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我想創建我的第一個ANTLR3樹語法,但我一直打同樣的問題。分析器的輸出是:ANTLR3樹語法:循環沒有匹配任何東西在輸入'EOF'
$ echo 'foo, bar' | ./run.sh
foo bar
TreeGrammar.g: node from line 0:0 required (...)+ loop did not match anything at input 'EOF'
Exception in thread "main" java.lang.NullPointerException
at Driver.main(Driver.java:29)
輸出清楚地表明,階段-1解析器結果在右標記(「富」和「酒吧」)。不知何故,stage-2樹解析器拒絕解析stage-1的結果。由於代碼是非常基本的,那一定是我的一部分;-)
這裏是我的簡單測試代碼一些簡單的,愚蠢的監督:
Grammar.g:
grammar Grammar;
options {
output = AST;
}
statement: word (','! word)* EOF!;
word: ID;
ID: ('a'..'z'|'A'..'Z')+;
WS: (' ' | '\t' | '\n' | '\r')+ { $channel = HIDDEN; } ;
TreeGrammar.g:
tree grammar TreeGrammar;
options {
tokenVocab = Grammar;
ASTLabelType = CommonTree;
output = template;
}
statement: word+;
word: ID;
Driver.java:
import java.io.*;
import org.antlr.runtime.*;
import org.antlr.runtime.tree.*;
import org.antlr.stringtemplate.*;
public class Driver {
public static void main(String[] args) throws Exception {
FileReader groupFileR = new FileReader("Template.stg");
StringTemplateGroup templates = new StringTemplateGroup(groupFileR);
groupFileR.close();
ANTLRInputStream input = new ANTLRInputStream(System.in);
GrammarLexer lexer = new GrammarLexer(input);
CommonTokenStream tokens = new CommonTokenStream(lexer);
GrammarParser parser = new GrammarParser(tokens);
GrammarParser.statement_return result = parser.statement();
CommonTree t = (CommonTree)result.getTree();
System.out.println(t.toStringTree());
CommonTreeNodeStream nodes = new CommonTreeNodeStream(t);
nodes.setTokenStream(tokens);
TreeGrammar walker = new TreeGrammar(nodes);
walker.setTemplateLib(templates);
walker.statement();
TreeGrammar.statement_return r2 = walker.statement();
StringTemplate output = (StringTemplate) r2.getTemplate();
System.out.println(output.toString());
}
}