Java 类org.antlr.v4.runtime.CharStream 实例源码

@Override
public SortedMap<Integer, String> parseString(String fieldString) {
    CharStream is = CharStreams.fromString(fieldString);
    DrawGrammarLexer lex = new DrawGrammarLexer(is);
    CommonTokenStream tokens = new CommonTokenStream(lex);
    DrawGrammarParser parser = new DrawGrammarParser(tokens);
    palette = Palette.makeDefaultPalette("DarkSpectrum");
    final SortedMap<Integer, String> resultMap;
    try {
        resultMap = parser.root().map;
    } catch (RecognitionException | NullPointerException | StringIndexOutOfBoundsException | RasterFormatException re) {
        //Something wrong with the parsing do not update.
        return null;
    }
    return resultMap;
}

/**
 * @param args the command line arguments
 * @throws java.io.IOException
 * @throws java.net.URISyntaxException
 */
public static void main(String[] args) throws IOException, URISyntaxException {
    final String entryPoint;
    final URL res;
    switch (args.length) {
    case 2:
        res = Paths.get(args[0]).toUri().toURL();
        entryPoint = args[1];
        break;
    default:
        System.err.println("Supply two parameters in the following order:\n- file name of the main function\n- name of the main function\n\nFor example: hello.ct main:argc:argv");
        return;
    }
    final CharStream inp = CharStreams.fromStream(res.openStream());
    final GrammarLexer lex = new GrammarLexer(inp);
    final TokenStream toks = new CommonTokenStream(lex);
    final GrammarParser parser = new GrammarParser(toks);
    System.out.println(new Translator(res.toURI()).generate(parser.program(), entryPoint));
}

/**
 * @throws InvalidQueryException if the given query contains invalid characters or is incomplete
 */
public SqlGrammarParser.SelectStatementContext parse(String query) {
    log.trace("About to parse [{}]", query);
    long now = currentTimeMillis();

    CharStream input = CharStreams.fromString(query);
    SqlGrammarLexer lexer = new SqlGrammarLexer(input);
    TokenStream tokenStream = new CommonTokenStream(lexer);
    SqlGrammarParser parser = new SqlGrammarParser(tokenStream);

    parser.removeErrorListeners();
    parser.addErrorListener(new RaiseExceptionErrorListener());

    SqlGrammarParser.SelectStatementContext result = parser.selectStatement();

    log.trace("Successfully parsed [{}] into [{}] in [{}ms]",
            query, result.toStringTree(parser), currentTimeMillis() - now);

    return result;
}

@Override
public Token nextToken() {
    if (stashedNext != null) {
        previous = stashedNext;
        stashedNext = null;
        return previous;
    }
    Token next = super.nextToken();
    if (insertSemicolon(previous, next)) {
        stashedNext = next;
        previous = _factory.create(new Pair<TokenSource, CharStream>(this, _input), PainlessLexer.SEMICOLON, ";",
                Lexer.DEFAULT_TOKEN_CHANNEL, next.getStartIndex(), next.getStopIndex(), next.getLine(), next.getCharPositionInLine());
        return previous;
    } else {
        previous = next;
        return next;
    }
}

@Override
public void recover(final LexerNoViableAltException lnvae) {
    final CharStream charStream = lnvae.getInputStream();
    final int startIndex = lnvae.getStartIndex();
    final String text = charStream.getText(Interval.of(startIndex, charStream.index()));

    Location location = new Location(sourceName, _tokenStartCharIndex);
    String message = "unexpected character [" + getErrorDisplay(text) + "].";
    char firstChar = text.charAt(0);
    if ((firstChar == '\'' || firstChar == '"') && text.length() - 2 > 0 && text.charAt(text.length() - 2) == '\\') {
        /* Use a simple heuristic to guess if the unrecognized characters were trying to be a string but has a broken escape sequence.
         * If it was add an extra message about valid string escape sequences. */
        message += " The only valid escape sequences in strings starting with [" + firstChar + "] are [\\\\] and [\\"
                + firstChar + "].";
    }
    throw location.createError(new IllegalArgumentException(message, lnvae));
}

