resyntax.java

gcc的组建

  public static final RESyntax RE_SYNTAX_POSIX_EGREP;

  /**
   * Predefined syntax.
   * Emulates POSIX extended regular expression support.
   */
  public static final RESyntax RE_SYNTAX_POSIX_EXTENDED;

  /**
   * Predefined syntax.
   * Emulates POSIX basic minimal regular expressions.
   */
  public static final RESyntax RE_SYNTAX_POSIX_MINIMAL_BASIC;

  /**
   * Predefined syntax.
   * Emulates POSIX extended minimal regular expressions.
   */
  public static final RESyntax RE_SYNTAX_POSIX_MINIMAL_EXTENDED;

  /**
   * Predefined syntax.
   * Emulates regular expression support in the sed utility.
   */
  public static final RESyntax RE_SYNTAX_SED;

  /**
   * Predefined syntax.
   * Emulates regular expression support in Larry Wall's perl, version 4,
   */
  public static final RESyntax RE_SYNTAX_PERL4;

  /**
   * Predefined syntax.
   * Emulates regular expression support in Larry Wall's perl, version 4,
   * using single line mode (/s modifier).
   */
  public static final RESyntax RE_SYNTAX_PERL4_S; // single line mode (/s)

  /**
   * Predefined syntax.
   * Emulates regular expression support in Larry Wall's perl, version 5.
   */
  public static final RESyntax RE_SYNTAX_PERL5;  

  /**
   * Predefined syntax.
   * Emulates regular expression support in Larry Wall's perl, version 5,
   * using single line mode (/s modifier).
   */
  public static final RESyntax RE_SYNTAX_PERL5_S;

    /**
     * Predefined syntax.
     * Emulates regular expression support in Java 1.4's java.util.regex
     * package.
     */
    public static final RESyntax RE_SYNTAX_JAVA_1_4;

  static {
      // Define syntaxes
      
      RE_SYNTAX_EMACS = new RESyntax().makeFinal();
      
      RESyntax RE_SYNTAX_POSIX_COMMON = new RESyntax()
	  .set(RE_CHAR_CLASSES)
	  .set(RE_DOT_NEWLINE)
	  .set(RE_DOT_NOT_NULL)
	  .set(RE_INTERVALS)
	  .set(RE_NO_EMPTY_RANGES)
	  .makeFinal();
      
      RE_SYNTAX_POSIX_BASIC = new RESyntax(RE_SYNTAX_POSIX_COMMON)
	  .set(RE_BK_PLUS_QM)
	  .makeFinal();
      
      RE_SYNTAX_POSIX_EXTENDED = new RESyntax(RE_SYNTAX_POSIX_COMMON)
	  .set(RE_CONTEXT_INDEP_ANCHORS)
	  .set(RE_CONTEXT_INDEP_OPS)
	  .set(RE_NO_BK_BRACES)
	  .set(RE_NO_BK_PARENS)
	  .set(RE_NO_BK_VBAR)
	  .set(RE_UNMATCHED_RIGHT_PAREN_ORD)
	  .makeFinal();

      RE_SYNTAX_AWK = new RESyntax()
	  .set(RE_BACKSLASH_ESCAPE_IN_LISTS)
	  .set(RE_DOT_NOT_NULL)
	  .set(RE_NO_BK_PARENS)
	  .set(RE_NO_BK_REFS)
	  .set(RE_NO_BK_VBAR)
	  .set(RE_NO_EMPTY_RANGES)
	  .set(RE_UNMATCHED_RIGHT_PAREN_ORD)
	  .makeFinal();
      
      RE_SYNTAX_POSIX_AWK = new RESyntax(RE_SYNTAX_POSIX_EXTENDED)
	  .set(RE_BACKSLASH_ESCAPE_IN_LISTS)
	  .makeFinal();
      
      RE_SYNTAX_GREP = new RESyntax()
	  .set(RE_BK_PLUS_QM)
	  .set(RE_CHAR_CLASSES)
	  .set(RE_HAT_LISTS_NOT_NEWLINE)
	  .set(RE_INTERVALS)
	  .set(RE_NEWLINE_ALT)
	  .makeFinal();
      
      RE_SYNTAX_EGREP = new RESyntax()
	  .set(RE_CHAR_CLASSES)
	  .set(RE_CONTEXT_INDEP_ANCHORS)
	  .set(RE_CONTEXT_INDEP_OPS)
	  .set(RE_HAT_LISTS_NOT_NEWLINE)
	  .set(RE_NEWLINE_ALT)
	  .set(RE_NO_BK_PARENS)
	  .set(RE_NO_BK_VBAR)
	  .makeFinal();
    
      RE_SYNTAX_POSIX_EGREP = new RESyntax(RE_SYNTAX_EGREP)
	  .set(RE_INTERVALS)
	  .set(RE_NO_BK_BRACES)
	  .makeFinal();
    
      /* P1003.2/D11.2, section 4.20.7.1, lines 5078ff.  */
    
      RE_SYNTAX_ED = new RESyntax(RE_SYNTAX_POSIX_BASIC)
	  .makeFinal();
    
      RE_SYNTAX_SED = new RESyntax(RE_SYNTAX_POSIX_BASIC)
	  .makeFinal();
      
      RE_SYNTAX_POSIX_MINIMAL_BASIC = new RESyntax(RE_SYNTAX_POSIX_COMMON)
	  .set(RE_LIMITED_OPS)
	  .makeFinal();
      
      /* Differs from RE_SYNTAX_POSIX_EXTENDED in that RE_CONTEXT_INVALID_OPS
	 replaces RE_CONTEXT_INDEP_OPS and RE_NO_BK_REFS is added. */
      
