org.springframework.xml.xpath
Interface XPathExpression

public interface XPathExpression

Defines the contract for a precompiled XPath expression. Concrete instances can be obtained through the XPathExpressionFactory.

Implementations of this interface are precompiled, and thus faster, but less flexible, than the XPath expressions used by XPathOperations implementations.

Since:

1.0.0

Author:

Arjen Poutsma

Method Summary

List	evaluate(Node node, NodeMapper nodeMapper) Evaluates the given expression, mapping each result Node objects to a Java object via a NodeMapper.
boolean	evaluateAsBoolean(Node node) Evaluates the given expression as a boolean.
Node	evaluateAsNode(Node node) Evaluates the given expression as a Node.
List	evaluateAsNodeList(Node node) Evaluates the given expression, and returns all Node objects that conform to it.
double	evaluateAsNumber(Node node) Evaluates the given expression as a number (double).
Object	evaluateAsObject(Node node, NodeMapper nodeMapper) Evaluates the given expression, mapping a single Node result to a Java object via a NodeMapper.
String	evaluateAsString(Node node) Evaluates the given expression as a String.

Method Detail

evaluateAsBoolean

boolean evaluateAsBoolean(Node node)
                          throws XPathException

Evaluates the given expression as a boolean. Returns the boolean evaluation of the expression, or false if it is invalid.

Parameters:

node - the starting point

Returns:

the result of the evaluation

Throws:

XPathException - in case of XPath errors

See Also:

XPath specification

evaluateAsNode

Node evaluateAsNode(Node node)
                    throws XPathException

Evaluates the given expression as a Node. Returns the evaluation of the expression, or null if it is invalid.

Parameters:

node - the starting point

Returns:

the result of the evaluation

Throws:

XPathException - in case of XPath errors

See Also:

XPath specification

evaluateAsNodeList

List evaluateAsNodeList(Node node)
                        throws XPathException

Evaluates the given expression, and returns all Node objects that conform to it. Returns an empty list if no result could be found.

Parameters:

node - the starting point

Returns:

a list of Nodes that are selected by the expression

Throws:

XPathException - in case of XPath errors

See Also:

XPath specification

evaluateAsNumber

double evaluateAsNumber(Node node)
                        throws XPathException

Evaluates the given expression as a number (double). Returns the numeric evaluation of the expression, or Double.NaN if it is invalid.

Parameters:

node - the starting point

Returns:

the result of the evaluation

Throws:

XPathException - in case of XPath errors

See Also:

XPath specification

evaluateAsString

String evaluateAsString(Node node)
                        throws XPathException

Evaluates the given expression as a String. Returns null if no result could be found.

Parameters:

node - the starting point

Returns:

the result of the evaluation

Throws:

XPathException - in case of XPath errors

See Also:

XPath specification

evaluateAsObject

Object evaluateAsObject(Node node,
                        NodeMapper nodeMapper)
                        throws XPathException

Evaluates the given expression, mapping a single Node result to a Java object via a NodeMapper.

Parameters:

node - the starting point

nodeMapper - object that will map one object per node

Returns:

the single mapped object

Throws:

XPathException - in case of XPath errors

See Also:

XPath specification

evaluate

List evaluate(Node node,
              NodeMapper nodeMapper)
              throws XPathException

Evaluates the given expression, mapping each result Node objects to a Java object via a NodeMapper.

Parameters:

node - the starting point

nodeMapper - object that will map one object per node

Returns:

the result list, containing mapped objects

Throws:

XPathException - in case of XPath errors

See Also:

XPath specification