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The ANTLR 4 grammar compiler.
There is a newer version: 4.9.0
/*
 * [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.codegen.model;

import org.antlr.v4.codegen.OutputModelFactory;
import org.antlr.v4.runtime.atn.StarLoopEntryState;
import org.antlr.v4.runtime.misc.IntervalSet;
import org.antlr.v4.tool.ast.GrammarAST;

import java.util.Arrays;
import java.util.List;

/** */
public class LL1StarBlock extends LL1Loop {
	/** Token names for each alt 0..n-1 */
	public List altLook;
	public String loopLabel;
	public String[] exitLook;

	public LL1StarBlock(OutputModelFactory factory, GrammarAST starRootAST, List alts) {
		super(factory, starRootAST, alts);

		StarLoopEntryState star = (StarLoopEntryState)starRootAST.atnState;
		blockStartStateNumber =
			starRootAST.atnState.transition(0).target.stateNumber;

		loopBackStateNumber = star.loopBackState.stateNumber;

		this.decision = star.decision;

		/** Lookahead for each alt 1..n */
		IntervalSet[] altLookSets = factory.getGrammar().decisionLOOK.get(decision);
		IntervalSet lastLook = altLookSets[altLookSets.length-1];
		// remove last (exit) alt
		altLookSets = Arrays.copyOf(altLookSets, altLookSets.length - 1);
		altLook = getAltLookaheadAsStringLists(altLookSets);
		loopLabel = factory.getGenerator().getTarget().getLoopLabel(starRootAST);

		this.exitLook =
			factory.getGenerator().getTarget().getTokenTypesAsTargetLabels(factory.getGrammar(), lastLook.toArray());
	}
}