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.Expression;
026    import csheets.core.formula.Function;
027    import csheets.core.formula.FunctionParameter;
028    
029    /**
030     * A function that returns true if and only if all of its arguments are true.
031     * @author Einar Pehrson
032     */
033    public class And implements Function {
034    
035            /** The only (but repeatable) parameter: a boolean expression */
036            public static final FunctionParameter[] parameters = new FunctionParameter[] {
037                    new FunctionParameter(Value.Type.BOOLEAN, "Boolean expression", false,
038                            "A boolean expression to include")
039            };
040    
041            /**
042             * Creates a new instance of the AND function.
043             */
044            public And() {}
045    
046            public String getIdentifier() {
047                    return "AND";
048            }
049    
050            public Value applyTo(Expression[] arguments) throws IllegalValueTypeException {
051                    for (Expression argument : arguments)
052                            if (!argument.evaluate().toBoolean())
053                                    return new Value(false);
054                    return new Value(true);
055            }
056    
057            public FunctionParameter[] getParameters() {
058                    return parameters;
059            }
060    
061            public boolean isVarArg() {
062                    return true;
063            }
064    }