adjacentNodes(Object).

      If node is removed from the graph after this method is called, the `Set` returned by this method will be invalidated, and will throw `IllegalStateException` if it is accessed in any way.

    • successors

      public Set<N> successors(N node)
      Description copied from interface: ValueGraph
      Returns a live view of all nodes in this graph adjacent to node which can be reached by traversing node's outgoing edges in the direction (if any) of the edge.

      In an undirected graph, this is equivalent to ValueGraph.adjacentNodes(Object).

      This is not the same as "all nodes reachable from node by following outgoing edges". For that functionality, see Graphs.reachableNodes(Graph, Object).

      If node is removed from the graph after this method is called, the Set view returned by this method will be invalidated, and will throw IllegalStateException if it is accessed in any way, with the following exceptions:

      • view.equals(view) evaluates to true (but any other `equals()` expression involving view will throw)
      • hashCode() does not throw
      • if node is re-added to the graph after having been removed, view's behavior is undefined
    • degree

      public int degree(N node)
      Description copied from interface: BaseGraph
      Returns the count of node's incident edges, counting self-loops twice (equivalently, the number of times an edge touches node).

      For directed graphs, this is equal to inDegree(node) + outDegree(node).

      For undirected graphs, this is equal to incidentEdges(node).size() + (number of self-loops incident to node).

      If the count is greater than Integer.MAX_VALUE, returns Integer.MAX_VALUE.

      Specified by:
      degree in interface BaseGraph<N>
      Specified by:
      degree in interface ValueGraph<N,V>
      Overrides:
      degree in class AbstractBaseGraph<N>
    • inDegree

      public int inDegree(N node)
      Description copied from interface: BaseGraph
      Returns the count of node's incoming edges (equal to predecessors(node).size()) in a directed graph. In an undirected graph, returns the BaseGraph.degree(Object).

      If the count is greater than Integer.MAX_VALUE, returns Integer.MAX_VALUE.

      Specified by:
      inDegree in interface BaseGraph<N>
      Specified by:
      inDegree in interface ValueGraph<N,V>
      Overrides:
      inDegree in class AbstractBaseGraph<N>
    • outDegree

      public int outDegree(N node)
      Description copied from interface: BaseGraph
      Returns the count of node's outgoing edges (equal to successors(node).size()) in a directed graph. In an undirected graph, returns the BaseGraph.degree(Object).

      If the count is greater than Integer.MAX_VALUE, returns Integer.MAX_VALUE.

      Specified by:
      outDegree in interface BaseGraph<N>
      Specified by:
      outDegree in interface ValueGraph<N,V>
      Overrides:
      outDegree in class AbstractBaseGraph<N>
    • hasEdgeConnecting

      public boolean hasEdgeConnecting(N nodeU, N nodeV)
      Description copied from interface: BaseGraph
      Returns true if there is an edge that directly connects nodeU to nodeV. This is equivalent to nodes().contains(nodeU) && successors(nodeU).contains(nodeV).

      In an undirected graph, this is equal to hasEdgeConnecting(nodeV, nodeU).

      Specified by:
      hasEdgeConnecting in interface BaseGraph<N>
      Specified by:
      hasEdgeConnecting in interface ValueGraph<N,V>
      Overrides:
      hasEdgeConnecting in class AbstractBaseGraph<N>
    • hasEdgeConnecting

      public boolean hasEdgeConnecting(EndpointPair<N> endpoints)
      Description copied from interface: BaseGraph
      Returns true if there is an edge that directly connects endpoints (in the order, if any, specified by endpoints). This is equivalent to edges().contains(endpoints).

      Unlike the other EndpointPair-accepting methods, this method does not throw if the endpoints are unordered; it simply returns false. This is for consistency with the behavior of

      invalid reference
      Collection#contains(Object)
      (which does not generally throw if the object cannot be present in the collection), and the desire to have this method's behavior be compatible with edges().contains(endpoints).
      Specified by:
      hasEdgeConnecting in interface BaseGraph<N>
      Specified by:
      hasEdgeConnecting in interface ValueGraph<N,V>
      Overrides:
      hasEdgeConnecting in class AbstractBaseGraph<N>
    • edgeValue

      public Optional<V> edgeValue(N nodeU, N nodeV)
      Description copied from interface: ValueGraph
      Returns the value of the edge that connects nodeU to nodeV (in the order, if any, specified by endpoints), if one is present; otherwise, returns Optional.empty().
      Specified by:
      edgeValue in interface ValueGraph<N,V>
      Overrides:
      edgeValue in class AbstractValueGraph<N,V>
    • edgeValue

      public Optional<V> edgeValue(EndpointPair<N> endpoints)
      Description copied from interface: ValueGraph
      Returns the value of the edge that connects endpoints (in the order, if any, specified by endpoints), if one is present; otherwise, returns Optional.empty().

      If this graph is directed, the endpoints must be ordered.

      Specified by:
      edgeValue in interface ValueGraph<N,V>
      Overrides:
      edgeValue in class AbstractValueGraph<N,V>
    • edgeValueOrDefault

      @CheckForNull public V edgeValueOrDefault(N nodeU, N nodeV, @CheckForNull V defaultValue)
      Description copied from interface: ValueGraph
      Returns the value of the edge that connects nodeU to nodeV, if one is present; otherwise, returns defaultValue.

      In an undirected graph, this is equal to edgeValueOrDefault(nodeV, nodeU, defaultValue).

    • edgeValueOrDefault

      @CheckForNull public V edgeValueOrDefault(EndpointPair<N> endpoints, @CheckForNull V defaultValue)
      Description copied from interface: ValueGraph
      Returns the value of the edge that connects endpoints (in the order, if any, specified by endpoints), if one is present; otherwise, returns defaultValue.

      If this graph is directed, the endpoints must be ordered.