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;
022    
023    import csheets.core.Value;
024    import csheets.core.formula.util.ExpressionVisitor;
025    
026    /**
027     * A literal value in a formula.
028     * @author Einar Pehrson
029     */
030    public class Literal implements Expression {
031    
032            /** The unique version identifier used for serialization */
033            private static final long serialVersionUID = 7854180857828149858L;
034    
035            /** The value of the literal */
036            private Value value;
037    
038            /**
039             * Creates a new literal.
040             * @param value the value of literal
041             */
042            public Literal(Value value) {
043                    this.value = value;
044            }
045    
046            public Value evaluate() {
047                    return value;
048            }
049    
050            /**
051             * Returns the value of the literal.
052             * @return the value of the literal
053             */
054            public Value getValue() {
055                    return value;
056            }
057    
058            public Object accept(ExpressionVisitor visitor) {
059                    return visitor.visitLiteral(this);
060            }
061    
062            public String toString() {
063                    if (value.getType() == Value.Type.TEXT
064                     || value.getType() == Value.Type.DATE)
065                            return "\"" + value.toString() + "\"";
066                    else
067                            return value.toString();
068            }
069    }