Application: gvSIG desktop » Library: org.gvsig.tools

/* gvSIG. Geographic Information System of the Valencian Government

 *

 * Copyright (C) 2007-2008 Infrastructures and Transports Department

 * of the Valencian Government (CIT)

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version 2

 * of the License, or (at your option) any later version.

 *

 * This program 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 General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,

 * MA  02110-1301, USA.

 *

 */

package org.gvsig.tools.evaluator;

import java.util.ArrayList;

import java.util.List;

/**

 * <p>

 * This evaluator is a set of evaluators that are applied used the and

 * operator. It means that the evaluate method only returns <code>true</code>

 * if all the evaluators return <code>true</code>.  

 * </p>

 * <p>

 * A condition to use this type of evaluators is that the evaluate method

 * of all the single evaluators has to return a boolean value.

 * </p>

 * 

 * @author gvSIG Team

 * @version $Id$

 * 

 */

public class AndEvaluator extends AbstractEvaluator{

    private List evaluators = new ArrayList();    

    public AndEvaluator(Evaluator evaluator) {

        super();         

        addEvaluator(evaluator);    

    }

    public Object evaluate(EvaluatorData data) throws EvaluatorException {

        for (int i=0 ; i<evaluators.size() ; i++){

            Evaluator evaluator = (Evaluator)evaluators.get(i);

            if (!((Boolean)evaluator.evaluate(data)).booleanValue()){

                return new Boolean(false);

            }

        }

        return new Boolean(true);

    }

    public String getName() {       

        return "a set of evaluators";

    }

    public void addEvaluator(Evaluator evaluator){

        if (evaluator != null){

            evaluators.add(evaluator);

        }

    }

    public String getSQL() {       

        if (evaluators.size() > 0){

            String sql = ((Evaluator)evaluators.get(0)).getSQL();

            for (int i=1 ; i<evaluators.size() ; i++){

                sql = sql + " and " + ((Evaluator)evaluators.get(i)).getSQL();

            }

            return sql;

        }else{

            return "";

        }

    }   

}