Interpreter.java 文件源码

/**
 * Parses a source file using ANTLR4, and walks over the parse tree to
 * interpret this source file as a Java object.
 * 
 * @param c
 *            input character stream
 * @param path
 *            location of the file
 * @return an interpreted source file, or null in case of an error.
 */
@Nullable
private ReoFile<T> parse(CharStream c, String path) {
    ReoLexer lexer = new ReoLexer(c);
    CommonTokenStream tokens = new CommonTokenStream(lexer);
    ReoParser parser = new ReoParser(tokens);

    ErrorListener errListener = new ErrorListener(m);
    parser.removeErrorListeners();
    parser.addErrorListener(errListener);
    ParseTree tree = parser.file();
    if (errListener.hasError)
        return null;
    ParseTreeWalker walker = new ParseTreeWalker();
    listener.setFileName(path);
    walker.walk(listener, tree);
    return listener.getMain();
}