javax.swing.text
Class ElementIterator

java.lang.Object
  javax.swing.text.ElementIterator

All Implemented Interfaces:

Cloneable

public class ElementIterator

extends Object

implements Cloneable

ElementIterator, as the name suggests, iteratates over the Element tree. The constructor can be invoked with either Document or an Element as an argument. If the constructor is invoked with a Document as an argument then the root of the iteration is the return value of document.getDefaultRootElement(). The iteration happens in a depth-first manner. In terms of how boundary conditions are handled: a) if next() is called before first() or current(), the root will be returned. b) next() returns null to indicate the end of the list. c) previous() returns null when the current element is the root or next() has returned null. The ElementIterator does no locking of the Element tree. This means that it does not track any changes. It is the responsibility of the user of this class, to ensure that no changes happen during element iteration. Simple usage example: public void iterate() { ElementIterator it = new ElementIterator(root); Element elem; while (true) { if ((elem = next()) != null) { // process element System.out.println("elem: " + elem.getName()); } else { break; } } }

Author:

Sunita Mani

Nested Class Summary

private class

ElementIterator.StackItem The StackItem class stores the element as well as a child index.

Field Summary

private Stack	elementStack
private Element	root

Constructor Summary

ElementIterator(Document document)
Creates a new ElementIterator.

ElementIterator(Element root)
Creates a new ElementIterator.

Method Summary

Object	clone() Clones the ElementIterator.
Element	current() Fetches the current Element.
int	depth() Fetches the current depth of element tree.
private void	dumpTree()
Element	first() Fetches the first element.
private Element	getDeepestLeaf(Element parent) Returns the last child of parent that is a leaf.
Element	next() Fetches the next Element.
Element	previous() Fetches the previous Element.

Methods inherited from class java.lang.Object

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

Field Detail

root

private Element root

elementStack

private Stack elementStack

Constructor Detail

ElementIterator

public ElementIterator(Document document)

Creates a new ElementIterator. The root element is taken to get the default root element of the document.

Parameters:

document - a Document.

ElementIterator

public ElementIterator(Element root)

Creates a new ElementIterator.

Parameters:

root - the root Element.

Method Detail

clone

public Object clone()

Clones the ElementIterator.

Overrides:

clone in class Object

Returns:

a cloned ElementIterator Object.

See Also:

Cloneable

first

public Element first()

Fetches the first element.

Returns:

an Element.

depth

public int depth()

Fetches the current depth of element tree.

Returns:

the depth.

current

public Element current()

Fetches the current Element.

Returns:

element on top of the stack or null if the root element is null

next

public Element next()

Fetches the next Element. The strategy used to locate the next element is a depth-first search.

Returns:

the next element or null at the end of the list.

previous

public Element previous()

Fetches the previous Element. If howver the current element is the last element, or the current element is null, then null is returned.

Returns:

previous Element if available

getDeepestLeaf

private Element getDeepestLeaf(Element parent)

Returns the last child of parent that is a leaf. If the last child is a not a leaf, this method is called with the last child.

dumpTree

private void dumpTree()