private void parseInputStream(CharStream inputStream, OboParseResultListener listener) {
  final OboLexer l = new OboLexer(inputStream);
  final Antlr4OboParser p = new Antlr4OboParser(new CommonTokenStream(l));

  p.addErrorListener(new BaseErrorListener() {
    @Override
    public void syntaxError(Recognizer<?, ?> recognizer, Object offendingSymbol, int line,
        int charPositionInLine, String msg, RecognitionException e) {
      throw new IllegalStateException("Failed to parse at line " + line + " due to " + msg, e);
    }
  });

  if (debug) {
    p.addErrorListener(new DiagnosticErrorListener());
  }

  p.addParseListener(new OboParserListener(listener));

  p.oboFile();
}

public EObject parse(final String typeExpression, final Scope scope) {
    final CharStream charStream = CharStreams.fromString(typeExpression);
    final TypeExpressionLexer lexer = new TypeExpressionLexer(charStream);
    final TokenStream tokenStream = new CommonTokenStream(lexer);
    final TypeExpressionParser typeExpressionParser = new TypeExpressionParser(tokenStream);

    lexer.removeErrorListeners();
    typeExpressionParser.removeErrorListeners();

    final ParserErrorCollector errorCollector = new ParserErrorCollector();
    lexer.addErrorListener(errorCollector);
    typeExpressionParser.addErrorListener(errorCollector);

    final TypeExpressionParser.Type_exprContext typeExpr = typeExpressionParser.type_expr();

    final EObject anyType = new TypeExpressionBuilder(scope, ARRAY_TYPE).visit(typeExpr);
    scope.getResource().getErrors().addAll(errorCollector.getErrors());

    return anyType;
}

private void parseInputStream(CharStream inputStream, OboParseResultListener listener) {
  final OboLexer l = new OboLexer(inputStream);
  final Antlr4OboParser p = new Antlr4OboParser(new CommonTokenStream(l));

  p.addErrorListener(new BaseErrorListener() {
    @Override
    public void syntaxError(Recognizer<?, ?> recognizer, Object offendingSymbol, int line,
        int charPositionInLine, String msg, RecognitionException e) {
      throw new IllegalStateException("Failed to parse at line " + line + " due to " + msg, e);
    }
  });

  if (debug) {
    p.addErrorListener(new DiagnosticErrorListener());
  }

  p.addParseListener(new OboParserListener(listener));

  p.oboFile();
}

public static <L extends Lexer, P extends Parser> P newParser(
    Function<CharStream, L> lexerFactory,
    Function<TokenStream, P> parserFactory,
    String input,
    boolean useBailErrorStrategy,
    boolean removeErrorListeners) {
  CharStream charStream = new ANTLRInputStream(input);
  L lexer = lexerFactory.apply(charStream);
  if (removeErrorListeners) {
    lexer.removeErrorListeners();
  }

  TokenStream tokenStream = new CommonTokenStream(lexer);
  P parser = parserFactory.apply(tokenStream);
  if (useBailErrorStrategy) {
    parser.setErrorHandler(new BailErrorStrategy());
  }
  if (removeErrorListeners) {
    parser.removeErrorListeners();
  }

  return parser;
}

/**
 * Parse an interval, for example <tt>[1,-]</tt> or <tt>-</tt> (a wildcard) or <tt>[1,4]</tt>.
 * Only fixed values are allowed, no variables.
 *
 * @param intervalAsString the string to be parsed.
 * @return a LowerBoundedInterval as the runtime representation of interval strings.
 * @throws ParseException in case the string doesn't fit the given fixed-interval grammar.
 */
public static LowerBoundedInterval parse(String intervalAsString) throws ParseException {
  CharStream charStream = new ANTLRInputStream(intervalAsString);
  CellExpressionLexer lexer = new CellExpressionLexer(charStream);
  TokenStream tokens = new CommonTokenStream(lexer);
  CellExpressionParser parser = new CellExpressionParser(tokens);
  parser.removeErrorListeners();
  parser.addErrorListener(new ThrowingErrorListener());
  try {
    CellExpressionParser.Fixed_intervalContext ctx = parser.fixed_interval();
    if (ctx == null) {
      throw new ParseException(0, 0, "Expected fixed interval");
    }
    return INSTANCE.visit(ctx);
  } catch (ParseRuntimeException runtimeException) {
    throw runtimeException.getParseException();
  }
}

