Package org.parboiled.trees

Class GraphUtils

java.lang.Object
org.parboiled.trees.GraphUtils
public final class GraphUtils extends Object
General utility methods for operating on directed graphs (consisting of GraphNodes).

  • Method Summary

    Modifier and Type
    Method
    Description
    static <T extends GraphNode<T>, C extends Collection<T>>
    C
    collectAllNodes(T node, C collection)
    Collects all nodes from the graph reachable from the given node in the given collection.
    static <T extends GraphNode<T>>
    int
    countAllDistinct(T node)
    Counts all distinct nodes in the graph reachable from the given node.
    static <T extends GraphNode<T>>
    T
    getFirstChild(T node)
    Returns the first child node of the given node or null if node is null or does not have any children.
    static <T extends GraphNode<T>>
    T
    getLastChild(T node)
    Returns the last child node of the given node or null if node is null or does not have any children.
    static boolean
    hasChildren(GraphNode<?> node)
    Returns true if this node is not null and has at least one child node.
    static <T extends GraphNode<T>>
    String
    printTree(T node, Formatter<T> formatter)
    Creates a string representation of the graph reachable from the given node using the given formatter.
    static <T extends GraphNode<T>>
    String
    printTree(T node, Formatter<T> formatter, Predicate<T> nodeFilter, Predicate<T> subTreeFilter)
    Creates a string representation of the graph reachable from the given node using the given formatter.

    Methods inherited from class java.lang.Object

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

  • Method Details

    • hasChildren

      public static boolean hasChildren(GraphNode<?> node)
      Returns true if this node is not null and has at least one child node.
      Parameters:
      node - a node
      Returns:
      true if this node is not null and has at least one child node.

    • getFirstChild

      public static <T extends GraphNode<T>> T getFirstChild(T node)
      Returns the first child node of the given node or null if node is null or does not have any children.
      Parameters:
      node - a node
      Returns:
      the first child node of the given node or null if node is null or does not have any children

    • getLastChild

      public static <T extends GraphNode<T>> T getLastChild(T node)
      Returns the last child node of the given node or null if node is null or does not have any children.
      Parameters:
      node - a node
      Returns:
      the last child node of the given node or null if node is null or does not have any children

    • countAllDistinct

      public static <T extends GraphNode<T>> int countAllDistinct(T node)
      Counts all distinct nodes in the graph reachable from the given node. This method can properly deal with cycles in the graph.
      Parameters:
      node - the root node
      Returns:
      the number of distinct nodes

    • collectAllNodes

      public static <T extends GraphNode<T>, C extends Collection<T>> C collectAllNodes(T node, C collection)
      Collects all nodes from the graph reachable from the given node in the given collection. This method can properly deal with cycles in the graph.
      Parameters:
      node - the root node
      collection - the collection to collect into
      Returns:
      the same collection passed as a parameter

    • printTree

      public static <T extends GraphNode<T>> String printTree(T node, Formatter<T> formatter)
      Creates a string representation of the graph reachable from the given node using the given formatter.
      Parameters:
      node - the root node
      formatter - the node formatter
      Returns:
      a new string

    • printTree

      public static <T extends GraphNode<T>> String printTree(T node, Formatter<T> formatter, Predicate<T> nodeFilter, Predicate<T> subTreeFilter)
      Creates a string representation of the graph reachable from the given node using the given formatter. The given filter predicated determines whether a particular node (and its subtree respectively) is to be printed or not.
      Parameters:
      node - the root node
      formatter - the node formatter
      nodeFilter - the predicate selecting the nodes to print
      subTreeFilter - the predicate determining whether to descend into a given nodes subtree or not
      Returns:
      a new string