ANTLR中文手册之三（ANTLR 元语言－元语言词汇表…

/** This method is called by YourLexer.nextToken()

 *  when the lexer has

 * hit EOF condition. EOF is NOT a character.

 * This method is not called if EOF is reached

 * during syntactic predicate evaluation or during

 * evaluation of normal lexical rules, which

 * presumably would be an IOException. This

 * traps the "normal" EOF * condition.

 *

 * uponEOF() is called after the complete evaluation

 * of the previous token and only if your parser asks

 * for another token beyond that last non-EOF token.

 *

 * You might want to throw token or char stream

 * exceptions like: "Heh, premature eof" or a retry

 * stream exception ("I found the end of this file,

 * go back to referencing file").

 */

public void uponEOF()

  throws TokenStreamException, CharStreamException

{

}

文件结束条件是一个位比特（从2.7.1版本开始）。因为Terence 将-1当作一个字符而不是一个整型数。(-1 是 '\uFFFF'...晕！).

字符串

字符串常数一个由双引号括起来的一系列字符。在字符串中的字符可以是作为字符也同样合法的转义字符(八进制，Unicode等)。当前，ANTLR实际上不允许Unicode出现在字符串常量中（你不得不用转义符）。这是因为在anglr.g文件中设定charVocabulary选项为ascii.

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