public static FilterPredicate compile(String predicateString){
    predicateString = predicateString.trim();
    if(predicateString.isEmpty()){
        return FilterPredicate.empty();
    }
    PredicateCompileErrorListener errorListener = new PredicateCompileErrorListener(predicateString);

    CharStream stream = CharStreams.fromString(predicateString);
    PredicateLexer lexer = new PredicateLexer(stream);
    lexer.removeErrorListener(ConsoleErrorListener.INSTANCE);
    lexer.addErrorListener(errorListener);
    CommonTokenStream tokens = new CommonTokenStream(lexer);
    PredicateParser parser = new PredicateParser(tokens);
    parser.removeErrorListener(ConsoleErrorListener.INSTANCE);
    parser.addErrorListener(errorListener);
    FilterPredicateVisitor filterPredicateVisitor = new FilterPredicateVisitor();
    return  filterPredicateVisitor.visit(parser.compilationUnit());
}

@Test
public void test() {

    final CharStream charStream = CharStreams.fromString("\r\nSELECT\r\n 1");

    final TSqlLexer lexer = new TSqlLexer(charStream);

    final CommonTokenStream stream = new CommonTokenStream(lexer);

    stream.fill();
    TSqlParser parser = new TSqlParser(stream);
    ParseTree child = parser.tsql_file().getChild(0);
    DefaultLinesProvider lines = new DefaultLinesProvider(stream);
    int line = lines.getLine(new ParsedNode(child));
    Assert.assertEquals(2, line);

}

/**
 * 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();
}

static MysqlParser.ScriptContext parse(CharStream cs) {
    MysqlLexer lexer = new MysqlLexer(cs);
    CommonTokenStream tokens = new CommonTokenStream(lexer);
    tokens.setTokenSource(lexer);
    MysqlParser parser = new MysqlParser(tokens);
    parser.setErrorHandler(new BailErrorStrategy());
    boolean success = false;
    try {
        MysqlParser.ScriptContext script = parser.script();
        success = true;
        return script;
    }
    finally {
        if (!success && (parser.lastStatement != null)) {
            _log.debug("last passed statement: {}", ((ParseTree)parser.lastStatement).getText());
        }
    }
}

private static byte[] getBytes(Literal_value_binaryContext rule) {
    Token token = rule.STRING_LITERAL().getSymbol();
    byte[] bytes = new byte[token.getStopIndex() - token.getStartIndex() - 1];
    CharStream cs = token.getInputStream();
    int pos = cs.index();
    cs.seek(token.getStartIndex() + 1);
    int j = 0;
    for (int i = 0; i < bytes.length; i++) {
        int ch = cs.LA(i + 1);
        if (ch == '\\') {
            i++;
            ch = cs.LA(i + 1);
            if (ch == '0') {
                ch = 0;
            }
            else if (ch == 'n') {
                ch = '\n';
            }
            else if (ch == 'r') {
                ch = '\r';
            }
            else if (ch == 'Z') {
                ch = '\032';
            }
        }
        bytes[j] = (byte) ch;
        j++;
    }
    cs.seek(pos);
    if (j != bytes.length) {
        // esacpe characters
        byte[] old = bytes;
        bytes = new byte[j];
        System.arraycopy(old, 0, bytes, 0, j);
    }
    return bytes;
}

private void compileFiles(List<RawFile> files, OOPSourceCodeModel srcModel, List<String> projectFileTypes) {
    for (RawFile file : files) {
        try {
            CharStream charStream = new ANTLRInputStream(file.content());
            GolangLexer lexer = new GolangLexer(charStream);
            TokenStream tokens = new CommonTokenStream(lexer);
            GolangParser parser = new GolangParser(tokens);
            SourceFileContext sourceFileContext = parser.sourceFile();
            parser.setErrorHandler(new BailErrorStrategy());
            parser.getInterpreter().setPredictionMode(PredictionMode.SLL);
            ParseTreeWalker walker = new ParseTreeWalker();
            GolangBaseListener listener = new GoLangTreeListener(srcModel, projectFileTypes, file);
            walker.walk(listener, sourceFileContext);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

