コード例 #1
0
ファイル: Scanner.java プロジェクト: brendandahl/j2me.js
 //
 // Advanced the input by one character
 //
 protected void advance() throws java.io.IOException {
   next_char = inp.read();
   switch (next_char) {
     case -1: // EOF
       if (char_num == 0) {
         char_num = -1;
         break;
       }
       next_char = '\n';
       // pass thru
     case '\n': // a new line
       line_num++;
       char_num = 0;
       break;
     default:
       line.append((char) next_char);
       char_num++;
       return;
   }
   line.setLength(0);
 }
コード例 #2
0
ファイル: Scanner.java プロジェクト: brendandahl/j2me.js
  //
  // recognize and return the next complete token
  //
  public token next_token() throws java.io.IOException, jasError {
    token_line_num = line_num;

    for (; ; )
      switch (next_char) {
        case ';': // a comment
        case '\n':
          // return single SEP token (skip multiple newlines
          // interspersed with whitespace or comments)
          skip_empty_lines();
          token_line_num = line_num;
          return new token(sym.SEP);

        case -1: // EOF token
          char_num = -1;
          return new token(sym.EOF);

        case '-':
        case '+':
        case '0':
        case '1':
        case '2':
        case '3':
        case '4':
        case '5':
        case '6':
        case '7':
        case '8':
        case '9':
        case '.': // a number
          {
            int pos = 0;
            do {
              chars[pos] = (char) next_char;
              pos++;
              if (pos == chars_size) chars_expand();
              advance();
            } while (!separator(next_char));

            String str = new String(chars, 0, pos);
            token tok;

            // This catches directives like ".method"
            if ((tok = ReservedWords.get(str)) != null) return tok;

            Number num;
            try {
              num = ScannerUtils.convertNumber(str);
            } catch (NumberFormatException e) {
              if (chars[0] != '.') throw new jasError("Badly formatted number");
              throw new jasError("Unknown directive or badly formed number.");
            }

            if (num instanceof Integer) {
              int_line = line.toString();
              int_line_num = token_line_num;
              int_char_num = char_num;
              return new int_token(sym.Int, num.intValue());
            }
            return new num_token(sym.Num, num);
          }

        case '"': // quoted string
          {
            boolean already = false;
            for (int pos = 0; ; ) {
              if (already) already = false;
              else advance();

              if (next_char == '"') {
                advance(); // skip close quote
                return new str_token(sym.Str, new String(chars, 0, pos));
              }

              if (next_char == -1) throw new jasError("Unterminated string");

              char chval = (char) next_char;

              if (chval == '\\') {
                advance();
                switch (next_char) {
                  case -1:
                    already = true;
                    continue;
                  case 'n':
                    chval = '\n';
                    break;
                  case 'r':
                    chval = '\r';
                    break;
                  case 't':
                    chval = '\t';
                    break;
                  case 'f':
                    chval = '\f';
                    break;
                  case 'b':
                    chval = '\b';
                    break;
                  case '"':
                    chval = '"';
                    break;
                  case '\'':
                    chval = '\'';
                    break;
                  case '\\':
                    chval = '\\';
                    break;

                  case 'u':
                    chval = uniEscape();
                    if (next_char == -1) {
                      already = true;
                      continue;
                    }
                    break;

                  case '0':
                  case '1':
                  case '2':
                  case '3':
                  case '4':
                  case '5':
                  case '6':
                  case '7':
                    {
                      int res = next_char & 7;
                      advance();
                      if (next_char < '0' || next_char > '7') already = true;
                      else {
                        res = res * 8 + (next_char & 7);
                        advance();
                        if (next_char < '0' || next_char > '7') already = true;
                        else {
                          int val = res * 8 + (next_char & 7);
                          if (val >= 0x100) already = true;
                          else res = val;
                        }
                      }
                      chval = (char) res;
                    }
                    break;

                  default:
                    throw new jasError("Bad backslash escape sequence");
                }
              }
              chars[pos] = chval;
              pos++;
              if (pos == chars_size) chars_expand();
            }
          }

        case '\'': // quotation for overloading reserved words
          for (int pos = 0; ; ) {
            advance();
            if (separator(next_char)) throw new jasError("Unterminated ''-enclosed name");
            if (next_char == '\'') {
              if (pos == 0) throw new jasError("Empty ''-enclosed name");
              advance(); // skip close quote
              if (!separator(next_char)) throw new jasError("Not separator after ''-enclosed name");
              return new str_token(sym.Word, new String(chars, 0, pos));
            }
            char chval = (char) next_char;
            if (next_char == '\\') chval = nameEscape();
            chars[pos] = chval;
            pos++;
            if (pos == chars_size) chars_expand();
          }

        case ' ':
        case '\t':
        case '\r': // whitespace
          advance();
          break;

        case '=': // EQUALS token
          advance();
          return new token(sym.EQ);

        case ':': // COLON token
          advance();
          return new token(sym.COLON);

        default:
          {
            // read up until a separatorcharacter
            int pos = 0;
            boolean only_name = false;

            do {
              char chval = (char) next_char;
              if (next_char == '\\') {
                chval = nameEscape();
                only_name = true;
              }
              chars[pos] = chval;
              pos++;
              if (pos == chars_size) chars_expand();
              advance();
            } while (!separator(next_char));
            // convert the byte array into a String
            String str = new String(chars, 0, pos);

            if (!only_name) {
              token tok;

              // Jasmin keyword or directive ?
              if ((tok = ReservedWords.get(str)) != null) return tok;

              // its a JVM instruction ?
              if (InsnInfo.contains(str)) return new str_token(sym.Insn, str);

              if (str.charAt(0) == '$') {
                String s = str.substring(1);
                Object v;
                int n = 10;
                boolean neg = false;
                boolean sign = false;
                switch (s.charAt(0)) {
                  default:
                    break;

                  case '-':
                    neg = true;
                    ;
                  case '+':
                    s = s.substring(1);
                    if (s.startsWith("0x")) {
                      n = 16;
                      s = s.substring(2);
                    }
                    try {
                      n = Integer.parseInt(s, n);
                    } catch (NumberFormatException e) {
                      throw new jasError("Badly relative offset number");
                    }
                    if (neg) n = -n;
                    return new relative_num_token(sym.Relative, n);
                }
                // Perform variable substitution
                if ((v = dict.get(s)) != null) return (token) v;
              } // not begin from '$'
            } // !only_name
            // Unrecognized string token (e.g. a classname)
            return new str_token(sym.Word, str);
          } /* default */
      } /* switch and for */
  }