      RE_SYNTAX_POSIX_MINIMAL_EXTENDED = new RESyntax(RE_SYNTAX_POSIX_COMMON)
	  .set(RE_CONTEXT_INDEP_ANCHORS)
	  .set(RE_CONTEXT_INVALID_OPS)
	  .set(RE_NO_BK_BRACES)
	  .set(RE_NO_BK_PARENS)
	  .set(RE_NO_BK_REFS)
	  .set(RE_NO_BK_VBAR)
	  .set(RE_UNMATCHED_RIGHT_PAREN_ORD)
	  .makeFinal();
      
      /* There is no official Perl spec, but here's a "best guess" */
      
      RE_SYNTAX_PERL4 = new RESyntax()
	  .set(RE_BACKSLASH_ESCAPE_IN_LISTS)
	  .set(RE_CONTEXT_INDEP_ANCHORS)
	  .set(RE_CONTEXT_INDEP_OPS)          // except for '{', apparently
	  .set(RE_INTERVALS)
	  .set(RE_NO_BK_BRACES)
	  .set(RE_NO_BK_PARENS)
	  .set(RE_NO_BK_VBAR)
	  .set(RE_NO_EMPTY_RANGES)
	  .set(RE_CHAR_CLASS_ESCAPES)    // \d,\D,\w,\W,\s,\S
	  .makeFinal();
      
      RE_SYNTAX_PERL4_S = new RESyntax(RE_SYNTAX_PERL4)
	  .set(RE_DOT_NEWLINE)
	  .makeFinal();
      
      RE_SYNTAX_PERL5 = new RESyntax(RE_SYNTAX_PERL4)
	  .set(RE_PURE_GROUPING)          // (?:)
	  .set(RE_STINGY_OPS)             // *?,??,+?,{}?
	  .set(RE_LOOKAHEAD)              // (?=)(?!)
	  .set(RE_STRING_ANCHORS)         // \A,\Z
	  .set(RE_CHAR_CLASS_ESC_IN_LISTS)// \d,\D,\w,\W,\s,\S within []
	  .set(RE_COMMENTS)              // (?#)
	  .set(RE_EMBEDDED_FLAGS)         // (?imsx-imsx)
	  .set(RE_OCTAL_CHAR)             // \0377
	  .set(RE_HEX_CHAR)               // \x1b
	  .set(RE_NAMED_PROPERTY)         // \p{prop}, \P{prop}
	  .makeFinal();
      
      RE_SYNTAX_PERL5_S = new RESyntax(RE_SYNTAX_PERL5)
	  .set(RE_DOT_NEWLINE)
	  .makeFinal();

      RE_SYNTAX_JAVA_1_4 = new RESyntax(RE_SYNTAX_PERL5)
	  // XXX
	  .set(RE_POSSESSIVE_OPS)         // *+,?+,++,{}+
	  .set(RE_UNICODE_CHAR)           // \u1234
	  .set(RE_NESTED_CHARCLASS)       // [a-z&&[^p-r]]
	  .makeFinal();
  }

  /**
   * Construct a new syntax object with all bits turned off.
   * This is equivalent to RE_SYNTAX_EMACS.
   */
  public RESyntax() {
    bits = new BitSet(BIT_TOTAL);
  }

    /**
     * Called internally when constructing predefined syntaxes
     * so their interpretation cannot vary.  Conceivably useful
     * for your syntaxes as well.  Causes IllegalAccessError to
     * be thrown if any attempt to modify the syntax is made.
     *
     * @return this object for convenient chaining
     */
    public RESyntax makeFinal() {
	isFinal = true;
	return this;
    }

  /**
   * Construct a new syntax object with all bits set the same 
   * as the other syntax.
   */
  public RESyntax(RESyntax other) {
    bits = (BitSet) other.bits.clone();
  }

  /**
   * Check if a given bit is set in this syntax.
   */
  public boolean get(int index) {
    return bits.get(index);
  }

  /**
   * Set a given bit in this syntax. 
   *
   * @param index the constant (RESyntax.RE_xxx) bit to set.
   * @return a reference to this object for easy chaining.
   */
  public RESyntax set(int index) {
      if (isFinal) throw new IllegalAccessError(SYNTAX_IS_FINAL);
    bits.set(index);
    return this;
  }

  /**
   * Clear a given bit in this syntax. 
   *
   * @param index the constant (RESyntax.RE_xxx) bit to clear.
   * @return a reference to this object for easy chaining.
   */
  public RESyntax clear(int index) {
      if (isFinal) throw new IllegalAccessError(SYNTAX_IS_FINAL);
      bits.clear(index);
      return this;
  }

    /**
     * Changes the line separator string for regular expressions
     * created using this RESyntax.  The default separator is the
     * value returned by the system property "line.separator", which
     * should be correct when reading platform-specific files from a
     * filesystem.  However, many programs may collect input from
     * sources where the line separator is differently specified (for
     * example, in the applet environment, the text box widget
     * interprets line breaks as single-character newlines,
     * regardless of the host platform.
     *
     * Note that setting the line separator to a character or
     * characters that have specific meaning within the current syntax
     * can cause unexpected chronosynclastic infundibula.
     *
     * @return this object for convenient chaining 
     */
    public RESyntax setLineSeparator(String aSeparator) {
	if (isFinal) throw new IllegalAccessError(SYNTAX_IS_FINAL);
	lineSeparator = aSeparator;
	return this;
    }

    /**
     * Returns the currently active line separator string.  The default
     * is the platform-dependent system property "line.separator".
     */
    public String getLineSeparator() {
	return lineSeparator;
    }
}