ElementIterator, as the name suggests, iterates 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:

if next is called before first or current, the root will be returned
next returns null to indicate the end of the list
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 = it.next()) != null) {
             // process element
             System.out.println("elem: " + elem.getName());
         } else {
             break;
         }
     }
}

Nested and Inner Type Summary

Modifier and Type	Class and Description
private static class	ElementIterator.StackItem The `StackItem` class stores the element as well as a child index.

Field Summary

Modifier and Type	Field and Description
private Stack<ElementIterator.StackItem>	elementStack
private Element	root

Access	Constructor and Description
public	ElementIterator(Document a `Document` document) Creates a new `ElementIterator`.
public	ElementIterator(Element the root `Element` root) Creates a new `ElementIterator`.

Method Summary

Modifier and Type	Method and Description
public synchronized Object	Returns: a cloned `ElementIterator` Object clone() Overrides java.lang.Object.clone. Clones the `ElementIterator`.
public Element	Returns: element on top of the stack or `null` if the root element is `null` current() Fetches the current `Element`.
public int	Returns: the depth depth() Fetches the current depth of element tree.
private void	dumpTree() Iterates through the element tree and prints out each element and its attributes.
public Element	Returns: an `Element` first() Fetches the first element.
private Element	getDeepestLeaf(Element parent) Returns the last child of `parent` that is a leaf.
public Element	Returns: the next element or `null` at the end of the list next() Fetches the next `Element`.
public Element	Returns: previous `Element` if available previous() Fetches the previous `Element`.

Inherited from java.lang.Object:: equals finalize getClass hashCode notify notifyAll toString wait wait wait

Field Detail

elementStack	back to summary
private Stack<ElementIterator.StackItem> elementStack

root	back to summary
private Element root

ElementIterator	back to summary
public ElementIterator(Document document) Creates a new `ElementIterator`. The root element is taken to get the default root element of the document. Parameters document:Document a `Document`

ElementIterator	back to summary
public ElementIterator(Element root) Creates a new `ElementIterator`. Parameters root:Element the root `Element`

Method Detail

clone back to summary

clone	back to summary
public synchronized Object clone() Overrides java.lang.Object.clone. Clones the `ElementIterator`. Returns:Object a cloned `ElementIterator` Object

public synchronized Object clone()

Overrides java.lang.Object.clone.

Clones the ElementIterator.

Returns:Object: a cloned ElementIterator Object

current back to summary

current	back to summary
public Element current() Fetches the current `Element`. Returns:Element element on top of the stack or `null` if the root element is `null`

public Element current()

Fetches the current Element.

Returns:Element: element on top of the stack or null if the root element is null

depth	back to summary
public int depth() Fetches the current depth of element tree. Returns:int the depth

depth

back to summary

public int depth()

Fetches the current depth of element tree.

Returns:int: the depth

dumpTree	back to summary
private void dumpTree() Iterates through the element tree and prints out each element and its attributes.

first back to summary

first	back to summary
public Element first() Fetches the first element. Returns:Element an `Element`

public Element first()

Fetches the first element.

Returns:Element: an Element

getDeepestLeaf	back to summary
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.

next back to summary

next	back to summary
public Element next() Fetches the next `Element`. The strategy used to locate the next element is a depth-first search. Returns:Element the next element or `null` at the end of the list

public Element next()

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

Returns:Element: the next element or null at the end of the list

previous back to summary

previous	back to summary
public Element previous() Fetches the previous `Element`. If however the current element is the last element, or the current element is `null`, then `null` is returned. Returns:Element previous `Element` if available

public Element previous()

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

Returns:Element: previous Element if available

javax.swing.text back to summary

private Class ElementIterator.StackItem

Class Inheritance

extends Object
implements Cloneable

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

All Implemented Interfaces

java.lang.Cloneable

The StackItem class stores the element as well as a child index. If the index is -1, then the element represented on the stack is the element itself. Otherwise, the index functions as an index into the vector of children of the element. In this case, the item on the stack represents the "index"th child of the element.

Field Summary

Modifier and Type	Field and Description
pack-priv int	childIndex
pack-priv Element	item

Constructor Summary

Access	Constructor and Description
private	StackItem(Element elem)

Method Summary

Modifier and Type	Method and Description
protected Object	clone() Overrides java.lang.Object.clone. Creates and returns a copy of this object.
private Element	getElement()
private int	getIndex()
private void	incrementIndex()

Inherited from java.lang.Object:: equals finalize getClass hashCode notify notifyAll toString wait wait wait

Field Detail

childIndex	back to summary
pack-priv int childIndex

item	back to summary
pack-priv Element item

Constructor Detail

StackItem	back to summary
private StackItem(Element elem)

Method Detail

clone back to summary

clone	back to summary
protected Object clone() throws CloneNotSupportedException Overrides java.lang.Object.clone. Doc from java.lang.Object.clone. Creates and returns a copy of this object. The precise meaning of "copy" may depend on the class of the object. The general intent is that, for any object `x`, the expression: x.clone() != x will be true, and that the expression: x.clone().getClass() == x.getClass() will be `true`, but these are not absolute requirements. While it is typically the case that: x.clone().equals(x) will be `true`, this is not an absolute requirement. By convention, the returned object should be obtained by calling `super.clone`. If a class and all of its superclasses (except `Object`) obey this convention, it will be the case that `x.clone().getClass() == x.getClass()`. By convention, the object returned by this method should be independent of this object (which is being cloned). To achieve this independence, it may be necessary to modify one or more fields of the object returned by `super.clone` before returning it. Typically, this means copying any mutable objects that comprise the internal "deep structure" of the object being cloned and replacing the references to these objects with references to the copies. If a class contains only primitive fields or references to immutable objects, then it is usually the case that no fields in the object returned by `super.clone` need to be modified. Exceptions CloneNotSupportedException: if the object's class does not support the `Cloneable` interface. Subclasses that override the `clone` method can also throw this exception to indicate that an instance cannot be cloned.

protected Object clone() throws CloneNotSupportedException

Overrides java.lang.Object.clone.

Doc from java.lang.Object.clone.

Creates and returns a copy of this object. The precise meaning of "copy" may depend on the class of the object. The general intent is that, for any object x, the expression:

x.clone() != x

will be true, and that the expression:

x.clone().getClass() == x.getClass()

will be true, but these are not absolute requirements. While it is typically the case that:

x.clone().equals(x)

will be true, this is not an absolute requirement.

By convention, the returned object should be obtained by calling super.clone. If a class and all of its superclasses (except Object) obey this convention, it will be the case that x.clone().getClass() == x.getClass().

By convention, the object returned by this method should be independent of this object (which is being cloned). To achieve this independence, it may be necessary to modify one or more fields of the object returned by super.clone before returning it. Typically, this means copying any mutable objects that comprise the internal "deep structure" of the object being cloned and replacing the references to these objects with references to the copies. If a class contains only primitive fields or references to immutable objects, then it is usually the case that no fields in the object returned by super.clone need to be modified.

Exceptions

CloneNotSupportedException:: if the object's class does not support the Cloneable interface. Subclasses that override the clone method can also throw this exception to indicate that an instance cannot be cloned.

getElement	back to summary
private Element getElement()

getIndex	back to summary
private int getIndex()

incrementIndex	back to summary
private void incrementIndex()

public Class ElementIterator

Nested and Inner Type Summary

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail

private Class ElementIterator.StackItem

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail