lexparse.java

java语法解释器生成器

  }
  
  void syntaxError(ErrorMessages message, int line) {
    Out.error(scanner.file, message, line, -1);
  }

  void syntaxError(ErrorMessages message, int line, int col) {
    Out.error(scanner.file, message, line, col);
  }


  private boolean check(int type, char c) {
    switch (type) {
      case sym.JLETTERCLASS:
        return Character.isJavaIdentifierStart(c);
        
      case sym.JLETTERDIGITCLASS:
        return Character.isJavaIdentifierPart(c);
        
      case sym.LETTERCLASS:
        return Character.isLetter(c);
        
      case sym.DIGITCLASS:
        return Character.isDigit(c);
        
      case sym.UPPERCLASS: 
        return Character.isUpperCase(c);
        
      case sym.LOWERCLASS: 
        return Character.isLowerCase(c);
        
      default: return false;
    }
  }
  
  private Vector makePreClass(int type) {
    
    Vector result = new Vector();
    
    char c = 0;
    char start = 0;
    char last = charClasses.getMaxCharCode();
    
    boolean prev, current;
    
    prev = check(type,'\u0000');
    
    for (c = 1; c < last; c++) {
      
      current = check(type,c);
      
      if (!prev && current) start = c;
      if (prev && !current) {
        result.addElement(new Interval(start, (char)(c-1)));
      }
      
      prev = current;
    }
    
    // the last iteration is moved out of the loop to
    // avoid an endless loop if last == maxCharCode and
    // last+1 == 0
    current = check(type,c);
    
    if (!prev && current) result.addElement(new Interval(c,c));
    if (prev && current)  result.addElement(new Interval(start, c));    
    if (prev && !current) result.addElement(new Interval(start, (char)(c-1)));

    return result;
  }
  
  private RegExp makeRepeat(RegExp r, int n1, int n2, int line, int col) {

    if (n1 <= 0 && n2 <= 0) {
      syntaxError(ErrorMessages.REPEAT_ZERO, line, col);
      return null;
    }

    if (n1 > n2) {
      syntaxError(ErrorMessages.REPEAT_GREATER, line, col);
      return null;
    }
    
    int i;
    RegExp result;    

    if (n1 > 0) {
      result = r;
      n1--; n2--; // we need one concatenation less than the number of expressions to match
    }
    else {
      result = new RegExp1(sym.QUESTION,r);
      n2--;
    }

    for (i = 0; i < n1; i++) 
      result = new RegExp2(sym.CONCAT, result, r);
      
    n2-= n1;  
    for (i = 0; i < n2; i++)
      result = new RegExp2(sym.CONCAT, result, new RegExp1(sym.QUESTION,r));
    
    return result;
  }

  private RegExp makeNL() {
    Vector list = new Vector();
    list.addElement(new Interval('\n','\r'));
    list.addElement(new Interval('\u0085','\u0085'));
    list.addElement(new Interval('\u2028','\u2029'));

	// assumption: line feeds are caseless
    charClasses.makeClass(list, false);
    charClasses.makeClass('\n', false);
    charClasses.makeClass('\r', false);

    RegExp1   c = new RegExp1(sym.CCLASS, list);
    Character n = new Character('\n');
    Character r = new Character('\r');

    return new RegExp2(sym.BAR, 
                       c, 
                       new RegExp2(sym.CONCAT, 
                                   new RegExp1(sym.CHAR, r), 
                                   new RegExp1(sym.CHAR, n)));
  }
  

  private final LexParse parser;

  /** Constructor */
  CUP$LexParse$actions(LexParse parser) {
    this.parser = parser;
  }

  /** Method with the actual generated action code. */
  public final java_cup.runtime.Symbol CUP$LexParse$do_action(
    int                        CUP$LexParse$act_num,
    java_cup.runtime.lr_parser CUP$LexParse$parser,
    java.util.Stack            CUP$LexParse$stack,
    int                        CUP$LexParse$top)
    throws java.lang.Exception
    {
      /* Symbol object for return from actions */
      java_cup.runtime.Symbol CUP$LexParse$result;

      /* select the action based on the action number */
      switch (CUP$LexParse$act_num)
        {
          /*. . . . . . . . . . . . . . . . . . . .*/
          case 74: // preclass ::= LOWERCLASS 
            {
              Vector RESULT =null;
		 RESULT = makePreClass(sym.LOWERCLASS); 
              CUP$LexParse$result = parser.getSymbolFactory().newSymbol("preclass",14, ((java_cup.runtime.Symbol)CUP$LexParse$stack.peek()), ((java_cup.runtime.Symbol)CUP$LexParse$stack.peek()), RESULT);
            }
          return CUP$LexParse$result;

          /*. . . . . . . . . . . . . . . . . . . .*/
          case 73: // preclass ::= UPPERCLASS 
            {
              Vector RESULT =null;
		 RESULT = makePreClass(sym.UPPERCLASS); 
              CUP$LexParse$result = parser.getSymbolFactory().newSymbol("preclass",14, ((java_cup.runtime.Symbol)CUP$LexParse$stack.peek()), ((java_cup.runtime.Symbol)CUP$LexParse$stack.peek()), RESULT);
            }
          return CUP$LexParse$result;

