ChoicePointContext.java

/*
 * tuProlog - Copyright (C) 2001-2002  aliCE team at deis.unibo.it
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
package alice.tuprolog;

import java.util.ArrayList;
import java.util.List;

/**
 * 
 * @author Alex Benini
 */
public class ChoicePointContext {
	
	ClauseStore compatibleGoals;
	ExecutionContext executionContext;
	ChoicePointContext prevChoicePointContext;
	
	SubGoalId indexSubGoal;
	OneWayList<List<Var>> varsToDeunify;
	
	@Override
	public String toString() {
		return "     ChoicePointId: " + executionContext.getId() + ":" + indexSubGoal + "\n" +
			   //"varsToDeunify: " + getVarsToDeunify() + "\n" +
			   "     compGoals:     " + compatibleGoals + "\n";
	}
	
	/*
	 * Methods for spyListeners
	 */
	
	public ClauseStore getCompatibleGoals() {
		return compatibleGoals;
	}
	
	public ExecutionContext getExecutionContext() {
		return executionContext;
	}
	
	public SubGoalId getIndexBack() {
		return indexSubGoal;
	}
	
	public List<List<Var>> getVarsToDeunify() {
		List<List<Var>> l = new ArrayList<List<Var>>();
		OneWayList<List<Var>> t = varsToDeunify;
		while (t != null) {
			l.add(t.getHead());
			t = t.getTail();
		}
		return l;
	}
	
}