Method Detail

• addNode

  boolean addNode(N node)

  Adds node if it is not already present.

  Nodes must be unique, just as Map keys must be. They must also be non-null.

  Returns:

  true if the graph was modified as a result of this call

• putEdge

  boolean putEdge(N nodeU,
                N nodeV)

  Adds an edge connecting nodeU to nodeV if one is not already present. In an undirected graph, the edge will also connect nodeV to nodeU.

  Behavior if nodeU and nodeV are not already present in this graph is implementation-dependent. Suggested behaviors include (a) silently adding nodeU and nodeV to the graph (this is the behavior of the default implementations) or (b) throwing IllegalArgumentException.

  Returns:

  true if the graph was modified as a result of this call

  Throws:

  IllegalArgumentException - if the introduction of the edge would violate Graph.allowsSelfLoops()

• removeNode

  boolean removeNode(Object node)

  Removes node if it is present; all edges incident to node will also be removed.

  Returns:

  true if the graph was modified as a result of this call

• removeEdge

  boolean removeEdge(Object nodeU,
                   Object nodeV)

  Removes the edge connecting nodeU to nodeV, if it is present.

  Returns:

  true if the graph was modified as a result of this call