GoParserFactory.java 文件源码

protected void configureParser(@NonNull Parser parser, @NonNull ParserConfiguration configuration) {
    ParserATNSimulator interpreter = parser.getInterpreter();

    // common configuration
    interpreter.force_global_context = false;
    interpreter.always_try_local_context = true;
    interpreter.optimize_tail_calls = true;
    parser.setBuildParseTree(true);
    parser.removeErrorListeners();

    switch (configuration) {
    case FASTEST:
        interpreter.setPredictionMode(PredictionMode.SLL);
        interpreter.tail_call_preserves_sll = false;
        interpreter.treat_sllk1_conflict_as_ambiguity = true;
        parser.setErrorHandler(new BailErrorStrategy());
        break;

    case SLL:
        throw new UnsupportedOperationException("The tail_call_preserves_sll flag cannot change within a single ATN instance.");
        //interpreter.setPredictionMode(PredictionMode.SLL);
        //interpreter.tail_call_preserves_sll = true;
        //interpreter.treat_sllk1_conflict_as_ambiguity = true;
        //parser.setErrorHandler(new BailErrorStrategy<Token>());
        //break;

    case HYBRID:
        interpreter.setPredictionMode(PredictionMode.LL);
        interpreter.tail_call_preserves_sll = false;
        interpreter.treat_sllk1_conflict_as_ambiguity = true;
        parser.setErrorHandler(new BailErrorStrategy());
        break;

    case HYBRID_SLL:
        throw new UnsupportedOperationException("The tail_call_preserves_sll flag cannot change within a single ATN instance.");
        //interpreter.setPredictionMode(PredictionMode.LL);
        //interpreter.tail_call_preserves_sll = true;
        //interpreter.treat_sllk1_conflict_as_ambiguity = true;
        //parser.setErrorHandler(new BailErrorStrategy<Token>());
        //break;

    case PRECISE:
        interpreter.setPredictionMode(PredictionMode.LL);
        interpreter.tail_call_preserves_sll = false;
        interpreter.treat_sllk1_conflict_as_ambiguity = false;
        parser.setErrorHandler(new DefaultErrorStrategy());
        parser.addErrorListener(DescriptiveErrorListener.INSTANCE);
        break;

    default:
        throw new IllegalArgumentException("Invalid configuration.");
    }
}