          /*. . . . . . . . . . . . . . . . . . . .*/
          case 72: // preclass ::= DIGITCLASS 
            {
              Vector RESULT =null;
		 RESULT = makePreClass(sym.DIGITCLASS); 
              CUP$LexParse$result = parser.getSymbolFactory().newSymbol("preclass",14, ((java_cup.runtime.Symbol)CUP$LexParse$stack.peek()), ((java_cup.runtime.Symbol)CUP$LexParse$stack.peek()), RESULT);
            }
          return CUP$LexParse$result;

          /*. . . . . . . . . . . . . . . . . . . .*/
          case 71: // preclass ::= LETTERCLASS 
            {
              Vector RESULT =null;
		 RESULT = makePreClass(sym.LETTERCLASS); 
              CUP$LexParse$result = parser.getSymbolFactory().newSymbol("preclass",14, ((java_cup.runtime.Symbol)CUP$LexParse$stack.peek()), ((java_cup.runtime.Symbol)CUP$LexParse$stack.peek()), RESULT);
            }
          return CUP$LexParse$result;

          /*. . . . . . . . . . . . . . . . . . . .*/
          case 70: // preclass ::= JLETTERDIGITCLASS 
            {
              Vector RESULT =null;
		 RESULT = makePreClass(sym.JLETTERDIGITCLASS); 
              CUP$LexParse$result = parser.getSymbolFactory().newSymbol("preclass",14, ((java_cup.runtime.Symbol)CUP$LexParse$stack.peek()), ((java_cup.runtime.Symbol)CUP$LexParse$stack.peek()), RESULT);
            }
          return CUP$LexParse$result;

          /*. . . . . . . . . . . . . . . . . . . .*/
          case 69: // preclass ::= JLETTERCLASS 
            {
              Vector RESULT =null;
		 RESULT = makePreClass(sym.JLETTERCLASS); 
              CUP$LexParse$result = parser.getSymbolFactory().newSymbol("preclass",14, ((java_cup.runtime.Symbol)CUP$LexParse$stack.peek()), ((java_cup.runtime.Symbol)CUP$LexParse$stack.peek()), RESULT);
            }
          return CUP$LexParse$result;

          /*. . . . . . . . . . . . . . . . . . . .*/
          case 68: // classcontentelem ::= CHAR 
            {
              Interval RESULT =null;
		int cleft = ((java_cup.runtime.Symbol)CUP$LexParse$stack.peek()).left;
		int cright = ((java_cup.runtime.Symbol)CUP$LexParse$stack.peek()).right;
		Character c = (Character)((java_cup.runtime.Symbol) CUP$LexParse$stack.peek()).value;
		 RESULT = new Interval(c.charValue(), c.charValue()); 
              CUP$LexParse$result = parser.getSymbolFactory().newSymbol("classcontentelem",10, ((java_cup.runtime.Symbol)CUP$LexParse$stack.peek()), ((java_cup.runtime.Symbol)CUP$LexParse$stack.peek()), RESULT);
            }
          return CUP$LexParse$result;

          /*. . . . . . . . . . . . . . . . . . . .*/
          case 67: // classcontentelem ::= CHAR DASH CHAR 
            {
              Interval RESULT =null;
		int c1left = ((java_cup.runtime.Symbol)CUP$LexParse$stack.elementAt(CUP$LexParse$top-2)).left;
		int c1right = ((java_cup.runtime.Symbol)CUP$LexParse$stack.elementAt(CUP$LexParse$top-2)).right;
		Character c1 = (Character)((java_cup.runtime.Symbol) CUP$LexParse$stack.elementAt(CUP$LexParse$top-2)).value;
		int c2left = ((java_cup.runtime.Symbol)CUP$LexParse$stack.peek()).left;
		int c2right = ((java_cup.runtime.Symbol)CUP$LexParse$stack.peek()).right;
		Character c2 = (Character)((java_cup.runtime.Symbol) CUP$LexParse$stack.peek()).value;
		 RESULT = new Interval(c1.charValue(), c2.charValue()); 
              CUP$LexParse$result = parser.getSymbolFactory().newSymbol("classcontentelem",10, ((java_cup.runtime.Symbol)CUP$LexParse$stack.elementAt(CUP$LexParse$top-2)), ((java_cup.runtime.Symbol)CUP$LexParse$stack.peek()), RESULT);
            }
          return CUP$LexParse$result;

          /*. . . . . . . . . . . . . . . . . . . .*/
          case 66: // classcontent ::= MACROUSE 
            {
              Vector RESULT =null;
		int identleft = ((java_cup.runtime.Symbol)CUP$LexParse$stack.peek()).left;
		int identright = ((java_cup.runtime.Symbol)CUP$LexParse$stack.peek()).right;
		String ident = (String)((java_cup.runtime.Symbol) CUP$LexParse$stack.peek()).value;
		 
                     syntaxError(ErrorMessages.CHARCLASS_MACRO, identleft, identright);
                   
              CUP$LexParse$result = parser.getSymbolFactory().newSymbol("classcontent",13, ((java_cup.runtime.Symbol)CUP$LexParse$stack.peek()), ((java_cup.runtime.Symbol)CUP$LexParse$stack.peek()), RESULT);
            }
          return CUP$LexParse$result;

          /*. . . . . . . . . . . . . . . . . . . .*/
          case 65: // classcontent ::= classcontent MACROUSE