Examples with ParseTreeWalker org.antlr.v4.runtime.tree.ParseTreeWalker used on opensource projects

Example 1 with ParseTreeWalker

use of org.antlr.v4.runtime.tree.ParseTreeWalker in project pinot by linkedin.

the class Pql2Compiler method compileToBrokerRequest.

@Override
public BrokerRequest compileToBrokerRequest(String expression) throws Pql2CompilationException {
    try {
        //
        CharStream charStream = new ANTLRInputStream(expression);
        PQL2Lexer lexer = new PQL2Lexer(charStream);
        lexer.setTokenFactory(new CommonTokenFactory(true));
        TokenStream tokenStream = new UnbufferedTokenStream<CommonToken>(lexer);
        PQL2Parser parser = new PQL2Parser(tokenStream);
        parser.setErrorHandler(new BailErrorStrategy());
        // Parse
        ParseTree parseTree = parser.root();
        ParseTreeWalker walker = new ParseTreeWalker();
        Pql2AstListener listener = new Pql2AstListener(expression);
        walker.walk(listener, parseTree);
        AstNode rootNode = listener.getRootNode();
        BrokerRequest brokerRequest = new BrokerRequest();
        rootNode.updateBrokerRequest(brokerRequest);
        return brokerRequest;
    } catch (Pql2CompilationException e) {
        throw e;
    } catch (Exception e) {
        throw new Pql2CompilationException(e.getMessage());
    }
}

Example 2 with ParseTreeWalker

use of org.antlr.v4.runtime.tree.ParseTreeWalker in project incubator-systemml by apache.

the class PyDMLParserWrapper method doParse.

/**
	 * This function is supposed to be called directly only from PydmlSyntacticValidator when it encounters 'import'
	 * @param fileName script file name
	 * @param dmlScript script file contents
	 * @param sourceNamespace namespace from source statement
	 * @param argVals script arguments
	 * @return dml program, or null if at least one error
	 * @throws ParseException if ParseException occurs
	 */
public DMLProgram doParse(String fileName, String dmlScript, String sourceNamespace, Map<String, String> argVals) throws ParseException {
    DMLProgram dmlPgm = null;
    ANTLRInputStream in;
    try {
        if (dmlScript == null) {
            dmlScript = readDMLScript(fileName, LOG);
        }
        InputStream stream = new ByteArrayInputStream(dmlScript.getBytes());
        in = new org.antlr.v4.runtime.ANTLRInputStream(stream);
    } catch (FileNotFoundException e) {
        throw new ParseException("Cannot find file/resource: " + fileName, e);
    } catch (IOException e) {
        throw new ParseException("Cannot open file: " + fileName, e);
    } catch (LanguageException e) {
        throw new ParseException(e.getMessage(), e);
    }
    ProgramrootContext ast = null;
    CustomErrorListener errorListener = new CustomErrorListener();
    try {
        PydmlLexer lexer = new PydmlLexer(in);
        CommonTokenStream tokens = new CommonTokenStream(lexer);
        PydmlParser antlr4Parser = new PydmlParser(tokens);
        // For now no optimization, since it is not able to parse integer value. 
        boolean tryOptimizedParsing = false;
        if (tryOptimizedParsing) {
            // Try faster and simpler SLL
            antlr4Parser.getInterpreter().setPredictionMode(PredictionMode.SLL);
            antlr4Parser.removeErrorListeners();
            antlr4Parser.setErrorHandler(new BailErrorStrategy());
            try {
                ast = antlr4Parser.programroot();
            // If successful, no need to try out full LL(*) ... SLL was enough
            } catch (ParseCancellationException ex) {
                // Error occurred, so now try full LL(*) for better error messages
                tokens.reset();
                antlr4Parser.reset();
                if (fileName != null) {
                    errorListener.setCurrentFileName(fileName);
                } else {
                    errorListener.setCurrentFileName("MAIN_SCRIPT");
                }
                // Set our custom error listener
                antlr4Parser.addErrorListener(errorListener);
                antlr4Parser.setErrorHandler(new DefaultErrorStrategy());
                antlr4Parser.getInterpreter().setPredictionMode(PredictionMode.LL);
                ast = antlr4Parser.programroot();
            }
        } else {
            // Set our custom error listener
            antlr4Parser.removeErrorListeners();
            antlr4Parser.addErrorListener(errorListener);
            errorListener.setCurrentFileName(fileName);
            // Now do the parsing
            ast = antlr4Parser.programroot();
        }
    } catch (Exception e) {
        throw new ParseException("ERROR: Cannot parse the program:" + fileName, e);
    }
    // Now convert the parse tree into DMLProgram
    // Do syntactic validation while converting 
    ParseTree tree = ast;
    // And also do syntactic validation
    ParseTreeWalker walker = new ParseTreeWalker();
    // Get list of function definitions which take precedence over built-in functions if same name
    PydmlPreprocessor prep = new PydmlPreprocessor(errorListener);
    walker.walk(prep, tree);
    // Syntactic validation
    PydmlSyntacticValidator validator = new PydmlSyntacticValidator(errorListener, argVals, sourceNamespace, prep.getFunctionDefs());
    walker.walk(validator, tree);
    errorListener.unsetCurrentFileName();
    this.parseIssues = errorListener.getParseIssues();
    this.atLeastOneWarning = errorListener.isAtLeastOneWarning();
    this.atLeastOneError = errorListener.isAtLeastOneError();
    if (atLeastOneError) {
        throw new ParseException(parseIssues, dmlScript);
    }
    if (atLeastOneWarning) {
        LOG.warn(CustomErrorListener.generateParseIssuesMessage(dmlScript, parseIssues));
    }
    dmlPgm = createDMLProgram(ast, sourceNamespace);
    return dmlPgm;
}

