Class SemCheck

java.lang.Object
jflex.core.SemCheck
public final class SemCheck extends Object
Performs simple semantic analysis on regular expressions.
Version:
JFlex 1.9.1

  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    private
    SemCheck()
    Prevent instantiation of static-only class

  • Method Summary

    Modifier and Type
    Method
    Description
    static void
    check(RegExps rs, File f)
    Performs semantic analysis for all expressions.
    static boolean
    isFiniteChoice(RegExp re)
    Returns true iff the expression is a finite choice of fixed length expressions.
    static int
    length(RegExp re)
    Returns length if expression has fixed length, -1 otherwise.
    static boolean
    maybeEmtpy(RegExp re)
    Checks if the expression potentially matches the empty string.

    Methods inherited from class Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • SemCheck

      private SemCheck()
      Prevent instantiation of static-only class

  • Method Details

    • check

      public static void check(RegExps rs, File f)
      Performs semantic analysis for all expressions.

      Currently checks for empty expressions only.

      Parameters:
      rs - the reg exps to be checked
      f - the spec file containing the rules

    • maybeEmtpy

      public static boolean maybeEmtpy(RegExp re)
      Checks if the expression potentially matches the empty string.
      Parameters:
      re - a RegExp object.
      Returns:
      a boolean.

    • length

      public static int length(RegExp re)
      Returns length if expression has fixed length, -1 otherwise.

      Negation operators are treated as always variable length.

      Parameters:
      re - a RegExp object.
      Returns:
      a int.

    • isFiniteChoice

      public static boolean isFiniteChoice(RegExp re)
      Returns true iff the expression is a finite choice of fixed length expressions.

      Negation operators are treated as always variable length.

      Parameters:
      re - a RegExp object.
      Returns:
      a boolean.