JavaTM 2 Platform Std. Ed. v1.6.0
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;
}
}
}
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.
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
Copyright 2003 Sun Microsystems, Inc. All rights reserved
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