Package org.geotools.graph.path

Class Walk

  • All Implemented Interfaces:
    Serializable, Cloneable, Iterable<Node>, Collection<Node>, List<Node>, RandomAccess, NodeSequence
    Direct Known Subclasses:
    Cycle, Path
    public class Walk
extends ArrayList<Node>
implements NodeSequence
    Represents a walk in a graph. A walk W is defined as an ordered set of nodes that two adjacenct nodes in the set share an edge. More precisley:

    G = {N,E} W = { n(i) in N | (n(i-1),n(i)) in E }
    Author:
    Justin Deoliveira, Refractions Research Inc, jdeolive@refractions.net
    See Also:
    Serialized Form

    • Field Summary

      • Fields inherited from class AbstractList

        modCount

    • Constructor Summary

      Constructors 
      Constructor Description
      Walk()  
      Walk​(Collection<Node> nodes)  

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void add​(int index, Node element)  
      boolean add​(Node node)
      Adds a node to the walk.
      boolean addAll​(int index, Collection<? extends Node> c)  
      boolean addAll​(Collection<? extends Node> c)  
      boolean addEdge​(Edge e)  
      void addEdges​(Collection<Edge> edges)  
      protected List<Edge> buildEdges()
      Internal method for building the edge set of the walk.
      Path duplicate()  
      boolean equals​(Object other)  
      boolean equals​(Walk other)  
      List<Edge> getEdges()
      Calculates the edges in the walk.
      Node getFirst()
      Returns the first node in the sequence.
      Node getLast()
      Returns the last node in the sequence.
      int hashCode()  
      boolean isClosed()
      Determines if the walk is closed.
      boolean isValid()
      A valid walk is one in which each pair of adjacent nodes in the sequence share an edge.
      Node remove​(int index)  
      boolean remove​(Object o)  
      void remove​(Node node)
      Removes a node from the walk.
      boolean removeAll​(Collection c)  
      void reverse()
      Reverses the path.
      Iterator<Node> riterator()
      Returns an iterator that iterates over the path in reverse.
      void truncate​(int index)
      Truncates the path at the specified index.

      • Methods inherited from class ArrayList

        clear, clone, contains, ensureCapacity, forEach, get, indexOf, isEmpty, iterator, lastIndexOf, listIterator, listIterator, removeIf, removeRange, replaceAll, retainAll, set, size, sort, spliterator, subList, toArray, toArray, trimToSize

      • Methods inherited from class AbstractCollection

        containsAll, toString

      • Methods inherited from class Object

        finalize, getClass, notify, notifyAll, wait, wait, wait

      • Methods inherited from interface Collection

        parallelStream, stream, toArray

      • Methods inherited from interface List

        containsAll

    • Constructor Detail

      • Walk

        public Walk()

      • Walk

        public Walk​(Collection<Node> nodes)

    • Method Detail

      • isValid

        public boolean isValid()
        A valid walk is one in which each pair of adjacent nodes in the sequence share an edge. Note,
        Specified by:
        isValid in interface NodeSequence
        Returns:
        True if valid, otherwise false.

      • getEdges

        public List<Edge> getEdges()
        Calculates the edges in the walk. If the edges of the walk cannot be calculated (due to an invalid walk), null is returned, otherwise the list of edges is returned.
        Returns:
        The edges of the walk, otherwise null if the edges cannot be calculated.

      • add

        public boolean add​(Node node)
        Adds a node to the walk. Adding a node clears the edge list which will be recalculated on the next call to getEdges().
        Specified by:
        add in interface Collection<Node>
        Specified by:
        add in interface List<Node>
        Overrides:
        add in class ArrayList<Node>
        Parameters:
        node - Node to add to the walk.

      • add

        public void add​(int index,
                Node element)
        Specified by:
        add in interface List<Node>
        Overrides:
        add in class ArrayList<Node>

      • addAll

        public boolean addAll​(Collection<? extends Node> c)
        Specified by:
        addAll in interface Collection<Node>
        Specified by:
        addAll in interface List<Node>
        Overrides:
        addAll in class ArrayList<Node>

      • addAll

        public boolean addAll​(int index,
                      Collection<? extends Node> c)
        Specified by:
        addAll in interface List<Node>
        Overrides:
        addAll in class ArrayList<Node>

      • addEdge

        public boolean addEdge​(Edge e)

      • addEdges

        public void addEdges​(Collection<Edge> edges)

      • remove

        public void remove​(Node node)
        Removes a node from the walk. Removing a node clears the edge list which will be recalculated on the next call to getEdges().
        Parameters:
        node - Node to remove from the walk.

      • remove

        public Node remove​(int index)
        Specified by:
        remove in interface List<Node>
        Overrides:
        remove in class ArrayList<Node>

      • remove

        public boolean remove​(Object o)
        Specified by:
        remove in interface Collection<Node>
        Specified by:
        remove in interface List<Node>
        Overrides:
        remove in class ArrayList<Node>

      • removeAll

        public boolean removeAll​(Collection c)
        Specified by:
        removeAll in interface Collection<Node>
        Specified by:
        removeAll in interface List<Node>
        Overrides:
        removeAll in class ArrayList<Node>

      • isClosed

        public boolean isClosed()
        Determines if the walk is closed. A closed walk is one in which the first and last nodes are the same.
        Returns:
        True if closed, otherwise false.

      • buildEdges

        protected List<Edge> buildEdges()
        Internal method for building the edge set of the walk. This method calculated the edges upon every call.
        Returns:
        The list of edges for the walk, or null if the edge set could not be calculated due to an invalid walk.

      • reverse

        public void reverse()
        Reverses the path.

      • truncate

        public void truncate​(int index)
        Truncates the path at the specified index. Nodes in the path whose index is >= the specified index are removed.
        Parameters:
        index - The index of first node to be removed.

      • riterator

        public Iterator<Node> riterator()
        Returns an iterator that iterates over the path in reverse. The iterator does not support the remove operation.
        Returns:
        the reverse iterator.

      • duplicate

        public Path duplicate()

      • equals

        public boolean equals​(Object other)
        Specified by:
        equals in interface Collection<Node>
        Specified by:
        equals in interface List<Node>
        Overrides:
        equals in class ArrayList<Node>

      • equals

        public boolean equals​(Walk other)

      • hashCode

        public int hashCode()
        Specified by:
        hashCode in interface Collection<Node>
        Specified by:
        hashCode in interface List<Node>
        Overrides:
        hashCode in class ArrayList<Node>