private SyntaxErrorListener getSyntaxTreeErrors(String iFlowResource) {
    InputStream inputStream = null;

    try {
        File file = new File(getClass().getResource(iFlowResource).getFile());
        inputStream = new FileInputStream(file);

        CharStream cs = new ANTLRInputStream(inputStream);
        TokenStream tokenStream = new CommonTokenStream(new WUMLLexer(cs));
        WUMLParser parser = new WUMLParser(tokenStream);
        SyntaxErrorListener errorListener = new SyntaxErrorListener();
        parser.addErrorListener(errorListener);
        ParseTree tree = parser.sourceFile();
        return errorListener;

    } catch (Exception e) {
        return null;
    }
}

private static Program combineInput(boolean literate, String... fileNames) throws IOException {
    final Program result = new Program();

    for (String fileName : fileNames) {
        CharStream stream;
        if (!literate) {
            stream = CharStreams.fromFileName(fileName);
        } else {
            stream = CharStreams.fromChannel(
                streamToChannel(literate(lines(Paths.get(fileName)))),
                4096,
                CodingErrorAction.REPLACE,
                fileName
            );
        }
        result.accumulate(PARSER.parse(stream));
    }

    return result;
}

public static <L extends Lexer, P extends Parser> P newParser(
    Function<CharStream, L> lexerFactory,
    Function<TokenStream, P> parserFactory,
    String input,
    boolean useBailErrorStrategy,
    boolean removeErrorListeners) {
  CharStream charStream = new ANTLRInputStream(input);
  L lexer = lexerFactory.apply(charStream);
  if (removeErrorListeners) {
    lexer.removeErrorListeners();
  }

  TokenStream tokenStream = new CommonTokenStream(lexer);
  P parser = parserFactory.apply(tokenStream);
  if (useBailErrorStrategy) {
    parser.setErrorHandler(new BailErrorStrategy());
  }
  if (removeErrorListeners) {
    parser.removeErrorListeners();
  }

  return parser;
}

public static FillerRequest createRequest(final SourceLinesProvider linesProvider, final InputFile file, final Charset encoding)
        throws IOException, FileNotFoundException {
    final CharStream mainStream = CharStreams.fromPath(file.path(), encoding);
    final CharStream charStream = new CaseChangingCharStream(mainStream, true);
    final TSqlLexer lexer = new TSqlLexer(charStream);

    lexer.removeErrorListeners();

    final CommonTokenStream stream = new CommonTokenStream(lexer);

    stream.fill();
    final TSqlParser parser = new TSqlParser(stream);
    parser.removeErrorListeners();
    final ParseTree root = parser.tsql_file();
    final FillerRequest antrlFile = new FillerRequest(file, stream, root,
            linesProvider.getLines(new FileInputStream(file.file()), encoding));
    return antrlFile;
}

private static TravnyParser.SchemaFileContext parseContext(String dsl) {
    CharStream cs = new ANTLRInputStream(dsl);
    TravnyLexer lexer = new TravnyLexer(cs);
    lexer.removeErrorListeners();
    lexer.addErrorListener(new BreakingErrorListener());
    CommonTokenStream tokens = new CommonTokenStream(lexer);
    TravnyParser parser = new TravnyParser(tokens);
    parser.removeErrorListeners();
    parser.addErrorListener(new BreakingErrorListener());

