net.sf.saxon.xpath
public class XPathEvaluator extends Object implements XPath
XPathEvaluator provides a simple API for standalone XPath processing (that is, executing XPath expressions in the absence of an XSLT stylesheet). It is an implementation of the JAXP 1.3 XPath interface, with additional methods provided (a) for backwards compatibility (b) to give extra control over the XPath evaluation, and (c) to support XPath 2.0.
Constructor Summary | |
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XPathEvaluator()
Default constructor. | |
XPathEvaluator(Configuration config)
Construct an XPathEvaluator with a specified configuration. | |
XPathEvaluator(Source source)
Construct an XPathEvaluator to process a particular source document. |
Method Summary | |
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XPathExpression | compile(String expr)
Compile an XPath 2.0 expression |
XPathExpressionImpl | createExpression(String expression)
Prepare an XPath expression for subsequent evaluation. |
List | evaluate(String expression)
Prepare and execute an XPath expression, supplied as a string, and returning the results
as a List. |
Object | evaluate(String expr, Object node, QName qName)
Single-shot method to compile and execute an XPath 2.0 expression. |
String | evaluate(String expr, Object node)
Single-shot method to compile an execute an XPath 2.0 expression, returning
the result as a string. |
Object | evaluate(String expr, InputSource inputSource, QName qName)
Single-shot method to parse and build a source document, and
compile an execute an XPath 2.0 expression, against that document |
String | evaluate(String expr, InputSource inputSource)
Single-shot method to parse and build a source document, and
compile an execute an XPath 2.0 expression, against that document,
returning the result as a string |
Object | evaluateSingle(String expression)
Prepare and execute an XPath expression, supplied as a string, and returning the first
item in the result. |
NamespaceContext | getNamespaceContext()
Get the namespace context, if one has been set using |
StandaloneContext | getStaticContext()
Get the current static context |
XPathFunctionResolver | getXPathFunctionResolver()
Get the resolver for XPath functions |
XPathVariableResolver | getXPathVariableResolver()
Get the resolver for XPath variables |
void | importSchema(Source source)
Import a schema. |
boolean | isBackwardsCompatible()
Get the value of XPath 1.0 compatibility mode |
static void | main(String[] args)
A simple command-line interface for the XPathEvaluator (not documented).
|
void | reset() |
void | setBackwardsCompatible(boolean compatible)
Set XPath 1.0 compatibility mode on or off (by default, it is false) |
void | setContextNode(NodeInfo node)
Set the context node. |
void | setNamespaceContext(NamespaceContext namespaceContext)
Set the namespace context to be used. |
NodeInfo | setSource(Source source)
Supply the document against which XPath expressions are to be executed. |
void | setStaticContext(StandaloneContext context)
Set the static context for compiling XPath expressions. |
void | setStripSpace(boolean strip)
Indicate whether all whitespace text nodes in the source document are to be
removed. |
void | setXPathFunctionResolver(XPathFunctionResolver xPathFunctionResolver)
Set the resolver for XPath functions |
void | setXPathVariableResolver(XPathVariableResolver xPathVariableResolver)
Set the resolver for XPath variables |
Parameters: config the configuration to be used. If schema-aware XPath expressions are to be used, this must be a SchemaAwareConfiguration.
Parameters: source The source document (or a specific node within it).
Parameters: expr the XPath 2.0 expression to be compiled, as a string
Returns: the compiled form of the expression
Throws: XPathExpressionException if there are any static errors in the expression. Note that references to undeclared variables are not treated as static errors, because variables are not pre-declared using this API.
Parameters: expression The XPath expression to be evaluated, supplied as a string.
Returns: an XPathExpression object representing the prepared expression
Throws: net.sf.saxon.trans.XPathException if the syntax of the expression is wrong, or if it references namespaces, variables, or functions that have not been declared.
Parameters: expression The XPath expression to be evaluated, supplied as a string.
Returns: The results of the expression, as a List. The List represents the sequence
of items returned by the expression. Each item in the list will either be an object
representing a node, or a Java object representing an atomic value.
The types of Java object that may be included in the list, and the XML Schema data types that they
correspond to, are as follows:
Parameters: expr The XPath 2.0 expression to be compiled and executed node The context node for evaluation of the expression qName The type of result required. For details, see XPathExpressionImpl
Returns: the result of evaluating the expression, returned as described in XPathExpressionImpl
Throws: XPathExpressionException if any static or dynamic error occurs in evaluating the expression.
Parameters: expr The XPath 2.0 expression to be compiled and executed node The context node for evaluation of the expression
Returns: the result of evaluating the expression, converted to a string as if by calling the XPath string() function
Throws: XPathExpressionException if any static or dynamic error occurs in evaluating the expression.
Parameters: expr The XPath 2.0 expression to be compiled and executed inputSource The source document: this will be parsed and built into a tree, and the XPath expression will be executed with the root node of the tree as the context node qName The type of result required. For details, see XPathExpressionImpl
Returns: the result of evaluating the expression, returned as described in XPathExpressionImpl
Throws: XPathExpressionException if any static or dynamic error occurs in evaluating the expression.
Parameters: expr The XPath 2.0 expression to be compiled and executed inputSource The source document: this will be parsed and built into a tree, and the XPath expression will be executed with the root node of the tree as the context node
Returns: the result of evaluating the expression, converted to a string as if by calling the XPath string() function
Throws: XPathExpressionException if any static or dynamic error occurs in evaluating the expression.
Parameters: expression The XPath expression to be evaluated, supplied as a string.
Returns: The first item in the sequence returned by the expression. If the expression returns an empty sequence, this method returns null. Otherwise, it returns the first item in the result sequence, represented as a Java object using the same mapping as for the evaluate() method
Returns: the namespace context if set, or null otherwise
Returns: the resolver, if one has been set
Returns: the resolver, if one has been set
Parameters: source A Source object identifying the schema document to be loaded
Throws: net.sf.saxon.type.SchemaException if the schema contained in this document is invalid UnsupportedOperationException if the configuration is not schema-aware
Returns: true if XPath 1.0 compatibility mode is set
Parameters: compatible true if XPath 1.0 compatibility mode is to be set to true, false if it is to be set to false.
Parameters: node The node to be used as the context node. This must be a node within the context document (the document supplied using the setSource() method).
Throws: NullPointerException if the argument is null IllegalArgumentException if the supplied node is not a node in the context document
Parameters: namespaceContext The namespace context
Parameters: source Any javax.xml.transform.Source object representing the document against
which XPath expressions will be executed. Note that a Saxon The Source object supplied also determines the initial setting
of the context item. In most cases the context node will be the root of the supplied document;
however, if a NodeInfo or DOMSource is supplied it can be any node in the document. DocumentInfo
(indeed any NodeInfo
)
can be used as a Source. To use a third-party DOM Document as a source, create an instance of
javax.xml.transform.dom.DOMSource DOMSource
to wrap it.
Returns: the NodeInfo of the start node in the resulting document object.
Parameters: strip True if all whitespace text nodes are to be stripped from the source document, false otherwise. The default if the method is not called is false.
Parameters: xPathFunctionResolver
Parameters: xPathVariableResolver