org.apache.xpath.jaxp

Class XPathExpressionImpl

Implemented Interfaces:
javax.xml.xpath.XPathExpression

public class XPathExpressionImpl
extends java.lang.Object
implements javax.xml.xpath.XPathExpression

The XPathExpression interface encapsulates a (compiled) XPath expression.
Version:
$Revision: 1.1 $
Author:
Ramesh Mandava

Method Summary

Object
eval(Object item, QName returnType)
String
evaluate(InputSource source)
Evaluate the compiled XPath expression in the context of the specified InputSource and return the result as a String.

This method calls evaluate(InputSource source, QName returnType) with a returnType of XPathConstants.STRING.

See "Evaluation of XPath Expressions" section of JAXP 1.3 spec for context item evaluation, variable, function and QName resolution and return type conversion.

If source is null, then a NullPointerException is thrown.

Object
evaluate(InputSource source, QName returnType)
Evaluate the compiled XPath expression in the context of the specified InputSource and return the result as the specified type.

This method builds a data model for the InputSource and calls evaluate(Object item, QName returnType) on the resulting document object.

See "Evaluation of XPath Expressions" section of JAXP 1.3 spec for context item evaluation, variable, function and QName resolution and return type conversion.

If returnType is not one of the types defined in XPathConstants, then an IllegalArgumentException is thrown.

If source or returnType is null, then a NullPointerException is thrown.

String
evaluate(Object item)
Evaluate the compiled XPath expression in the specified context and return the result as a String.

This method calls evaluate(Object item, QName returnType) with a returnType of XPathConstants.STRING.

See "Evaluation of XPath Expressions" section of JAXP 1.3 spec for context item evaluation, variable, function and QName resolution and return type conversion.

If a null value is provided for item, an empty document will be used for the context.

Object
evaluate(Object item, QName returnType)
Evaluate the compiled XPath expression in the specified context and return the result as the specified type.

See "Evaluation of XPath Expressions" section of JAXP 1.3 spec for context item evaluation, variable, function and QName resolution and return type conversion.

If returnType is not one of the types defined in XPathConstants, then an IllegalArgumentException is thrown.

If a null value is provided for item, an empty document will be used for the context.

void
setXPath(XPath xpath)

Method Details

eval

public Object eval(Object item,
                   QName returnType)
            throws TransformerException

evaluate

public String evaluate(InputSource source)
            throws XPathExpressionException
Evaluate the compiled XPath expression in the context of the specified InputSource and return the result as a String.

This method calls evaluate(InputSource source, QName returnType) with a returnType of XPathConstants.STRING.

See "Evaluation of XPath Expressions" section of JAXP 1.3 spec for context item evaluation, variable, function and QName resolution and return type conversion.

If source is null, then a NullPointerException is thrown.

Parameters:
source - The InputSource of the document to evaluate over.
Returns:
The String that is the result of evaluating the expression and converting the result to a String.

evaluate

public Object evaluate(InputSource source,
                       QName returnType)
            throws XPathExpressionException
Evaluate the compiled XPath expression in the context of the specified InputSource and return the result as the specified type.

This method builds a data model for the InputSource and calls evaluate(Object item, QName returnType) on the resulting document object.

See "Evaluation of XPath Expressions" section of JAXP 1.3 spec for context item evaluation, variable, function and QName resolution and return type conversion.

If returnType is not one of the types defined in XPathConstants, then an IllegalArgumentException is thrown.

If source or returnType is null, then a NullPointerException is thrown.

Parameters:
source - The InputSource of the document to evaluate over.
returnType - The desired return type.
Returns:
The Object that is the result of evaluating the expression and converting the result to returnType.

evaluate

public String evaluate(Object item)
            throws XPathExpressionException
Evaluate the compiled XPath expression in the specified context and return the result as a String.

This method calls evaluate(Object item, QName returnType) with a returnType of XPathConstants.STRING.

See "Evaluation of XPath Expressions" section of JAXP 1.3 spec for context item evaluation, variable, function and QName resolution and return type conversion.

If a null value is provided for item, an empty document will be used for the context.

Parameters:
item - The starting context (node or node list, for example).
Returns:
The String that is the result of evaluating the expression and converting the result to a String.

evaluate

public Object evaluate(Object item,
                       QName returnType)
            throws XPathExpressionException
Evaluate the compiled XPath expression in the specified context and return the result as the specified type.

See "Evaluation of XPath Expressions" section of JAXP 1.3 spec for context item evaluation, variable, function and QName resolution and return type conversion.

If returnType is not one of the types defined in XPathConstants, then an IllegalArgumentException is thrown.

If a null value is provided for item, an empty document will be used for the context. If returnType is null, then a NullPointerException is thrown.

Parameters:
item - The starting context (node or node list, for example).
returnType - The desired return type.
Returns:
The Object that is the result of evaluating the expression and converting the result to returnType.

setXPath

public void setXPath(XPath xpath)

Copyright B) 2005 Apache XML Project. All Rights Reserved.