Source for org.jfree.formula.function.logical.IfFunctionDescription

   1: /**
   2:  * =========================================
   3:  * LibFormula : a free Java formula library
   4:  * =========================================
   5:  *
   6:  * Project Info:  http://reporting.pentaho.org/libformula/
   7:  *
   8:  * (C) Copyright 2006-2007, by Pentaho Corporation and Contributors.
   9:  *
  10:  * This library is free software; you can redistribute it and/or modify it under the terms
  11:  * of the GNU Lesser General Public License as published by the Free Software Foundation;
  12:  * either version 2.1 of the License, or (at your option) any later version.
  13:  *
  14:  * This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
  15:  * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  16:  * See the GNU Lesser General Public License for more details.
  17:  *
  18:  * You should have received a copy of the GNU Lesser General Public License along with this
  19:  * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  20:  * Boston, MA 02111-1307, USA.
  21:  *
  22:  * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
  23:  * in the United States and other countries.]
  24:  *
  25:  *
  26:  * ------------
  27:  * $Id: IfFunctionDescription.java,v 1.5 2007/05/07 23:00:38 mimil Exp $
  28:  * ------------
  29:  * (C) Copyright 2006-2007, by Pentaho Corporation.
  30:  */
  31: package org.jfree.formula.function.logical;
  32: 
  33: import org.jfree.formula.function.AbstractFunctionDescription;
  34: import org.jfree.formula.function.FunctionCategory;
  35: import org.jfree.formula.typing.Type;
  36: import org.jfree.formula.typing.coretypes.LogicalType;
  37: import org.jfree.formula.typing.coretypes.AnyType;
  38: 
  39: /**
  40:  * Creation-Date: 04.11.2006, 18:28:55
  41:  * 
  42:  * @author Thomas Morgner
  43:  */
  44: public class IfFunctionDescription extends AbstractFunctionDescription
  45: {
  46:   public IfFunctionDescription()
  47:   {
  48:     super("org.jfree.formula.function.logical.If-Function");
  49:   }
  50: 
  51:   public int getParameterCount()
  52:   {
  53:     return 3;
  54:   }
  55: 
  56:   public Type getParameterType(int position)
  57:   {
  58:     if (position == 0)
  59:     {
  60:       return LogicalType.TYPE;
  61:     }
  62:     else
  63:     {
  64:       return AnyType.TYPE;
  65:     }
  66:   }
  67: 
  68:   public Type getValueType()
  69:   {
  70:     return AnyType.TYPE;
  71:   }
  72: 
  73:   /**
  74:    * Defines, whether the parameter at the given position is mandatory. A
  75:    * mandatory parameter must be filled in, while optional parameters need not
  76:    * to be filled in.
  77:    * 
  78:    * @return
  79:    */
  80:   public boolean isParameterMandatory(int position)
  81:   {
  82:     if (position == 1 || position == 2)
  83:     {
  84:       return true;
  85:     }
  86:     else
  87:     {
  88:       return false;
  89:     }
  90:   }
  91: 
  92:   /**
  93:    * Returns the default value for an optional parameter. If the value returned
  94:    * here is null, then this either means, that the parameter is mandatory or
  95:    * that the default value is computed by the expression itself.
  96:    * 
  97:    * @param position
  98:    * @return
  99:    */
 100:   public Object getDefaultValue(int position)
 101:   {
 102:     return null;
 103:   }
 104: 
 105:   public FunctionCategory getCategory()
 106:   {
 107:     return LogicalFunctionCategory.CATEGORY;
 108:   }
 109: 
 110: }