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The ANTLR 4 Runtime
There is a newer version: 4.13.2
/*
 * [The "BSD license"]
 *  Copyright (c) 2012 Terence Parr
 *  Copyright (c) 2012 Sam Harwell
 *  All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *
 *  1. Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *  2. Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *  3. The name of the author may not be used to endorse or promote products
 *     derived from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 *  IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 *  OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 *  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 *  NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 *  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 *  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

package org.antlr.v4.runtime.atn;

public final class EpsilonTransition extends Transition {

	private final int outermostPrecedenceReturn;

	public EpsilonTransition(ATNState target) {
		this(target, -1);
	}

	public EpsilonTransition(ATNState target, int outermostPrecedenceReturn) {
		super(target);
		this.outermostPrecedenceReturn = outermostPrecedenceReturn;
	}

	/**
	 * @return the rule index of a precedence rule for which this transition is
	 * returning from, where the precedence value is 0; otherwise, -1.
	 *
	 * @see ATNConfig#isPrecedenceFilterSuppressed()
	 * @see ParserATNSimulator#applyPrecedenceFilter(ATNConfigSet)
	 * @since 4.4.1
	 */
	public int outermostPrecedenceReturn() {
		return outermostPrecedenceReturn;
	}

	@Override
	public int getSerializationType() {
		return EPSILON;
	}

	@Override
	public boolean isEpsilon() { return true; }

	@Override
	public boolean matches(int symbol, int minVocabSymbol, int maxVocabSymbol) {
		return false;
	}

	@Override

	public String toString() {
		return "epsilon";
	}
}