001    /*
002     * Copyright (c) 2005 Einar Pehrson <einar@pehrson.nu>.
003     *
004     * This file is part of
005     * CleanSheets - a spreadsheet application for the Java platform.
006     *
007     * CleanSheets is free software; you can redistribute it and/or modify
008     * it under the terms of the GNU General Public License as published by
009     * the Free Software Foundation; either version 2 of the License, or
010     * (at your option) any later version.
011     *
012     * CleanSheets is distributed in the hope that it will be useful,
013     * but WITHOUT ANY WARRANTY; without even the implied warranty of
014     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
015     * GNU General Public License for more details.
016     *
017     * You should have received a copy of the GNU General Public License
018     * along with CleanSheets; if not, write to the Free Software
019     * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
020     */
021    package csheets.core.formula.lang;
022    
023    import csheets.core.IllegalValueTypeException;
024    import csheets.core.Value;
025    import csheets.core.formula.BinaryOperator;
026    import csheets.core.formula.Expression;
027    
028    /**
029     * An adder.
030     * @author Einar Pehrson
031     */
032    public class Adder implements BinaryOperator {
033    
034            /** The unique version identifier used for serialization */
035            private static final long serialVersionUID = -1880245696016234963L;
036    
037            /**
038             * Creates a new adder.
039             */
040            public Adder() {}
041    
042            public Value applyTo(Expression leftOperand, Expression rightOperand) throws IllegalValueTypeException {
043                    return new Value(leftOperand.evaluate().toDouble()
044                                    + rightOperand.evaluate().toDouble());
045            }
046    
047            public String getIdentifier() {
048                    return "+";
049            }
050    
051            public Value.Type getOperandValueType() {
052                    return Value.Type.NUMERIC;
053            }
054    
055            public String toString() {
056                    return getIdentifier();
057            }
058    }