+++ /dev/null
-// Simple Example Scanner Class
-
-package java_cup.simple_calc;
-
-import java_cup.runtime.Symbol;
-
-public class scanner implements java_cup.runtime.Scanner {
- final java.io.InputStream instream;
-
- public scanner(java.io.InputStream is) throws java.io.IOException {
- instream = is;
- }
- public scanner() throws java.io.IOException { this(System.in); }
-
- /* single lookahead character */
- protected int next_char = -2;
-
- /* advance input by one character */
- protected void advance()
- throws java.io.IOException
- { next_char = instream.read(); }
-
- /* initialize the scanner */
- private void init()
- throws java.io.IOException
- { advance(); }
-
- /* recognize and return the next complete token */
- public Symbol next_token()
- throws java.io.IOException
- {
- if (next_char==-2) init(); // set stuff up first time we are called.
- for (;;)
- switch (next_char)
- {
- case '0': case '1': case '2': case '3': case '4':
- case '5': case '6': case '7': case '8': case '9':
- /* parse a decimal integer */
- int i_val = 0;
- do {
- i_val = i_val * 10 + (next_char - '0');
- advance();
- } while (next_char >= '0' && next_char <= '9');
- return new Symbol(sym.NUMBER, new Integer(i_val));
-
- case ';': advance(); return new Symbol(sym.SEMI);
- case '+': advance(); return new Symbol(sym.PLUS);
- case '-': advance(); return new Symbol(sym.MINUS);
- case '*': advance(); return new Symbol(sym.TIMES);
- case '/': advance(); return new Symbol(sym.DIVIDE);
- case '%': advance(); return new Symbol(sym.MOD);
- case '(': advance(); return new Symbol(sym.LPAREN);
- case ')': advance(); return new Symbol(sym.RPAREN);
-
- case -1: return new Symbol(sym.EOF);
-
- default:
- /* in this simple scanner we just ignore everything else */
- advance();
- break;
- }
- }
-};