    TravnyParser.SchemaFileContext parsed = parser.schemaFile();


    return parsed;
}

static long getResult(String equationString) throws LogicGrammarParsingException {
    CharStream is = CharStreams.fromString(equationString);
    LogicGrammarLexer lex = new LogicGrammarLexer(is);
    CommonTokenStream tokens = new CommonTokenStream(lex);
    LogicGrammarParser parser = new LogicGrammarParser(tokens);
    System.out.println("Parsing equation: " + equationString);
    long final_result;
    try {
        final_result = parser.root().result;
    } catch (RecognitionException | NumberFormatException nfe) {
        throw new LogicGrammarParsingException();
    }
    return final_result;
}

public String processCharStream(CharStream st) throws RecognitionException {
    final GrammarLexer lex = new GrammarLexer(st);
    final TokenStream toks = new CommonTokenStream(lex);
    final GrammarParser parser = new GrammarParser(toks);
    final String body = this.visitProgram(parser.program());
    return body;
}

private int read() {
    int result = input.read();
    if (result == LexerInput.EOF) {
        result = CharStream.EOF;
    }

    return result;
}

private Constructor<? extends Lexer> getLexerCtor() {
    if (lexerCtor == null) {
        try {
            lexerCtor = lexerClass.getConstructor(CharStream.class);
        } catch (NoSuchMethodException | SecurityException e) {
            throw new RuntimeException(e);
        }

    }
    return lexerCtor;
}

private static Expressie doParse(final String expressieString, final Context context) {
    // TEAMBRP-2535 de expressie syntax kan niet goed omgaan met een string waarachter ongedefinieerde velden staan.
    // Door haakjes toe te voegen zal dan een fout gesignaleerd worden, aangezien de content dan niet meer precies
    // gematched kan worden.
    final String expressieStringMetHaakjes = String.format("(%s)", expressieString);

    // Parsing gebeurt met een door ANTLR gegenereerde visitor. Om die te kunnen gebruiken, moet een treintje
    // opgetuigd worden (String->CharStream->Lexer->TokenStream).
    final CharStream cs = CharStreams.fromString(expressieStringMetHaakjes);
    final ParserErrorListener parserErrorListener = new ParserErrorListener();
    final BRPExpressietaalLexer lexer = new BRPExpressietaalLexer(cs);
    // verwijdert de interne listener van de lexer die naar system/out/err wegschrijft
    // expressies als ***bla*** logt bijvoorbeeld unrecognized token errors naar system/out
    // in plaats hiervan neem een eigen error listener op.
    lexer.removeErrorListeners();
    lexer.addErrorListener(parserErrorListener);
    final CommonTokenStream tokens = new CommonTokenStream(lexer);

    final BRPExpressietaalParser parser = new BRPExpressietaalParser(tokens);
    parser.getInterpreter().setPredictionMode(PredictionMode.LL_EXACT_AMBIG_DETECTION);

    // Verwijder bestaande (default) error listeners en voeg de eigen error listener toe.
    parser.removeErrorListeners();
    parser.addErrorListener(parserErrorListener);

    // Maak de parse tree. Hier gebeurt het feitelijke parsing.
    final BRPExpressietaalParser.Brp_expressieContext tree = parser.brp_expressie();

    // Maak een visitor voor parsing.
    final ExpressieVisitor visitor = new ExpressieVisitor(context);
    // De visitor zet een parse tree om in een Expressie. Tenzij er een fout optreedt.
    return visitor.visit(tree);
}

public static SQLTemplate parse(String sql) {
    if (StringUtils.isBlank(sql)) {
        throw new ElasticSearchSQLException("blank sql is not allowed");
    }

    CharStream input = CharStreams.fromString(sql);
    ThrowingExceptionErrorStrategy errorHandler = new ThrowingExceptionErrorStrategy();

    ElasticSearchLexer lexer = new ElasticSearchLexer(input);
    lexer.removeErrorListeners();
    // Lexer error handler
    lexer.addErrorListener(new LexerErrorListener());

    CommonTokenStream token = new CommonTokenStream(lexer);

    ElasticSearchParser parser = new ElasticSearchParser(token);
    // Parser error handler
    parser.setErrorHandler(errorHandler);
    parser.removeErrorListeners();
    parser.addErrorListener(new SyntaxErrorListener());

    ElasticSearchParser.ProgContext progTree = parser.prog();
    ElasticSearchVisitor visitor = new ElasticSearchVisitor();

