Parsing Antlr4解析编号失败
我试图使用antlr4解析数字(双精度和整数),但未能成功。希望有人能帮助我 我的测试代码是:Parsing Antlr4解析编号失败,parsing,antlr4,Parsing,Antlr4,我试图使用antlr4解析数字(双精度和整数),但未能成功。希望有人能帮助我 我的测试代码是: public class TestAntlr4 { @Test public void test() throws IOException { String input = "30"; CharStream inputCharStream = new ANTLRInputStream(new StringReader(input));
public class TestAntlr4 {
@Test
public void test() throws IOException {
String input = "30";
CharStream inputCharStream = new ANTLRInputStream(new StringReader(input));
// create a lexer that feeds off of input CharStream
TokenSource tokenSource = new GqlLexer(inputCharStream);
// create a buffer of tokens pulled from the lexer
TokenStream inputTokenStream = new CommonTokenStream(tokenSource);
// create a parser that feeds off the tokens buffer
TestAntlr4Parser parser = new TestAntlr4Parser(inputTokenStream);
parser.removeErrorListeners(); // remove ConsoleErrorListener
parser.addErrorListener(new VerboseListener());
parser.getInterpreter().setPredictionMode(PredictionMode.LL_EXACT_AMBIG_DETECTION);
NumberContext context = parser.number();
System.out.println(context.toString());
}
}
我的antlr4语法是:
grammar TestAntlr4 ;
number
: INT_NUMBER
| DOUBLE_NUMBER ;
DOUBLE_NUMBER
: ('+'|'-')? INTEGER '.' INTEGER? ;
INT_NUMBER
: ('+'|'-')? INTEGER ;
WS
: [ \t\r\n]+ -> skip ; // skip spaces, tabs, newlines
fragment INTEGER
: '0'
| '1'..'9' ('0'..'9')* ;
fragment DIGIT
: [0-9] ;
结果是:
rule stack: [number]
line 1:0 at [@0,0:1='30',<31>,1:0]: mismatched input '30' expecting {DOUBLE_NUMBER, INT_NUMBER}
[]
规则堆栈:[编号]
第1:0行位于[@0,0:1='30',1:0]:输入“30”不匹配,应为{DOUBLE\u NUMBER,INT\u NUMBER}
[]
谁能告诉我这有什么问题吗 语法似乎还可以。使用输入“30”对我来说词法和语法分析很好: 编译并运行良好 更新:
我注意到您的lexer和解析器的名称不同,您会有一个简单的复制/粘贴错误吗?通常在生成类时,所有类都是根据语法名称统一命名的。请参阅下面的更新答案。感谢您的快速响应,您真的解决了我的问题。实际上,我在实际项目中遇到了一个antrl4问题,我简化了测试语法,但在复制和修改单元测试代码时出现了一个错误。观察得真好!当我纠正Lexer时,它工作:>TokenSource-TokenSource=newtestantlr4lexer(inputCharStream);
[@0,0:1='30',<INT_NUMBER>,1:0]
[@1,2:1='<EOF>',<EOF>,1:2]
[@0,0:6='30.3343',<DOUBLE_NUMBER>,1:0]
[@1,7:6='<EOF>',<EOF>,1:7]
AntlrInputStream inputStream = new AntlrInputStream(stream);
Grammar1Lexer lexer = new Grammar1Lexer(inputStream);
CommonTokenStream tokenStream = new CommonTokenStream(lexer);
Grammar1Parser parser = new Grammar1Parser(tokenStream);
IParseTree tree = parser.number();
Grammar1Visitor visitor = new Grammar1Visitor();
visitor.Visit(tree);