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: IfFunctionDescription.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    import org.jfree.formula.typing.coretypes.AnyType;
038    
039    /**
040     * Creation-Date: 04.11.2006, 18:28:55
041     * 
042     * @author Thomas Morgner
043     */
044    public class IfFunctionDescription extends AbstractFunctionDescription
045    {
046      public IfFunctionDescription()
047      {
048        super("org.jfree.formula.function.logical.If-Function");
049      }
050    
051      public int getParameterCount()
052      {
053        return 3;
054      }
055    
056      public Type getParameterType(final int position)
057      {
058        if (position == 0)
059        {
060          return LogicalType.TYPE;
061        }
062        else
063        {
064          return AnyType.TYPE;
065        }
066      }
067    
068      public Type getValueType()
069      {
070        return AnyType.TYPE;
071      }
072    
073      /**
074       * Defines, whether the parameter at the given position is mandatory. A
075       * mandatory parameter must be filled in, while optional parameters need not
076       * to be filled in.
077       * 
078       * @return
079       */
080      public boolean isParameterMandatory(final int position)
081      {
082        if (position == 1 || position == 2)
083        {
084          return true;
085        }
086        else
087        {
088          return false;
089        }
090      }
091    
092      /**
093       * Returns the default value for an optional parameter. If the value returned
094       * here is null, then this either means, that the parameter is mandatory or
095       * that the default value is computed by the expression itself.
096       * 
097       * @param position
098       * @return
099       */
100      public Object getDefaultValue(final int position)
101      {
102        return null;
103      }
104    
105      public FunctionCategory getCategory()
106      {
107        return LogicalFunctionCategory.CATEGORY;
108      }
109    
110    }