Class Matches

All Implemented Interfaces:
Serializable, SourceLocator, Container, Expression, InstructionInfoProvider

public class Matches extends SystemFunction
This class implements the matches() function for regular expression matching
See Also:
  • Constructor Details

    • Matches

      public Matches()
  • Method Details

    • simplify

      public Expression simplify(StaticContext env) 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
      Parameters:
      env - the static context
      Returns:
      the simplified expression
      Throws:
      StaticError - if any error is found (e.g. invalid regular expression)
      XPathException - if an error is discovered during expression rewriting
    • 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
    • tryToCompile

      public static RegularExpression tryToCompile(Expression[] args, int patternArg, int flagsArg, StaticContext env) 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 array
      patternArg - the position of the argument containing the regular expression
      flagsArg - 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