Example 3 with ParseTreeWalker

use of org.antlr.v4.runtime.tree.ParseTreeWalker in project druid by druid-io.

the class Parser method parse.

public static Expr parse(String in, boolean withFlatten) {
    ExprLexer lexer = new ExprLexer(new ANTLRInputStream(in));
    CommonTokenStream tokens = new CommonTokenStream(lexer);
    ExprParser parser = new ExprParser(tokens);
    parser.setBuildParseTree(true);
    ParseTree parseTree = parser.expr();
    ParseTreeWalker walker = new ParseTreeWalker();
    ExprListenerImpl listener = new ExprListenerImpl(parseTree);
    walker.walk(listener, parseTree);
    return withFlatten ? flatten(listener.getAST()) : listener.getAST();
}

Example 4 with ParseTreeWalker

use of org.antlr.v4.runtime.tree.ParseTreeWalker in project pinot by linkedin.

the class Pql2Compiler method compileToExpressionTree.

@Override
public TransformExpressionTree compileToExpressionTree(String expression) {
    CharStream charStream = new ANTLRInputStream(expression);
    PQL2Lexer lexer = new PQL2Lexer(charStream);
    lexer.setTokenFactory(new CommonTokenFactory(true));
    TokenStream tokenStream = new UnbufferedTokenStream<CommonToken>(lexer);
    PQL2Parser parser = new PQL2Parser(tokenStream);
    parser.setErrorHandler(new BailErrorStrategy());
    // Parse
    ParseTree parseTree = parser.expression();
    ParseTreeWalker walker = new ParseTreeWalker();
    Pql2AstListener listener = new Pql2AstListener(expression);
    walker.walk(listener, parseTree);
    final AstNode rootNode = listener.getRootNode();
    return TransformExpressionTree.buildTree(rootNode);
}

Example 5 with ParseTreeWalker

use of org.antlr.v4.runtime.tree.ParseTreeWalker in project antlr4 by antlr.

the class BaseCppTest method writeParserTestFile.

protected void writeParserTestFile(String parserName, String lexerName, String listenerName, String visitorName, String parserStartRuleName, boolean debug, boolean trace) {
    if (!parserStartRuleName.endsWith(")"))
        parserStartRuleName += "()";
    ST outputFileST = new ST("#include \\<iostream>\n" + "\n" + "#include \"antlr4-runtime.h\"\n" + "#include \"<lexerName>.h\"\n" + "#include \"<parserName>.h\"\n" + "\n" + "using namespace antlr4;\n" + "\n" + "class TreeShapeListener : public tree::ParseTreeListener {\n" + "public:\n" + "  void visitTerminal(tree::TerminalNode *) override {}\n" + "  void visitErrorNode(tree::ErrorNode *) override {}\n" + "  void exitEveryRule(ParserRuleContext *) override {}\n" + "  void enterEveryRule(ParserRuleContext *ctx) override {\n" + "    for (auto child : ctx->children) {\n" + "      tree::ParseTree *parent = child->parent;\n" + "      ParserRuleContext *rule = dynamic_cast\\<ParserRuleContext *>(parent);\n" + "      if (rule != ctx) {\n" + "        throw \"Invalid parse tree shape detected.\";\n" + "      }\n" + "    }\n" + "  }\n" + "};\n" + "\n" + "\n" + "int main(int argc, const char* argv[]) {\n" + "  ANTLRFileStream input(argv[1]);\n" + "  <lexerName> lexer(&input);\n" + "  CommonTokenStream tokens(&lexer);\n" + "<createParser>" + "\n" + "  tree::ParseTree *tree = parser.<parserStartRuleName>;\n" + "  TreeShapeListener listener;\n" + "  tree::ParseTreeWalker::DEFAULT.walk(&listener, tree);\n" + "\n" + "  return 0;\n" + "}\n");
    String stSource = "  <parserName> parser(&tokens);\n";
    if (debug) {
        stSource += "  DiagnosticErrorListener errorListener;\n";
        stSource += "  parser.addErrorListener(&errorListener);\n";
    }
    if (trace)
        stSource += "  parser.setTrace(true);\n";
    ST createParserST = new ST(stSource);
    outputFileST.add("createParser", createParserST);
    outputFileST.add("parserName", parserName);
    outputFileST.add("lexerName", lexerName);
    outputFileST.add("listenerName", listenerName);
    outputFileST.add("visitorName", visitorName);
    outputFileST.add("parserStartRuleName", parserStartRuleName);
    writeFile(tmpdir, "Test.cpp", outputFileST.render());
}