OTLDListener.java 文件源码

/**
 * Parses the supplied input using the OTLDListener and returns it after walking it
 * @param reader input to parse
 * @return walked OTLDListener
 * @throws IOException
 */
public static OTLDListener parseFile(InputStream reader) throws IOException {
    OTLDErrorListener errorListener = new OTLDErrorListener();
    ANTLRInputStream stream = new ANTLRInputStream(reader);

    Lexer lexer = new otldLexer(stream);
    lexer.removeErrorListeners();
    lexer.addErrorListener(errorListener);
    TokenStream tokens = new CommonTokenStream(lexer);

    otldParser parser = new otldParser(tokens);
    parser.removeErrorListeners();
    parser.addErrorListener(errorListener);
    ParseTree tree = parser.program();

    OTLDListener railroad = new OTLDListener();

    if (errorListener.getErrors().isEmpty()) {
        ParseTreeWalker walker = new ParseTreeWalker();
        walker.walk(railroad, tree);
    } else {
        railroad.errors.addAll(errorListener.getErrors());
    }

    return railroad;
}