Luke/snow
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

feat: OperatorTokenScanner 重构为状态机

Browse Source
This commit is contained in:
Luke 2025-07-01 17:14:40 +08:00
parent dbc3ea0a33
commit 367ae8653e
1 changed files with 30 additions and 26 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

56
src/main/java/org/jcnc/snow/compiler/lexer/scanners/OperatorTokenScanner.java
View File

@ -45,80 +45,84 @@ public class OperatorTokenScanner extends AbstractTokenScanner {
@Override @Override
protected Token scanToken(LexerContext ctx, int line, int col) { protected Token scanToken(LexerContext ctx, int line, int col) {
char c = ctx.advance(); char c = ctx.advance();
String lexeme; String lexeme = String.valueOf(c);
TokenType type; TokenType type = TokenType.UNKNOWN;
// 当前状态
State currentState = State.OPERATOR;
switch (c) { switch (c) {
case '=': case '=':
if (ctx.match('=')) { if (ctx.match('=')) {
lexeme = "=="; lexeme = "==";
type = TokenType.DOUBLE_EQUALS; type = TokenType.DOUBLE_EQUALS;
} else { } else {
lexeme = "="; type = TokenType.EQUALS;
type = TokenType.EQUALS;
} }
break; break;
case '!': case '!':
if (ctx.match('=')) { if (ctx.match('=')) {
lexeme = "!="; lexeme = "!=";
type = TokenType.NOT_EQUALS; type = TokenType.NOT_EQUALS;
} else { } else {
lexeme = "!"; type = TokenType.NOT;
type = TokenType.NOT;
} }
break; break;
case '>': case '>':
if (ctx.match('=')) { if (ctx.match('=')) {
lexeme = ">="; lexeme = ">=";
type = TokenType.GREATER_EQUAL; type = TokenType.GREATER_EQUAL;
} else { } else {
lexeme = ">"; type = TokenType.GREATER_THAN;
type = TokenType.GREATER_THAN;
} }
break; break;
case '<': case '<':
if (ctx.match('=')) { if (ctx.match('=')) {
lexeme = "<="; lexeme = "<=";
type = TokenType.LESS_EQUAL; type = TokenType.LESS_EQUAL;
} else { } else {
lexeme = "<"; type = TokenType.LESS_THAN;
type = TokenType.LESS_THAN;
} }
break; break;
case '%': case '%':
lexeme = "%"; type = TokenType.MODULO;
type = TokenType.MODULO;
break; break;
case '&': case '&':
if (ctx.match('&')) { if (ctx.match('&')) {
lexeme = "&&"; lexeme = "&&";
type = TokenType.AND; type = TokenType.AND;
} else {
lexeme = "&";
type = TokenType.UNKNOWN;
} }
break; break;
case '|': case '|':
if (ctx.match('|')) { if (ctx.match('|')) {
lexeme = "||"; lexeme = "||";
type = TokenType.OR; type = TokenType.OR;
} else {
lexeme = "|";
type = TokenType.UNKNOWN;
} }
break; break;
default: default:
lexeme = String.valueOf(c); currentState = State.UNKNOWN;
type = TokenType.UNKNOWN; break;
}
// 执行完扫描后，重置状态为初始状态
if (currentState != State.UNKNOWN) {
currentState = State.START;
} }
return new Token(type, lexeme, line, col); return new Token(type, lexeme, line, col);
} }
// 定义状态枚举
private enum State {
START, // 初始状态
OPERATOR, // 当前字符是运算符的一部分
UNKNOWN // 无法识别的状态
}
} }