Package net.sf.saxon.regex

Class RECompiler

java.lang.Object
net.sf.saxon.regex.RECompiler
public class RECompiler extends Object
A regular expression compiler class. This class compiles a pattern string into a regular expression program interpretable by the RE evaluator class. The 'recompile' command line tool uses this compiler to pre-compile regular expressions for use with RE. For a description of the syntax accepted by RECompiler and what you can do with regular expressions, see the documentation for the RE matcher class.
See Also:

  • Constructor Details

    • RECompiler

      public RECompiler()
      Constructor. Creates (initially empty) storage for a regular expression program.

  • Method Details

    • setFlags

      public void setFlags(REFlags flags)
      Set the regular expression flags to be used
      Parameters:
      flags - the regular expression flags

    • getWarnings

      public List<String> getWarnings()
      On completion of compilation, get any warnings that were generated
      Returns:
      the list of warning messages

    • makeUnion

      public static CharacterClass makeUnion(CharacterClass p1, CharacterClass p2)
      Make the union of two IntPredicates (matches if p1 matches or p2 matches)
      Parameters:
      p1 - the first
      p2 - the second
      Returns:
      the result

    • makeDifference

      public static CharacterClass makeDifference(CharacterClass p1, CharacterClass p2)
      Make the difference of two IntPredicates (matches if p1 matches and p2 does not match)
      Parameters:
      p1 - the first
      p2 - the second
      Returns:
      the result

    • makeComplement

      public static CharacterClass makeComplement(CharacterClass p1)
      Make the complement of an IntPredicate (matches if p1 does not match)
      Parameters:
      p1 - the operand
      Returns:
      the result

    • compile

      public REProgram compile(UnicodeString pattern) throws RESyntaxException
      Compiles a regular expression pattern into a program runnable by the pattern matcher class 'RE'.
      Parameters:
      pattern - Regular expression pattern to compile (see RECompiler class for details).
      Returns:
      A compiled regular expression program.
      Throws:
      RESyntaxException - Thrown if the regular expression has invalid syntax.
      See Also:

    • noAmbiguity

      public static boolean noAmbiguity(Operation op0, Operation op1, boolean caseBlind, boolean reluctant)
      Determine that there is no ambiguity between two branches, that is, if one of them matches then the other cannot possibly match. (This is for optimization, so it does not have to detect all cases; but if it returns true, then the result must be dependable.)
      Parameters:
      op0 - the first branch
      op1 - the second branch
      caseBlind - true if the "i" flag is in force
      reluctant - true if the first branch is a repeat branch with a reluctant quantifier
      Returns:
      true if it can be established that there is no input sequence that will match both instructions