public class XPathImpl extends java.lang.Object implements XPath
| Modifier and Type | Method and Description |
|---|---|
XPathExpression |
compile(java.lang.String expression)
Compile an XPath expression for later evaluation.
|
java.lang.String |
evaluate(java.lang.String expression,
InputSource source)
Evaluate an XPath expression in the context of the specified
InputSource
and return the result as a String. |
java.lang.Object |
evaluate(java.lang.String expression,
InputSource source,
QName returnType)
Evaluate an XPath expression in the context of the specified
InputSource
and return the result as the specified type. |
java.lang.String |
evaluate(java.lang.String expression,
java.lang.Object item)
Evaluate an XPath expression in the specified context and return the result as a
String. |
java.lang.Object |
evaluate(java.lang.String expression,
java.lang.Object item,
QName returnType)
Evaluate an
XPath expression in the specified context and return the result as the specified type. |
NamespaceContext |
getNamespaceContext()
Returns the current namespace context.
|
XPathFunctionResolver |
getXPathFunctionResolver()
Returns the current function resolver.
|
XPathVariableResolver |
getXPathVariableResolver()
Returns the current variable resolver.
|
void |
reset()
Reset this
XPath to its original configuration. |
void |
setNamespaceContext(NamespaceContext nsContext)
Establishes a namespace context.
|
void |
setXPathFunctionResolver(XPathFunctionResolver resolver)
Establishes a function resolver.
|
void |
setXPathVariableResolver(XPathVariableResolver resolver)
Establishes a variable resolver.
|
public void setXPathVariableResolver(XPathVariableResolver resolver)
Establishes a variable resolver.
setXPathVariableResolver in interface XPathresolver - Variable Resolverpublic XPathVariableResolver getXPathVariableResolver()
Returns the current variable resolver.
getXPathVariableResolver in interface XPathpublic void setXPathFunctionResolver(XPathFunctionResolver resolver)
Establishes a function resolver.
setXPathFunctionResolver in interface XPathresolver - XPath function resolverpublic XPathFunctionResolver getXPathFunctionResolver()
Returns the current function resolver.
getXPathFunctionResolver in interface XPathpublic void setNamespaceContext(NamespaceContext nsContext)
Establishes a namespace context.
setNamespaceContext in interface XPathnsContext - Namespace context to usepublic NamespaceContext getNamespaceContext()
Returns the current namespace context.
getNamespaceContext in interface XPathpublic java.lang.Object evaluate(java.lang.String expression,
java.lang.Object item,
QName returnType)
throws XPathExpressionException
Evaluate an 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 (
NUMBER,
STRING,
BOOLEAN,
NODE or
NODESET)
then an IllegalArgumentException is thrown.
If a null value is provided for
item, an empty document will be used for the
context.
If expression or returnType is null, then a
NullPointerException is thrown.
evaluate in interface XPathexpression - The XPath expression.item - The starting context (node or node list, for example).returnType - The desired return type.Object of returnType.XPathExpressionException - If expression cannot be evaluated.java.lang.IllegalArgumentException - If returnType is not one of the types defined in XPathConstants.java.lang.NullPointerException - If expression or returnType is null.public java.lang.String evaluate(java.lang.String expression,
java.lang.Object item)
throws XPathExpressionException
Evaluate an XPath expression in the specified context and return the result as a String.
This method calls evaluate(String expression, Object item, QName returnType) with a returnType of
XPathConstants.STRING.
See "Evaluation of XPath Expressions" 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.
If expression is null, then a NullPointerException is thrown.
evaluate in interface XPathexpression - The XPath expression.item - The starting context (node or node list, for example).String that is the result of evaluating the expression and
converting the result to a String.XPathExpressionException - If expression cannot be evaluated.java.lang.NullPointerException - If expression is null.public XPathExpression compile(java.lang.String expression) throws XPathExpressionException
Compile an XPath expression for later evaluation.
If expression contains any XPathFunctions,
they must be available via the XPathFunctionResolver.
An XPathExpressionException will be thrown if the XPathFunction
cannot be resovled with the XPathFunctionResolver.
If expression is null, a NullPointerException is thrown.
compile in interface XPathexpression - The XPath expression.XPathExpressionException - If expression cannot be compiled.java.lang.NullPointerException - If expression is null.public java.lang.Object evaluate(java.lang.String expression,
InputSource source,
QName returnType)
throws XPathExpressionException
Evaluate an 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(String expression, 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 expression, source or returnType is null,
then a NullPointerException is thrown.
evaluate in interface XPathexpression - The XPath expression.source - The input source of the document to evaluate over.returnType - The desired return type.Object that encapsulates the result of evaluating the expression.XPathExpressionException - If expression cannot be evaluated.java.lang.IllegalArgumentException - If returnType is not one of the types defined in XPathConstants.java.lang.NullPointerException - If expression, source or returnType
is null.public java.lang.String evaluate(java.lang.String expression,
InputSource source)
throws XPathExpressionException
Evaluate an XPath expression in the context of the specified InputSource
and return the result as a String.
This method calls evaluate(String expression, 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 expression or source is null,
then a NullPointerException is thrown.
evaluate in interface XPathexpression - The XPath expression.source - The InputSource of the document to evaluate over.String that is the result of evaluating the expression and
converting the result to a String.XPathExpressionException - If expression cannot be evaluated.java.lang.NullPointerException - If expression or source is null.public void reset()
Reset this XPath to its original configuration.
XPath is reset to the same state as when it was created with
XPathFactory#newXPath().
reset() is designed to allow the reuse of existing XPaths
thus saving resources associated with the creation of new XPaths.
The reset XPath is not guaranteed to have the same
XPathFunctionResolver, XPathVariableResolver
or NamespaceContext Objects, e.g. Object.equals(Object obj).
It is guaranteed to have a functionally equal XPathFunctionResolver,
XPathVariableResolver
and NamespaceContext.
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