/*******************************************************************************
* SAT4J: a SATisfiability library for Java Copyright (C) 2004-2008 Daniel Le Berre
*
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU Lesser General Public License Version 2.1 or later (the
* "LGPL"), in which case the provisions of the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of the LGPL, and not to allow others to use your version of
* this file under the terms of the EPL, indicate your decision by deleting
* the provisions above and replace them with the notice and other provisions
* required by the LGPL. If you do not delete the provisions above, a recipient
* may use your version of this file under the terms of the EPL or the LGPL.
* 
* Based on the original MiniSat specification from:
* 
* An extensible SAT solver. Niklas Een and Niklas Sorensson. Proceedings of the
* Sixth International Conference on Theory and Applications of Satisfiability
* Testing, LNCS 2919, pp 502-518, 2003.
*
* See www.minisat.se for the original solver in C++.
* 
*******************************************************************************/
package org.sat4j.tools;

import java.util.Iterator;

import org.sat4j.core.Vec;
import org.sat4j.specs.IConstr;
import org.sat4j.specs.ISolver;
import org.sat4j.specs.IVec;

/**
 * A utility class used to manage easily group of clauses to be deleted at some 
 * point in the solver.
 * 
 * @author dlb
 * @since 2.0
 *
 */
public class ConstrGroup {

	private final IVec<IConstr> constrs = new Vec<IConstr>();

	public void add(IConstr constr) {
		if (constr == null) {
			throw new IllegalArgumentException("The constraint you entered cannot be removed from the solver.");
		}
		constrs.push(constr);
	}

	public void clear()  {
		constrs.clear();
	}
	
	public void removeFrom(ISolver solver) {
		for (Iterator<IConstr> it = constrs.iterator(); it.hasNext();) {
			solver.removeConstr(it.next());
		}
	}
}