org.jikesrvm.compilers.opt.util

Class TreeBottomUpEnumerator

java.lang.Object

org.jikesrvm.compilers.opt.util.TreeBottomUpEnumerator

All Implemented Interfaces:

Enumeration<TreeNode>

final class TreeBottomUpEnumerator
extends Object
implements Enumeration<TreeNode>

This class provides enumeration of a tree in bottom-up order It guarantees that all children of a node will be visited before the parent. This is not necessarily the same as a bottom-up level walk.

Field Summary

Fields

Modifier and Type	Field and Description
private ListIterator<TreeNode>	iterator an iterator of the above list
private ArrayList<TreeNode>	list List of nodes in postorder

Constructor Summary

Constructors

Constructor and Description
TreeBottomUpEnumerator(TreeNode root) constructor: it creates the list of nodes

Method Summary

Modifier and Type	Method and Description
private void	DFS(TreeNode node) A postorder depth first traversal, adding nodes to the list
boolean	hasMoreElements() any elements left?
TreeNode	nextElement() returns the next element in the list iterator

Methods inherited from class java.lang.Object

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

Field Detail

list

private final ArrayList<TreeNode> list

List of nodes in postorder

iterator

private final ListIterator<TreeNode> iterator

an iterator of the above list

Constructor Detail

TreeBottomUpEnumerator

TreeBottomUpEnumerator(TreeNode root)

constructor: it creates the list of nodes

Parameters:

root - Root of the tree whose elements are to be visited.

Method Detail

hasMoreElements

public boolean hasMoreElements()

any elements left?

Specified by:

hasMoreElements in interface Enumeration<TreeNode>

Returns:

whether there are any elements left

nextElement

public TreeNode nextElement()

returns the next element in the list iterator

Specified by:

nextElement in interface Enumeration<TreeNode>

Returns:

the next element in the list iterator or null

DFS

private void DFS(TreeNode node)

A postorder depth first traversal, adding nodes to the list

Parameters:

node - the node to start at