mwalk.visitor
Interface DownVisitor

All Known Implementing Classes:

DataVisitor, ExportVisitor, GlobalVisitor, LinkCountVisitor, MetricVisitor, VisualVisitor, MergeVisitor, DegreeCountVisitor, CollapseVisitor

public interface DownVisitor

extends Visitor

A standard interface used to interact with visitors that walk the tree from the top down.

Version:

1.0

Author:

Robert Chalmers

Method Summary

TreeNode[]	getChildren(Tree tree, TreeNode node) Get a list of children for the current node applying correct activity semantics.
java.lang.Object	visitDown(Tree tree, TreeNode node) Visit the current node prior to visiting children.
java.lang.Object	visitDown(Tree tree, TreeNode node, java.util.Vector list) Visit the current node after visiting children.
boolean	walkDown() Whether to walk down the tree.

Methods inherited from interface mwalk.visitor.Visitor

again, evaluator, evaluator, init, postfix, prefix, reset, verbose

Method Detail

walkDown

public boolean walkDown()

Whether to walk down the tree.

Returns:

boolean whether to walk down the tree

visitDown

public java.lang.Object visitDown(Tree tree,
                                  TreeNode node)
                           throws VisitException

Visit the current node prior to visiting children. This method is called if prefix() returns true.

Parameters:

Tree - current tree instance

TreeNode - current node

Returns:

Object optional return value to pass back along the path

Throws:

VisitException - if a problem ocurred during visit

visitDown

public java.lang.Object visitDown(Tree tree,
                                  TreeNode node,
                                  java.util.Vector list)
                           throws VisitException

Visit the current node after visiting children. This method is called if postfix() returns true.

Parameters:

Tree - current tree instance

TreeNode - current node

Vector - list of return values passed back along the path

Returns:

Object optional return value to pass back along the path

Throws:

VisitException - if a problem ocurred during visit

getChildren

public TreeNode[] getChildren(Tree tree,
                              TreeNode node)

Get a list of children for the current node applying correct activity semantics.

Parameters:

Tree - current tree instance

TreeNode - current node

Returns:

TreeNode[] list of active children nodes