org.apache.velocity.anakia
Class NodeList

java.lang.Object
  org.apache.velocity.anakia.NodeList

All Implemented Interfaces:

Cloneable, Iterable, Collection, List

public class NodeList
extends Object
implements List, Cloneable

Provides a class for wrapping a list of JDOM objects primarily for use in template engines and other kinds of text transformation tools. It has a toString() method that will output the XML serialized form of the nodes it contains - again focusing on template engine usage, as well as the selectNodes(String) method that helps selecting a different set of nodes starting from the nodes in this list. The class also implements the List interface by simply delegating calls to the contained list (the subList(int, int) method is implemented by delegating to the contained list and wrapping the returned sublist into a NodeList).

Version:

$Id: NodeList.java 191743 2005-06-21 23:22:20Z dlr $

Author:

Attila Szegedi

Constructor Summary

NodeList()
Creates an empty node list.

NodeList(Document document)
Creates a node list that holds a single Document node.

NodeList(Element element)
Creates a node list that holds a single Element node.

NodeList(List nodes)
Creates a node list that holds a list of nodes.

NodeList(List nodes, boolean copy)
Creates a node list that holds a list of nodes.

Method Summary

void	add(int index, Object o)
boolean	add(Object o)
boolean	addAll(Collection c)
boolean	addAll(int index, Collection c)
void	clear()
Object	clone() Returns a NodeList that contains the same nodes as this node list.
boolean	contains(Object o)
boolean	containsAll(Collection c)
boolean	equals(Object o) Tests for equality with another object.
Object	get(int index)
List	getList() Retrieves the underlying list used to store the nodes.
int	hashCode() Returns the hash code of the contained list.
int	indexOf(Object o)
boolean	isEmpty()
Iterator	iterator()
int	lastIndexOf(Object o)
ListIterator	listIterator()
ListIterator	listIterator(int index)
Object	remove(int index)
boolean	remove(Object o)
boolean	removeAll(Collection c)
boolean	retainAll(Collection c)
NodeList	selectNodes(String xpathString) Applies an XPath expression to the node list and returns the resulting node list.
Object	set(int index, Object o)
int	size()
List	subList(int fromIndex, int toIndex)
Object[]	toArray()
Object[]	toArray(Object[] a)
String	toString() This method returns the string resulting from concatenation of string representations of its nodes.

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

NodeList

public NodeList()

Creates an empty node list.

NodeList

public NodeList(Document document)

Creates a node list that holds a single Document node.

NodeList

public NodeList(Element element)

Creates a node list that holds a single Element node.

NodeList

public NodeList(List nodes)

Creates a node list that holds a list of nodes.

Parameters:

nodes - the list of nodes this template should hold. The created template will copy the passed nodes list, so changes to the passed list will not affect the model.

NodeList

public NodeList(List nodes,
                boolean copy)

Creates a node list that holds a list of nodes.

Parameters:

nodes - the list of nodes this template should hold.

copy - if true, the created template will copy the passed nodes list, so changes to the passed list will not affect the model. If false, the model will reference the passed list and will sense changes in it, altough no operations on the list will be synchronized.

Method Detail

getList

public List getList()

Retrieves the underlying list used to store the nodes. Note however, that you can fully use the underlying list through the List interface of this class itself. You would probably access the underlying list only for synchronization purposes.

toString

public String toString()

This method returns the string resulting from concatenation of string representations of its nodes. Each node is rendered using its XML serialization format. This greatly simplifies creating XML-transformation templates, as to output a node contained in variable x as XML fragment, you simply write ${x} in the template (or whatever your template engine uses as its expression syntax).

Overrides:

toString in class Object

clone

public Object clone()
             throws CloneNotSupportedException

Returns a NodeList that contains the same nodes as this node list.

Overrides:

clone in class Object

Throws:

CloneNotSupportedException - if the contained list's class does not have an accessible no-arg constructor.

hashCode

public int hashCode()

Returns the hash code of the contained list.

Specified by:

hashCode in interface Collection

Specified by:

hashCode in interface List

Overrides:

hashCode in class Object

equals

public boolean equals(Object o)

Tests for equality with another object.

Specified by:

equals in interface Collection

Specified by:

equals in interface List

Overrides:

equals in class Object

Parameters:

o - the object to test for equality

Returns:

true if the other object is also a NodeList and their contained List objects evaluate as equals.

selectNodes

public NodeList selectNodes(String xpathString)

Applies an XPath expression to the node list and returns the resulting node list. In order for this method to work, your application must have access to werken.xpath library classes. The implementation does cache the parsed format of XPath expressions in a weak hash map, keyed by the string representation of the XPath expression. As the string object passed as the argument is usually kept in the parsed template, this ensures that each XPath expression is parsed only once during the lifetime of the template that first invoked it.

Parameters:

xpathString - the XPath expression you wish to apply

Returns:

a NodeList representing the nodes that are the result of application of the XPath to the current node list. It can be empty.

add

public boolean add(Object o)

Specified by:

add in interface Collection

Specified by:

add in interface List

add

public void add(int index,
                Object o)

Specified by:

add in interface List

addAll

public boolean addAll(Collection c)

Specified by:

addAll in interface Collection

Specified by:

addAll in interface List

addAll

public boolean addAll(int index,
                      Collection c)

Specified by:

addAll in interface List

clear

public void clear()

Specified by:

clear in interface Collection

Specified by:

clear in interface List

contains

public boolean contains(Object o)

Specified by:

contains in interface Collection

Specified by:

contains in interface List

containsAll

public boolean containsAll(Collection c)

Specified by:

containsAll in interface Collection

Specified by:

containsAll in interface List

get

public Object get(int index)

Specified by:

get in interface List

indexOf

public int indexOf(Object o)

Specified by:

indexOf in interface List

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface Collection

Specified by:

isEmpty in interface List

iterator

public Iterator iterator()

Specified by:

iterator in interface Iterable

Specified by:

iterator in interface Collection

Specified by:

iterator in interface List

lastIndexOf

public int lastIndexOf(Object o)

Specified by:

lastIndexOf in interface List

listIterator

public ListIterator listIterator()

Specified by:

listIterator in interface List

listIterator

public ListIterator listIterator(int index)

Specified by:

listIterator in interface List

remove

public Object remove(int index)

Specified by:

remove in interface List

remove

public boolean remove(Object o)

Specified by:

remove in interface Collection

Specified by:

remove in interface List

removeAll

public boolean removeAll(Collection c)

Specified by:

removeAll in interface Collection

Specified by:

removeAll in interface List

retainAll

public boolean retainAll(Collection c)

Specified by:

retainAll in interface Collection

Specified by:

retainAll in interface List

set

public Object set(int index,
                  Object o)

Specified by:

set in interface List

size

public int size()

Specified by:

size in interface Collection

Specified by:

size in interface List

subList

public List subList(int fromIndex,
                    int toIndex)

Specified by:

subList in interface List

toArray

public Object[] toArray()

Specified by:

toArray in interface Collection

Specified by:

toArray in interface List

toArray

public Object[] toArray(Object[] a)

Specified by:

toArray in interface Collection

Specified by:

toArray in interface List