net.sf.saxon.functions
Class Matches
java.lang.Object
net.sf.saxon.expr.ComputedExpression
net.sf.saxon.expr.FunctionCall
net.sf.saxon.functions.SystemFunction
net.sf.saxon.functions.Matches
- All Implemented Interfaces:
- Expression, Serializable
- public class Matches
- extends SystemFunction
This class implements the matches() function for regular expression matching
- See Also:
- Serialized Form
Methods inherited from class net.sf.saxon.functions.SystemFunction |
addContextDocumentArgument, checkArguments, computeCardinality, display, getDetails, getItemType, getName, getRequiredType, main, makeSystemFunction, useContextItemAsDefault |
Methods inherited from class net.sf.saxon.expr.ComputedExpression |
computeDependencies, computeSpecialProperties, computeStaticProperties, dynamicError, effectiveBooleanValue, evaluateAsString, getCardinality, getDependencies, getIntrinsicDependencies, getLineNumber, getSpecialProperties, iterate, markTailFunctionCalls, setLineNumber, typeError |
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
Matches
public Matches()
simplify
public Expression simplify()
throws XPathException
- Simplify and validate.
This is a pure function so it can be simplified in advance if the arguments are known
- Specified by:
simplify
in interface Expression
- Overrides:
simplify
in class FunctionCall
- Returns:
- the simplified expression
- Throws:
XPathException
- if any error is found (e.g. invalid regular expression)
setFlags
public static int setFlags(String inFlags)
throws XPathException
- Set the Java flags from the supplied XPath flags.
- Parameters:
inFlags
- the flags as a string, e.g. "im"
- Returns:
- the flags as a bit-significant integer
- Throws:
XPathException
- if the supplied value is invalid
tryToCompile
protected static Pattern tryToCompile(Expression[] args,
int patternArg,
int flagsArg)
throws XPathException
- Try to precompile the arguments to the function. This method is shared by
the implementations of the three XPath functions matches(), replace(), and
tokenize().
- Parameters:
args
- the supplied arguments to the function, as an arraypatternArg
- the position of the argument containing the regular expressionflagsArg
- the position of the argument containing the flags
- Returns:
- the compiled regular expression, or null indicating that the information
is not available statically so it cannot be precompiled
- Throws:
XPathException
- if any failure occurs, in particular, if the regular
expression is invalid
evaluateItem
public Item evaluateItem(XPathContext c)
throws XPathException
- Evaluate the matches() function to give a Boolean value.
- Specified by:
evaluateItem
in interface Expression
- Overrides:
evaluateItem
in class ComputedExpression
- Parameters:
c
- The dynamic evaluation context
- Returns:
- the result as a BooleanValue, or null to indicate the empty sequence
- Throws:
XPathException
- on an error