为什么我的 antlr lexer java 类是“代码太大"? [英] Why my antlr lexer java class is "code too large"?

问题描述

这是 Antlr 中的词法分析器(抱歉文件太长):

This is the lexer in Antlr (sorry for a long file):

lexer grammar SqlServerDialectLexer;
/* T-SQL words */
AND: 'AND';
BIGINT: 'BIGINT';
BIT: 'BIT';
CASE: 'CASE';
CHAR: 'CHAR';
COUNT: 'COUNT';
CREATE: 'CREATE';
CURRENT_TIMESTAMP: 'CURRENT_TIMESTAMP';
DATETIME: 'DATETIME';
DECLARE: 'DECLARE';
ELSE: 'ELSE';
END: 'END';
FLOAT: 'FLOAT';
FROM: 'FROM';
GO: 'GO';
IMAGE: 'IMAGE';
INNER: 'INNER';
INSERT: 'INSERT';
INT: 'INT';
INTO: 'INTO';
IS: 'IS';
JOIN: 'JOIN';
NOT: 'NOT';
NULL: 'NULL';
NUMERIC: 'NUMERIC';
NVARCHAR: 'NVARCHAR';
ON: 'ON';
OR: 'OR';
SELECT: 'SELECT';
SET: 'SET';
SMALLINT: 'SMALLINT';
TABLE: 'TABLE';
THEN: 'THEN';
TINYINT: 'TINYINT';
UPDATE: 'UPDATE';
USE: 'USE';
VALUES: 'VALUES';
VARCHAR: 'VARCHAR';
WHEN: 'WHEN';
WHERE: 'WHERE';

QUOTE: '\'' { textMode = !textMode; };
QUOTED: {textMode}?=> ~('\'')*;

EQUALS: '=';
NOT_EQUALS: '!=';
SEMICOLON: ';';
COMMA: ',';
OPEN: '(';
CLOSE: ')';
VARIABLE: '@' NAME;
NAME:
    ( LETTER | '#' | '_' ) ( LETTER | NUMBER | '#' | '_' | '.' )*
    ;
NUMBER: DIGIT+;

fragment LETTER: 'a'..'z' | 'A'..'Z';
fragment DIGIT: '0'..'9';
SPACE
    :
    ( ' ' | '\t' | '\n' | '\r' )+
    { skip(); }
    ;

JDK 1.6 说 code too large 并且无法编译它.为什么以及如何解决问题?

JDK 1.6 says code too large and can't compile it. Why and how to solve the problem?

推荐答案

其实我不会说这是一个很大的语法，它不能产生合理大小的代码肯定是有原因的.

Actually I wouldn't say this is a big grammar, and there must be a reason why it doesn't produce reasonably sized code.

我认为问题与这条规则直接相关:

I think the problem is directly related to this rule:

QUOTED: {textMode}?=> ~('\'')*;

有什么特别的理由为什么你想要 QUOTED 部分作为一个单独的标记，而不是将它与引用结合起来，因为 Bart 也把它放在他的语法中?这也会使 textMode 变量过时.

Is there any particular reason why you want the QUOTED part as a separate token, rather than leaving it combined with the quote, as Bart also put it in his grammar? This would also make the textMode variable obsolete.

删除 QUOTE 并用 QUOTE 替换

Dropping the QUOTE and replacing QUOTED with

QUOTED: '\'' (~'\'')* '\'';

即使不拆分语法，也很可能会解决问题.

most probably will solve the problem, even without splitting the grammar.

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