    ParserResult parsedResult = visitor.visit(progTree);
    if (parsedResult.isSuccess()) {
        return parsedResult.getTemplate();
    }
    throw new ElasticSearchSQLException("SQL parser error !!! " + parsedResult.getFailureReason());
}

public static String getSourceText(ParserRuleContext ctx){
    if (ctx.start == null || ctx.stop == null) {
        return ctx.getText();
    }
    int startIndex = ctx.start.getStartIndex();
    int stopIndex = ctx.stop.getStopIndex();
    if (stopIndex < startIndex) {
        return ""; // Just return the empty string.
    }
    CharStream inputStream = ctx.start.getInputStream();
    return inputStream.getText(new Interval(startIndex, stopIndex));
}

@Override
public void parse(
        Snapshot snapshot,
        Task task,
        SourceModificationEvent event) throws ParseException {

    Assert.notNull(snapshot);

    this.snapshot = snapshot;

    CharStream input =
            new ANTLRInputStream(snapshot.getText().toString());

    Lexer lexer = new ProtobufLexer(input);
    CommonTokenStream tokens = new CommonTokenStream(lexer);
    ProtobufParser parser = new ProtobufParser(tokens);

    parser.removeErrorListeners();
    ParsingErrorListener listener = new ParsingErrorListener();
    parser.addErrorListener(listener);

    ParseTree tree = parser.proto();
    // TODO def and ref phases

    this.errors.clear();
    this.errors.addAll(listener.errors());
}

/**
 * Parses while matching an AQL expression.
 * 
 * @param queryEnvironment
 *            the {@link IReadOnlyQueryEnvironment}
 * @param type
 *            the type to parse
 * @return the corresponding {@link AstResult}
 */
private AstResult parseWhileAqlTypeLiteral(IReadOnlyQueryEnvironment queryEnvironment, String type) {
    final IQueryBuilderEngine.AstResult result;

    if (type != null && type.length() > 0) {
        AstBuilderListener astBuilder = AQL56Compatibility
                .createAstBuilderListener((IQueryEnvironment) queryEnvironment);
        CharStream input = new UnbufferedCharStream(new StringReader(type), type.length());
        QueryLexer lexer = new QueryLexer(input);
        lexer.setTokenFactory(new CommonTokenFactory(true));
        lexer.removeErrorListeners();
        lexer.addErrorListener(astBuilder.getErrorListener());
        TokenStream tokens = new UnbufferedTokenStream<CommonToken>(lexer);
        QueryParser parser = new QueryParser(tokens);
        parser.addParseListener(astBuilder);
        parser.removeErrorListeners();
        parser.addErrorListener(astBuilder.getErrorListener());
        // parser.setTrace(true);
        parser.typeLiteral();
        result = astBuilder.getAstResult();
    } else {
        ErrorTypeLiteral errorTypeLiteral = (ErrorTypeLiteral) EcoreUtil
                .create(AstPackage.eINSTANCE.getErrorTypeLiteral());
        List<org.eclipse.acceleo.query.ast.Error> errors = new ArrayList<org.eclipse.acceleo.query.ast.Error>(1);
        errors.add(errorTypeLiteral);
        final Map<Object, Integer> positions = new HashMap<Object, Integer>();
        if (type != null) {
            positions.put(errorTypeLiteral, Integer.valueOf(0));
        }
        final BasicDiagnostic diagnostic = new BasicDiagnostic();
        diagnostic.add(new BasicDiagnostic(Diagnostic.ERROR, AstBuilderListener.PLUGIN_ID, 0, "null or empty type.",
                new Object[] {errorTypeLiteral }));
        result = new AstResult(errorTypeLiteral, positions, positions, errors, diagnostic);
    }

    return result;
}

private static AntrlResult getFromStream(final CharStream charStream) {

        final TSqlLexer lexer = new TSqlLexer(charStream);
        final CommonTokenStream stream = new CommonTokenStream(lexer);
        stream.fill();
        final TSqlParser parser = new TSqlParser(stream);

