【问题】
如下的antlr v3的代码：
grammar DDParserDemo;
options {
output = AST;
ASTLabelType = CommonTree; // type of $stat.tree ref etc...
}
ID : ('a'..'z'|'A'..'Z'|'_') ('a'..'z'|'A'..'Z'|'0'..'9'|'_')*
;
FLOAT
: ('0'..'9')+ '.' ('0'..'9')* EXPONENT?
| '.' ('0'..'9')+ EXPONENT?
| ('0'..'9')+ EXPONENT
;
COMMENT
: '//' ~('\n'|'\r')* '\r'? '\n' {$channel=HIDDEN;}
| '/*' ( options {greedy=false;} : . )* '*/' {$channel=HIDDEN;}
;
WS : ( ' '
| '\t'
| '\r'
| '\n'
) {skip();}
;
STRING
: '"' ( ESC_SEQ | ~('\\'|'"') )* '"'
;
CHAR: '\'' ( ESC_SEQ | ~('\''|'\\') ) '\''
;
fragment
EXPONENT : ('e'|'E') ('+'|'-')? ('0'..'9')+ ;
fragment
HEX_DIGIT : ('0'..'9'|'a'..'f'|'A'..'F') ;
fragment
ESC_SEQ
: '\\' ('b'|'t'|'n'|'f'|'r'|'\"'|'\''|'\\')
| UNICODE_ESC
| OCTAL_ESC
;
fragment
OCTAL_ESC
: '\\' ('0'..'3') ('0'..'7') ('0'..'7')
| '\\' ('0'..'7') ('0'..'7')
| '\\' ('0'..'7')
;
fragment
UNICODE_ESC
: '\\' 'u' HEX_DIGIT HEX_DIGIT HEX_DIGIT HEX_DIGIT
;
fragment
DIGIT
: '0'..'9';
DECIMAL_VALUE
: '1'...'9' DIGIT*;
HEX_VALUE
: '0x' HEX_DIGIT+;
startParse : (identification)+;
identification : definiton WS* ','? WS*
;
definiton : (ID)^ ('\t'!|' '!)+ (DECIMAL_VALUE | HEX_VALUE)
;用generate->generate code，结果出错：
log为：
[09:25:30] error(100): DDParserDemo.g:67:7: syntax error: antlr: NoViableAltException(37@[]) [09:25:30] error(100): DDParserDemo.g:0:1: syntax error: assign.types: org.antlr.runtime.EarlyExitException [09:25:30] error(100): DDParserDemo.g:0:1: syntax error: assign.types: MismatchedTreeNodeException(3!=34) [09:25:30] error(100): DDParserDemo.g:0:1: syntax error: assign.types: MismatchedTreeNodeException(32!=3) [09:25:30] java.lang.ArrayIndexOutOfBoundsException: 2 at org.antlr.tool.Rule.trackRuleReferenceInAlt(Rule.java:294) at org.antlr.tool.Grammar.altReferencesRule(Grammar.java:2011) at org.antlr.grammar.v3.DefineGrammarItemsWalker.atom(DefineGrammarItemsWalker.java:3787) at org.antlr.grammar.v3.DefineGrammarItemsWalker.element(DefineGrammarItemsWalker.java:2416) at org.antlr.grammar.v3.DefineGrammarItemsWalker.alternative(DefineGrammarItemsWalker.java:2052) at org.antlr.grammar.v3.DefineGrammarItemsWalker.block(DefineGrammarItemsWalker.java:1924) at org.antlr.grammar.v3.DefineGrammarItemsWalker.rule(DefineGrammarItemsWalker.java:1515) at org.antlr.grammar.v3.DefineGrammarItemsWalker.rules(DefineGrammarItemsWalker.java:1115) at org.antlr.grammar.v3.DefineGrammarItemsWalker.grammarSpec(DefineGrammarItemsWalker.java:578) at org.antlr.grammar.v3.DefineGrammarItemsWalker.grammar_(DefineGrammarItemsWalker.java:256) at org.antlr.tool.Grammar.defineGrammarSymbols(Grammar.java:791) at org.antlr.tool.CompositeGrammar.defineGrammarSymbols(CompositeGrammar.java:370) at