AnnisQueryProcessor.java 文件源码

private ParserRuleContext parseAnnisQuery (String query) {
    Lexer lexer = new AqlLexer((CharStream) null);
    ParserRuleContext tree = null;
    Antlr4DescriptiveErrorListener errorListener = new Antlr4DescriptiveErrorListener(
            query);
    // Like p. 111
    try {
        // Tokenize input data
        ANTLRInputStream input = new ANTLRInputStream(query);
        lexer.setInputStream(input);
        CommonTokenStream tokens = new CommonTokenStream(lexer);
        parser = new AqlParser(tokens);
        // Don't throw out erroneous stuff
        parser.setErrorHandler(new BailErrorStrategy());
        lexer.removeErrorListeners();
        lexer.addErrorListener(errorListener);
        parser.removeErrorListeners();
        parser.addErrorListener(errorListener);
        // Get starting rule from parser
        Method startRule = AqlParser.class.getMethod("start");
        tree = (ParserRuleContext) startRule.invoke(parser,
                (Object[]) null);
    }
    // Some things went wrong ...
    catch (Exception e) {
        log.error("Could not parse query. "
                + "Please make sure it is well-formed.");
        log.error(errorListener.generateFullErrorMsg().toString());
        addError(errorListener.generateFullErrorMsg());
    }
    return tree;
}