Examples with LexerNoViableAltException org.antlr.v4.runtime.LexerNoViableAltException used on opensource projects

Example 1 with LexerNoViableAltException

use of org.antlr.v4.runtime.LexerNoViableAltException in project antlr4 by tunnelvisionlabs.

the class XPath method split.

// TODO: check for invalid token/rule names, bad syntax
public XPathElement[] split(String path) {
    XPathLexer lexer = new XPathLexer(CharStreams.fromString(path)) {

        @Override
        public void recover(LexerNoViableAltException e) {
            throw e;
        }
    };
    lexer.removeErrorListeners();
    lexer.addErrorListener(new XPathLexerErrorListener());
    CommonTokenStream tokenStream = new CommonTokenStream(lexer);
    try {
        tokenStream.fill();
    } catch (LexerNoViableAltException e) {
        int pos = lexer.getCharPositionInLine();
        String msg = "Invalid tokens or characters at index " + pos + " in path '" + path + "'";
        throw new IllegalArgumentException(msg, e);
    }
    List<Token> tokens = tokenStream.getTokens();
    // System.out.println("path="+path+"=>"+tokens);
    List<XPathElement> elements = new ArrayList<XPathElement>();
    int n = tokens.size();
    int i = 0;
    loop: while (i < n) {
        Token el = tokens.get(i);
        Token next = null;
        switch(el.getType()) {
            case XPathLexer.ROOT:
            case XPathLexer.ANYWHERE:
                boolean anywhere = el.getType() == XPathLexer.ANYWHERE;
                i++;
                next = tokens.get(i);
                boolean invert = next.getType() == XPathLexer.BANG;
                if (invert) {
                    i++;
                    next = tokens.get(i);
                }
                XPathElement pathElement = getXPathElement(next, anywhere);
                pathElement.invert = invert;
                elements.add(pathElement);
                i++;
                break;
            case XPathLexer.TOKEN_REF:
            case XPathLexer.RULE_REF:
            case XPathLexer.WILDCARD:
                elements.add(getXPathElement(el, false));
                i++;
                break;
            case Token.EOF:
                break loop;
            default:
                throw new IllegalArgumentException("Unknowth path element " + el);
        }
    }
    return elements.toArray(new XPathElement[0]);
}

Example 2 with LexerNoViableAltException

use of org.antlr.v4.runtime.LexerNoViableAltException in project antlr4 by antlr.

the class XPath method split.

// TODO: check for invalid token/rule names, bad syntax
public XPathElement[] split(String path) {
    ANTLRInputStream in;
    try {
        in = new ANTLRInputStream(new StringReader(path));
    } catch (IOException ioe) {
        throw new IllegalArgumentException("Could not read path: " + path, ioe);
    }
    XPathLexer lexer = new XPathLexer(in) {

        @Override
        public void recover(LexerNoViableAltException e) {
            throw e;
        }
    };
    lexer.removeErrorListeners();
    lexer.addErrorListener(new XPathLexerErrorListener());
    CommonTokenStream tokenStream = new CommonTokenStream(lexer);
    try {
        tokenStream.fill();
    } catch (LexerNoViableAltException e) {
        int pos = lexer.getCharPositionInLine();
        String msg = "Invalid tokens or characters at index " + pos + " in path '" + path + "'";
        throw new IllegalArgumentException(msg, e);
    }
    List<Token> tokens = tokenStream.getTokens();
    // System.out.println("path="+path+"=>"+tokens);
    List<XPathElement> elements = new ArrayList<XPathElement>();
    int n = tokens.size();
    int i = 0;
    loop: while (i < n) {
        Token el = tokens.get(i);
        Token next = null;
        switch(el.getType()) {
            case XPathLexer.ROOT:
            case XPathLexer.ANYWHERE:
                boolean anywhere = el.getType() == XPathLexer.ANYWHERE;
                i++;
                next = tokens.get(i);
                boolean invert = next.getType() == XPathLexer.BANG;
                if (invert) {
                    i++;
                    next = tokens.get(i);
                }
                XPathElement pathElement = getXPathElement(next, anywhere);
                pathElement.invert = invert;
                elements.add(pathElement);
                i++;
                break;
            case XPathLexer.TOKEN_REF:
            case XPathLexer.RULE_REF:
            case XPathLexer.WILDCARD:
                elements.add(getXPathElement(el, false));
                i++;
                break;
            case Token.EOF:
                break loop;
            default:
                throw new IllegalArgumentException("Unknowth path element " + el);
        }
    }
    return elements.toArray(new XPathElement[0]);
}

Example 3 with LexerNoViableAltException

use of org.antlr.v4.runtime.LexerNoViableAltException in project antlr4 by antlr.

the class XPathLexer method nextToken.

@Override
public Token nextToken() {
    _tokenStartCharIndex = _input.index();
    CommonToken t = null;
    while (t == null) {
        switch(_input.LA(1)) {
            case '/':
                consume();
                if (_input.LA(1) == '/') {
                    consume();
                    t = new CommonToken(ANYWHERE, "//");
                } else {
                    t = new CommonToken(ROOT, "/");
                }
                break;
            case '*':
                consume();
                t = new CommonToken(WILDCARD, "*");
                break;
            case '!':
                consume();
                t = new CommonToken(BANG, "!");
                break;
            case '\'':
                String s = matchString();
                t = new CommonToken(STRING, s);
                break;
            case CharStream.EOF:
                return new CommonToken(EOF, "<EOF>");
            default:
                if (isNameStartChar(_input.LA(1))) {
                    String id = matchID();
                    if (Character.isUpperCase(id.charAt(0)))
                        t = new CommonToken(TOKEN_REF, id);
                    else
                        t = new CommonToken(RULE_REF, id);
                } else {
                    throw new LexerNoViableAltException(this, _input, _tokenStartCharIndex, null);
                }
                break;
        }
    }
    t.setStartIndex(_tokenStartCharIndex);
    t.setCharPositionInLine(_tokenStartCharIndex);
    t.setLine(line);
    return t;
}

Example 4 with LexerNoViableAltException

use of org.antlr.v4.runtime.LexerNoViableAltException in project elasticsearch by elastic.

the class EnhancedPainlessLexer method recover.

@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));
}

Example 5 with LexerNoViableAltException

use of org.antlr.v4.runtime.LexerNoViableAltException in project L42 by ElvisResearchGroup.

the class Parser method getParser.

public static antlrGenerated.L42Parser getParser(String s) {
    ANTLRInputStream in = new ANTLRInputStream(s);
    antlrGenerated.L42Lexer l = new antlrGenerated.L42Lexer(in);
    /*{
      @Override public void recover(LexerNoViableAltException e) {
        throw new IllegalArgumentException(e); // Bail out
      }
    @Override public void recover(RecognitionException re) {
        throw new IllegalArgumentException(re); // Bail out
      }};*/
    CommonTokenStream t = new CommonTokenStream(l);
    antlrGenerated.L42Parser p = new antlrGenerated.L42Parser(t);
    //    p.setErrorHandler(new BailErrorStrategy());
    return p;
}