org.antlr.tool.Grammar.setGrammarContent(Grammar.java:650) at org.antlr.works.grammar.antlr.ANTLRGrammarEngineImpl.createLexerGrammarFromCombinedGrammar(ANTLRGrammarEngineImpl.java:218) at org.antlr.works.grammar.antlr.ANTLRGrammarEngineImpl.createCombinedGrammar(ANTLRGrammarEngineImpl.java:204) at org.antlr.works.grammar.antlr.ANTLRGrammarEngineImpl.createGrammars(ANTLRGrammarEngineImpl.java:165) at org.antlr.works.grammar.antlr.ANTLRGrammarEngineImpl.analyze(ANTLRGrammarEngineImpl.java:272) at org.antlr.works.grammar.engine.GrammarEngineImpl.analyze(GrammarEngineImpl.java:325) at org.antlr.works.grammar.CheckGrammar.run(CheckGrammar.java:70) at java.lang.Thread.run(Unknown Source) [09:25:30] error(100): D:\DevRoot\IndustrialMobileAutomation\HandheldDataSetter\ANTLR\projects\v1.5\DDParserDemo\DDParserDemo.g:67:7: syntax error: antlr: NoViableAltException(37@[]) [09:25:30] error(100): D:\DevRoot\IndustrialMobileAutomation\HandheldDataSetter\ANTLR\projects\v1.5\DDParserDemo\DDParserDemo.g:0:1: syntax error: assign.types: org.antlr.runtime.EarlyExitException [09:25:30] error(100): D:\DevRoot\IndustrialMobileAutomation\HandheldDataSetter\ANTLR\projects\v1.5\DDParserDemo\DDParserDemo.g:0:1: syntax error: assign.types: MismatchedTreeNodeException(3!=34) [09:25:30] error(100): D:\DevRoot\IndustrialMobileAutomation\HandheldDataSetter\ANTLR\projects\v1.5\DDParserDemo\DDParserDemo.g:0:1: syntax error: assign.types: MismatchedTreeNodeException(32!=3) [09:25:30] error(10): internal error: D:\DevRoot\IndustrialMobileAutomation\HandheldDataSetter\ANTLR\projects\v1.5\DDParserDemo\DDParserDemo.g : java.lang.NullPointerException org.antlr.tool.Grammar.generateMethodForRule(Grammar.java:1759) org.antlr.grammar.v3.CodeGenTreeWalker.rules(CodeGenTreeWalker.java:1418) org.antlr.grammar.v3.CodeGenTreeWalker.grammarSpec(CodeGenTreeWalker.java:1392) org.antlr.grammar.v3.CodeGenTreeWalker.grammar_(CodeGenTreeWalker.java:503) org.antlr.codegen.CodeGenerator.genRecognizer(CodeGenerator.java:415) org.antlr.Tool.generateRecognizer(Tool.java:661) org.antlr.Tool.process(Tool.java:474) org.antlr.works.generate.CodeGenerate.generate(CodeGenerate.java:104) org.antlr.works.generate.CodeGenerate.run(CodeGenerate.java:185) java.lang.Thread.run(Unknown Source) |
【解决过程】
1.后来去看了对应的66,67行，是：
DECIMAL_VALUE : '1'...'9' DIGIT*;
然后和之前的代码对比后才发现，原来是，表示范围的的话，是两个点，而不是三个点：
fragment DIGIT : '0'..'9';
所以，去改为2个点：
DECIMAL_VALUE : '1'..'9' DIGIT*;
即可消除出错了。
【总结】
antlr中的语法，虽然很多定义都和正则很类似，但是对于这个表示范围的语法，觉得还是比较诡异的。
竟然是两个点，不是三个点，需要以后写代码的时候，注意一下。
转载请注明：在路上 » 【已解决】Antlr v3代码编译出错：syntax error: antlr: NoViableAltException(37@[])