GraphParser.java 文件源码

public GraphParser(InputStream is) throws GraphParserException {
    DOTLexer lexer = null;
    DOTParser parser = null;
    try {
        lexer = new DOTLexer(new ANTLRInputStream(is));
        lexer.addErrorListener(new ErrorListener());

        parser = new DOTParser(new CommonTokenStream(lexer));
        parser.setErrorHandler(new ExceptionErrorStrategy());
        parser.addErrorListener(new ErrorListener());

        ParseTree tree = parser.graph();
        ParseTreeWalker.DEFAULT.walk(new NodeListener(), tree);
        ParseTreeWalker.DEFAULT.walk(new EdgeListener(), tree);
    }
    catch (Throwable t) {
        if (mErrMsg != null) throw new GraphParserException(mErrMsg, t);
        if (lexer != null) {
            mErrMsg = "at line " + lexer.getLine() + ":" + lexer.getCharPositionInLine();
            throw new GraphParserException(mErrMsg, t);
        }
        throw new GraphParserException(t);
    }

    if (mErrMsg != null) throw new GraphParserException(mErrMsg);
}