        AntrlResult result = new AntrlResult();
        result.setTree(parser.tsql_file());
        result.setStream(stream);
        result.setParser(parser);
        return result;
    }

public static void main(String[] args) {
    String someLangSourceCode = "a=10;\nb=20;\na * b";
    CharStream charStream = new ANTLRInputStream(someLangSourceCode);
    CalculatorLexer lexer = new CalculatorLexer(charStream);
    TokenStream tokens = new CommonTokenStream(lexer);
    CalculatorParser parser = new CalculatorParser(tokens);

    MyCalculatorVisitor visitor = new MyCalculatorVisitor();
    BigDecimal result = visitor.visit(parser.root());
    System.out.println(result);

}

public static void main(String[] args) {
    String someLangSourceCode = "1 + 2 - 3 + 4 * SUM(1,2,3,4,5,6,7,8,9,10) / 8";
    CharStream charStream = new ANTLRInputStream(someLangSourceCode);
    ExpressionLexer lexer = new ExpressionLexer(charStream);
    TokenStream tokens = new CommonTokenStream(lexer);
    ExpressionParser parser = new ExpressionParser(tokens);

    ItemExpressionVisitor visitor = new ItemExpressionVisitor();
    BigDecimal result = visitor.visit(parser.root());
    System.out.println(result);

}

@Override
public int LA(int i) {
    if (i == 0) {
        return 0;
    }
    if (i < 0) {
        i++; // e.g., translate LA(-1) to use offset 0
    }

    if ((p + i - 1) >= n) {
        return CharStream.EOF;
    }
    return Character.toLowerCase(data[p + i - 1]);
}

@Override
public int LA(int i) {
    if (i == 0) {
        return 0;
    }
    if (i < 0) {
        i++; // e.g., translate LA(-1) to use offset 0
    }

    if ((p + i - 1) >= n) {
        return CharStream.EOF;
    }
    return Character.toLowerCase(data[p + i - 1]);
}

public ConditionValidator(Map<String, FieldValidatorImpl> fieldValidatorMap, String id, String name, String expression, String error) {
    super(id);
    this.fieldValidatorMap = fieldValidatorMap;
    this.expression = expression;
    this.error = error;
    final CharStream charStream = new ANTLRInputStream(expression);
    logger.info("Constructing new lexer and parser for expression " + expression);
    checklistConditionLexer = new ChecklistConditionLexer(charStream);
    final CommonTokenStream commonTokenStream = new CommonTokenStream(checklistConditionLexer);
    checklistConditionParser = new ChecklistConditionParser(commonTokenStream);
}

public void query(ChannelHandlerContext ctx, QueryPacket packet) throws Exception {
    CharStream sql= packet.getSql();
    Object result = null;
    if (sql == null) {
        serverHandler.writeErrMessage(ctx, MysqlErrorCode.ER_ERROR_WHEN_EXECUTING_COMMAND, "Empty query.");
    } 
    else {
        result = serverHandler.session.run(sql);
        Helper.writeResonpse(ctx, serverHandler, result, true);
    }
}

private Integer asyncInsert(CharStream cs) {
    if (this.asyncExecutor.getError() != null) {
        throw new OrcaException(this.asyncExecutor.getError());
    }
    this.asyncExecutor.add(cs);
    return 1;
}

@Override
public Script parse(Session session, CharStream cs) {
    ScriptContext scriptCtx = parse(cs);
    GeneratorContext ctx = new GeneratorContext(session);
    InstructionGenerator.scan(ctx, scriptCtx);
    Instruction code = (Instruction)InstructionGenerator.generate(ctx, scriptCtx);
    Script script = new Script(code, ctx.getParameterCount(), ctx.getVariableCount(), cs.toString());
    return script;
}

@Override
public Object run(VdmContext ctx, Parameters params, CharStream cs) {
       ScriptContext rule = parse(cs);
       GeneratorContext gctx = new GeneratorContext(ctx.getSession());
       gctx.setCompileDdl(true);
       InstructionGenerator.scan(gctx, rule);
       Object result = run(gctx, ctx, params, rule);
       return result;
}