org.apache.xpath.domapi
Class XPathExpressionImpl

java.lang.Object
  org.apache.xpath.domapi.XPathExpressionImpl

public class XPathExpressionImpl

extends Object

The class provides an implementation of XPathExpression according to the DOM L3 XPath Specification, Working Draft 28, March 2002.

See also the Document Object Model (DOM) Level 3 XPath Specification.

The XPathExpression interface represents a parsed and resolved XPath expression.

See Also:

org.w3c.dom.xpath.XPathExpression

Field Summary

private org.w3c.dom.Document	m_doc The document to be searched to parallel the case where the XPathEvaluator is obtained by casting a Document.
private PrefixResolver	m_resolver
private XPath	m_xpath The xpath object that this expression wraps

Constructor Summary

(package private)

XPathExpressionImpl(XPath xpath, org.w3c.dom.Document doc) Constructor for XPathExpressionImpl.

Method Summary

Object

evaluate(org.w3c.dom.Node contextNode, short type, Object result) This method provides an implementation XPathResult.evaluate according to the DOM L3 XPath Specification, Working Draft 28, March 2002.

Methods inherited from class java.lang.Object

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

Field Detail

m_resolver

private PrefixResolver m_resolver

m_xpath

private XPath m_xpath

The xpath object that this expression wraps

m_doc

private org.w3c.dom.Document m_doc

The document to be searched to parallel the case where the XPathEvaluator is obtained by casting a Document.

Constructor Detail

XPathExpressionImpl

XPathExpressionImpl(XPath xpath,
                    org.w3c.dom.Document doc)

Constructor for XPathExpressionImpl.

Parameters:

xpath - The wrapped XPath object.

doc - The document to be searched, to parallel the case where'' the XPathEvaluator is obtained by casting the document.

Method Detail

evaluate

public Object evaluate(org.w3c.dom.Node contextNode,
                       short type,
                       Object result)
                throws XPathException,
                       org.w3c.dom.DOMException

This method provides an implementation XPathResult.evaluate according to the DOM L3 XPath Specification, Working Draft 28, March 2002.

See also the Document Object Model (DOM) Level 3 XPath Specification.

Evaluates this XPath expression and returns a result.

Parameters:

contextNode - The context is context node for the evaluation of this XPath expression.If the XPathEvaluator was obtained by casting the Document then this must be owned by the same document and must be a Document, Element, Attribute, Text, CDATASection, Comment, ProcessingInstruction, or XPathNamespace node.If the context node is a Text or a CDATASection, then the context is interpreted as the whole logical text node as seen by XPath, unless the node is empty in which case it may not serve as the XPath context.

type - If a specific type is specified, then the result will be coerced to return the specified type relying on XPath conversions and fail if the desired coercion is not possible. This must be one of the type codes of XPathResult.

result - The result specifies a specific result object which may be reused and returned by this method. If this is specified as nullor the implementation does not reuse the specified result, a new result object will be constructed and returned.For XPath 1.0 results, this object will be of type XPathResult.

Returns:

The result of the evaluation of the XPath expression.For XPath 1.0 results, this object will be of type XPathResult.

Throws:

XPathException - TYPE_ERR: Raised if the result cannot be converted to return the specified type.

org.w3c.dom.DOMException - WRONG_DOCUMENT_ERR: The Node is from a document that is not supported by the XPathEvaluator that created this XPathExpression.
NOT_SUPPORTED_ERR: The Node is not a type permitted as an XPath context node.

See Also:

org.w3c.dom.xpath.XPathExpression#evaluate(Node, short, XPathResult)