Package org.antlr.misc

Class Graph<T>

  • public class Graph<T>
extends java.lang.Object
    A generic graph with edges; Each node as a single Object payload. This is only used to topologically sort a list of file dependencies at the moment.

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description
      static class  Graph.Node<T>  

    • Field Summary

      Fields 
      Modifier and Type Field Description
      protected java.util.Map<T,​Graph.Node<T>> nodes
      Map from node payload to node containing it

    • Constructor Summary

      Constructors 
      Constructor Description
      Graph()  

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void addEdge​(T a, T b)  
      void DFS​(Graph.Node<T> n, java.util.Set<Graph.Node<T>> visited, java.util.ArrayList<T> sorted)  
      protected Graph.Node<T> getNode​(T a)  
      java.util.List<T> sort()
      DFS-based topological sort.

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Field Detail

      • nodes

        protected java.util.Map<T,​Graph.Node<T>> nodes
        Map from node payload to node containing it

    • Constructor Detail

      • Graph

        public Graph()

    • Method Detail

      • addEdge

        public void addEdge​(T a,
                    T b)

      • sort

        public java.util.List<T> sort()
        DFS-based topological sort. A valid sort is the reverse of the post-order DFA traversal. Amazingly simple but true. For sorting, I'm not following convention here since ANTLR needs the opposite. Here's what I assume for sorting: If there exists an edge u → v then u depends on v and v must happen before u. So if this gives nonreversed postorder traversal, I get the order I want.

      • DFS

        public void DFS​(Graph.Node<T> n,
                java.util.Set<Graph.Node<T>> visited,
                java.util.ArrayList<T> sorted)