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

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Here is the source code for org.antlr.v4.runtime.LexerNoViableAltException.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;
import org.antlr.v4.runtime.misc.Interval;
import org.antlr.v4.runtime.misc.Utils;

import java.util.Locale;

public class LexerNoViableAltException extends RecognitionException {
    /** Matching attempted at what input index? */
    private final int startIndex;

    /** Which configurations did we try at input.index() that couldn't match input.LA(1)? */
    private final ATNConfigSet deadEndConfigs;

    public LexerNoViableAltException(Lexer lexer, CharStream input, int startIndex, ATNConfigSet deadEndConfigs) {
        super(lexer, input, null);
        this.startIndex = startIndex;
        this.deadEndConfigs = deadEndConfigs;
    }

    public int getStartIndex() {
        return startIndex;
    }

    public ATNConfigSet getDeadEndConfigs() {
        return deadEndConfigs;
    }

    @Override
    public CharStream getInputStream() {
        return (CharStream) super.getInputStream();
    }

    @Override
    public String toString() {
        String symbol = "";
        if (startIndex >= 0 && startIndex < getInputStream().size()) {
            symbol = getInputStream().getText(Interval.of(startIndex, startIndex));
            symbol = Utils.escapeWhitespace(symbol, false);
        }

        return String.format(Locale.getDefault(), "%s('%s')", LexerNoViableAltException.class.getSimpleName(),
                symbol);
    }
}