Class Subgraph

java.lang.Object
org.locationtech.jts.planargraph.Subgraph

public class Subgraph extends Object
A subgraph of a PlanarGraph. A subgraph may contain any subset of Edges from the parent graph. It will also automatically contain all DirectedEdges and Nodes associated with those edges. No new objects are created when edges are added - all associated components must already exist in the parent graph.
  • Field Details

    • parentGraph

      protected PlanarGraph parentGraph
    • edges

      protected Set edges
    • dirEdges

      protected List dirEdges
    • nodeMap

      protected NodeMap nodeMap
  • Constructor Details

    • Subgraph

      public Subgraph(PlanarGraph parentGraph)
      Creates a new subgraph of the given PlanarGraph
      Parameters:
      parentGraph - the parent graph
  • Method Details

    • getParent

      public PlanarGraph getParent()
      Gets the PlanarGraph which this subgraph is part of.
      Returns:
      the parent PlanarGraph
    • add

      public void add(Edge e)
      Adds an Edge to the subgraph. The associated DirectedEdges and Nodes are also added.
      Parameters:
      e - the edge to add
    • dirEdgeIterator

      public Iterator dirEdgeIterator()
      Returns an Iterator over the DirectedEdges in this graph, in the order in which they were added.
      Returns:
      an iterator over the directed edges
      See Also:
    • edgeIterator

      public Iterator edgeIterator()
      Returns an Iterator over the Edges in this graph, in the order in which they were added.
      Returns:
      an iterator over the edges
      See Also:
    • nodeIterator

      public Iterator nodeIterator()
      Returns an Iterator over the Nodes in this graph.
      Returns:
      an iterator over the nodes
    • contains

      public boolean contains(Edge e)
      Tests whether an Edge is contained in this subgraph
      Parameters:
      e - the edge to test
      Returns:
      true if the edge is contained in this subgraph