Walker.java 文件源码

private SourceContext buildAntlrTree(String source) {
    ANTLRInputStream stream = new ANTLRInputStream(source);
    PainlessLexer lexer = new EnhancedPainlessLexer(stream, sourceName);
    PainlessParser parser = new PainlessParser(new CommonTokenStream(lexer));
    ParserErrorStrategy strategy = new ParserErrorStrategy(sourceName);

    lexer.removeErrorListeners();
    parser.removeErrorListeners();

    if (settings.isPicky()) {
        setupPicky(parser);
    }

    parser.setErrorHandler(strategy);

    return parser.source();
}