org.antlr.v4.runtime.NoViableAltException.java Source code

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Here is the source code for org.antlr.v4.runtime.NoViableAltException.java

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/*
 * Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
 * Use of this file is governed by the BSD 3-clause license that
 * can be found in the LICENSE.txt file in the project root.
 */
package org.antlr.v4.runtime;

import org.antlr.v4.runtime.atn.ATNConfigSet;

/** Indicates that the parser could not decide which of two or more paths
 *  to take based upon the remaining input. It tracks the starting token
 *  of the offending input and also knows where the parser was
 *  in the various paths when the error. Reported by reportNoViableAlternative()
 */
public class NoViableAltException extends RecognitionException {
    /** Which configurations did we try at input.index() that couldn't match input.LT(1)? */

    private final ATNConfigSet deadEndConfigs;

    /** The token object at the start index; the input stream might
     *    not be buffering tokens so get a reference to it. (At the
     *  time the error occurred, of course the stream needs to keep a
     *  buffer all of the tokens but later we might not have access to those.)
     */

    private final Token startToken;

    public NoViableAltException(Parser recognizer) { // LL(1) error
        this(recognizer, recognizer.getInputStream(), recognizer.getCurrentToken(), recognizer.getCurrentToken(),
                null, recognizer._ctx);
    }

    public NoViableAltException(Parser recognizer, TokenStream input, Token startToken, Token offendingToken,
            ATNConfigSet deadEndConfigs, ParserRuleContext ctx) {
        super(recognizer, input, ctx);
        this.deadEndConfigs = deadEndConfigs;
        this.startToken = startToken;
        this.setOffendingToken(offendingToken);
    }

    public Token getStartToken() {
        return startToken;
    }

    public ATNConfigSet getDeadEndConfigs() {
        return deadEndConfigs;
    }

}