001    /**
002     * =========================================
003     * LibFormula : a free Java formula library
004     * =========================================
005     *
006     * Project Info:  http://reporting.pentaho.org/libformula/
007     *
008     * (C) Copyright 2006-2007, by Pentaho Corporation and Contributors.
009     *
010     * This library is free software; you can redistribute it and/or modify it under the terms
011     * of the GNU Lesser General Public License as published by the Free Software Foundation;
012     * either version 2.1 of the License, or (at your option) any later version.
013     *
014     * This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
015     * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
016     * See the GNU Lesser General Public License for more details.
017     *
018     * You should have received a copy of the GNU Lesser General Public License along with this
019     * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
020     * Boston, MA 02111-1307, USA.
021     *
022     * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
023     * in the United States and other countries.]
024     *
025     *
026     * ------------
027     * $Id: TrueFunctionDescription.java 3521 2007-10-16 10:55:14Z tmorgner $
028     * ------------
029     * (C) Copyright 2006-2007, by Pentaho Corporation.
030     */
031    package org.jfree.formula.function.logical;
032    
033    import org.jfree.formula.function.AbstractFunctionDescription;
034    import org.jfree.formula.function.FunctionCategory;
035    import org.jfree.formula.typing.Type;
036    import org.jfree.formula.typing.coretypes.LogicalType;
037    
038    /**
039     * Creation-Date: 04.11.2006, 18:28:55
040     *
041     * @author Thomas Morgner
042     */
043    public class TrueFunctionDescription extends AbstractFunctionDescription
044    {
045      public TrueFunctionDescription()
046      {
047        super("org.jfree.formula.function.logical.True-Function");
048      }
049    
050      public int getParameterCount()
051      {
052        return 0;
053      }
054    
055      public boolean isInfiniteParameterCount()
056      {
057        return false;
058      }
059    
060      public Type getParameterType(final int position)
061      {
062        return LogicalType.TYPE;
063      }
064    
065      public Type getValueType()
066      {
067        return LogicalType.TYPE;
068      }
069    
070      /**
071       * Defines, whether the parameter at the given position is mandatory. A
072       * mandatory parameter must be filled in, while optional parameters need not
073       * to be filled in.
074       *
075       * @return
076       */
077      public boolean isParameterMandatory(final int position)
078      {
079        return false;
080      }
081    
082      /**
083       * Returns the default value for an optional parameter. If the value returned
084       * here is null, then this either means, that the parameter is mandatory or
085       * that the default value is computed by the expression itself.
086       *
087       * @param position
088       * @return
089       */
090      public Object getDefaultValue(final int position)
091      {
092        return null;
093      }
094    
095      public FunctionCategory getCategory()
096      {
097        return LogicalFunctionCategory.CATEGORY;
098      }
099    
100    }