net.sourceforge.htmlunit.xpath

Class NodeSet

java.lang.Object

net.sourceforge.htmlunit.xpath.NodeSet

All Implemented Interfaces:

Cloneable, NodeList, org.w3c.dom.traversal.NodeIterator

public class NodeSet
extends Object
implements NodeList, org.w3c.dom.traversal.NodeIterator, Cloneable

The NodeSet class can act as either a NodeVector, NodeList, or NodeIterator. However, in order for it to act as a NodeVector or NodeList, it's required that setShouldCacheNodes(true) be called before the first nextNode() is called, in order that nodes can be added as they are fetched. Derived classes that implement iterators must override runTo(int index), in order that they may run the iteration to the given index.

Note that we directly implement the DOM's NodeIterator interface. We do not emulate all the behavior of the standard NodeIterator. In particular, we do not guarantee to present a "live view" of the document ... but in XSLT, the source document should never be mutated, so this should never be an issue.

Thought: Should NodeSet really implement NodeList and NodeIterator, or should there be specific subclasses of it which do so? The advantage of doing it all here is that all NodeSets will respond to the same calls; the disadvantage is that some of them may return less-than-enlightening results when you do so.

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	m_cacheNodes True if this list is cached.
protected int	m_firstFree Number of nodes in this NodeVector.
protected boolean	m_mutable True if this list can be mutated.
protected int	m_next If this node is being used as an iterator, the next index that nextNode() will return.

Constructor Summary

Constructors

Constructor and Description
NodeSet(int blocksize) Create an empty, using the given block size.

Method Summary

Modifier and Type	Method and Description
void	addElement(Node value) Append a Node onto the vector.
void	addNode(Node n) Add a node to the NodeSet.
Object	clone()
void	detach()
Node	elementAt(int i) Get the nth element.
boolean	getExpandEntityReferences()
org.w3c.dom.traversal.NodeFilter	getFilter()
int	getLength()
Node	getRoot()
int	getWhatToShow()
Node	item(int index)
Node	nextNode()
Node	previousNode()
void	runTo(int index)
int	size()

Methods inherited from class java.lang.Object

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

Field Detail

m_next

protected transient int m_next

If this node is being used as an iterator, the next index that nextNode() will return.

m_mutable

protected final transient boolean m_mutable

True if this list can be mutated.

See Also:

Constant Field Values

m_cacheNodes

protected final transient boolean m_cacheNodes

True if this list is cached.

See Also:

Constant Field Values

m_firstFree

protected int m_firstFree

Number of nodes in this NodeVector.

Constructor Detail

NodeSet

public NodeSet(int blocksize)

Create an empty, using the given block size.

Parameters:

blocksize - Size of blocks to allocate

Method Detail

getRoot

public Node getRoot()

Specified by:

getRoot in interface org.w3c.dom.traversal.NodeIterator

getWhatToShow

public int getWhatToShow()

Specified by:

getWhatToShow in interface org.w3c.dom.traversal.NodeIterator

getFilter

public org.w3c.dom.traversal.NodeFilter getFilter()

Specified by:

getFilter in interface org.w3c.dom.traversal.NodeIterator

getExpandEntityReferences

public boolean getExpandEntityReferences()

Specified by:

getExpandEntityReferences in interface org.w3c.dom.traversal.NodeIterator

nextNode

public Node nextNode()
              throws DOMException

Specified by:

nextNode in interface org.w3c.dom.traversal.NodeIterator

Throws:

DOMException

previousNode

public Node previousNode()
                  throws DOMException

Specified by:

previousNode in interface org.w3c.dom.traversal.NodeIterator

Throws:

DOMException

detach

public void detach()

Specified by:

detach in interface org.w3c.dom.traversal.NodeIterator

runTo

public void runTo(int index)

item

public Node item(int index)

Specified by:

item in interface NodeList

getLength

public int getLength()

Specified by:

getLength in interface NodeList

addNode

public void addNode(Node n)

Add a node to the NodeSet. Not all types of NodeSets support this operation

Parameters:

n - Node to be added

Throws:

RuntimeException - thrown if this NodeSet is not of a mutable type.

clone

public Object clone()
             throws CloneNotSupportedException

Overrides:

clone in class Object

Throws:

CloneNotSupportedException

size

public int size()

addElement

public void addElement(Node value)

Append a Node onto the vector.

Parameters:

value - Node to add to the vector

elementAt

public Node elementAt(int i)

Get the nth element.

Parameters:

i - Index of node to get

Returns:

Node at specified index