org.exolab.adaptx.xpath

Class XPathNode

public abstract class XPathNode extends Object implements Serializable

Abstract class representing a node in a document tree, on which XPath expressions can be evaluated. This abstract class provides all the services required by XPath, and enables multiple implementations to exist. It does not make use of iterators or traversals, but assumes double-linked lists are used to maintain node lists.

Version: $Revision: 3633 $

Author: Keith Visco Assaf Arkin

Field Summary
static intATTRIBUTE
Node is an attribute.
static intCOMMENT
Node is a comment.
static intELEMENT
Node is an element.
static intNAMESPACE
Node is a namespace node.
static intPI
Node is a processing instruction.
static intROOT
Node is a root node.
static intTEXT
Node is a text node.
Method Summary
abstract StringgetAttribute(String uri, String local)
Returns the value of the named attribute, or null if the node has no such attribute.
abstract XPathNodegetFirstAttribute()
Returns the first in a list of attribute nodes, or null if the node has no attributes.
abstract XPathNodegetFirstChild()
Returns the first child node of this node, or null if the node has no children.
abstract XPathNodegetFirstNamespace()
Returns the first in a list of namespace nodes, or null if the node has no namespaces.
abstract StringgetLocalName()
Returns the local name of the node.
abstract StringgetNamespacePrefix(String uri)
Returns the namespace prefix associated with this namespace URI, as defined in the context of this node.
abstract StringgetNamespaceURI()
Returns the namespace URI the node.
abstract StringgetNamespaceURI(String prefix)
Returns the namespace URI associated with this namespace prefix, as defined in the context of this node.
abstract XPathNodegetNext()
Returns the next sibling node in document order, or null if this node is the last node.
abstract intgetNodeType()
Returns the type of this node.
abstract XPathNodegetParentNode()
Returns the parent node, or null if the node has no parent.
abstract XPathNodegetPrevious()
Returns the previous sibling node in document order, or null if this node is the first node.
abstract XPathNodegetRootNode()
Returns the root node.
abstract StringgetStringValue()
Returns the string value of the node.
abstract booleanhasChildNodes()
Returns true if this node has any child nodes.

Field Detail

ATTRIBUTE

public static final int ATTRIBUTE
Node is an attribute.

COMMENT

public static final int COMMENT
Node is a comment.

ELEMENT

public static final int ELEMENT
Node is an element.

NAMESPACE

public static final int NAMESPACE
Node is a namespace node.

PI

public static final int PI
Node is a processing instruction.

ROOT

public static final int ROOT
Node is a root node.

TEXT

public static final int TEXT
Node is a text node.

Method Detail

getAttribute

public abstract String getAttribute(String uri, String local)
Returns the value of the named attribute, or null if the node has no such attribute. If the argument uri is null, the node's namespace URI will be used. This method is valid only for the element node.

Parameters: uri The attribute's namespace URI, or null local The attribute's local name

Returns: The attribute's value, or null if no such attribute exists

getFirstAttribute

public abstract XPathNode getFirstAttribute()
Returns the first in a list of attribute nodes, or null if the node has no attributes. This method is valid only for the element node.

Returns: The first in a list of attribute nodes, or null

getFirstChild

public abstract XPathNode getFirstChild()
Returns the first child node of this node, or null if the node has no children. Child nodes are only returned for an element or root node.

Returns: The first child node of this node, or null

getFirstNamespace

public abstract XPathNode getFirstNamespace()
Returns the first in a list of namespace nodes, or null if the node has no namespaces. This method is valid only for the element node.

Returns: The first in a list of namespace nodes, or null

getLocalName

public abstract String getLocalName()
Returns the local name of the node. Returns the local name of an element or attribute, the prefix of a namespace node, the target of a processing instruction, or null for all other node types.

Returns: The local name of the node, or null if the node has no name

getNamespacePrefix

public abstract String getNamespacePrefix(String uri)
Returns the namespace prefix associated with this namespace URI, as defined in the context of this node. Returns null if no prefix is defined for this namespace URI. Returns an empty string if the default prefix is associated with this namespace URI. This method is valid only for element nodes.

Parameters: uri The namespace URI

Returns: The namespace prefix, or null

getNamespaceURI

public abstract String getNamespaceURI()
Returns the namespace URI the node. Returns the namespace URI of an element, attribute or namespace node, or null for all other node types.

Returns: The namespace URI of the node, or null if the node has no namespace URI

getNamespaceURI

public abstract String getNamespaceURI(String prefix)
Returns the namespace URI associated with this namespace prefix, as defined in the context of this node. Returns null if the prefix is undefined. Returns empty if the prefix is defined and associated with no namespace. This method is valid only for element nodes.

Parameters: prefix The namespace prefix

Returns: The namespace URI, or null

getNext

public abstract XPathNode getNext()
Returns the next sibling node in document order, or null if this node is the last node. This method is value for any node except the root node.

Returns: The next sibling node in document order, or null

getNodeType

public abstract int getNodeType()
Returns the type of this node.

Returns: The type of this node

getParentNode

public abstract XPathNode getParentNode()
Returns the parent node, or null if the node has no parent. This method is valid on all node types except the root node. Attribute and namespace nodes have the element as their parent node.

Returns: The parent node, or null

getPrevious

public abstract XPathNode getPrevious()
Returns the previous sibling node in document order, or null if this node is the first node. This method can is valid for any node except the root node.

Returns: The previous sibling node in document order, or null

getRootNode

public abstract XPathNode getRootNode()
Returns the root node. Note to implementors: This should NOT return null.

Returns: The root node

getStringValue

public abstract String getStringValue()
Returns the string value of the node. The string value of a text node or an attribute node is it's text value. The string value of an element or a root node is the concatenation of the string value of all its child nodes. The string value of a namespace node is its namespace URI. The string value of a processing instruction is the instruction, and the string value of a comment is the comment text.

Returns: The string value of the node

hasChildNodes

public abstract boolean hasChildNodes()
Returns true if this node has any child nodes.

Returns: True if this node has any child nodes.