Source for org.jfree.formula.function.math.OddFunction

   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: OddFunction.java,v 1.2 2007/05/18 14:36:57 mimil Exp $
  28:  * ------------
  29:  * (C) Copyright 2006-2007, by Pentaho Corporation.
  30:  */
  31: package org.jfree.formula.function.math;
  32: 
  33: import org.jfree.formula.EvaluationException;
  34: import org.jfree.formula.FormulaContext;
  35: import org.jfree.formula.LibFormulaErrorValue;
  36: import org.jfree.formula.function.Function;
  37: import org.jfree.formula.function.ParameterCallback;
  38: import org.jfree.formula.lvalues.TypeValuePair;
  39: import org.jfree.formula.typing.Type;
  40: import org.jfree.formula.typing.coretypes.NumberType;
  41: 
  42: /**
  43:  * This function returns the rounding a number up to the nearest odd integer,
  44:  * where "up" means "away from 0".
  45:  * 
  46:  * @author Cedric Pronzato
  47:  * 
  48:  */
  49: public class OddFunction implements Function
  50: {
  51: 
  52:   public OddFunction()
  53:   {
  54:   }
  55: 
  56:   public TypeValuePair evaluate(FormulaContext context,
  57:       ParameterCallback parameters) throws EvaluationException
  58:   {
  59:     final int parameterCount = parameters.getParameterCount();
  60:     if (parameterCount < 1)
  61:     {
  62:       throw new EvaluationException(LibFormulaErrorValue.ERROR_ARGUMENTS_VALUE);
  63:     }
  64:     final Type type1 = parameters.getType(0);
  65:     final Object value1 = parameters.getValue(0);
  66:     final Number result = context.getTypeRegistry().convertToNumber(type1,
  67:         value1);
  68: 
  69:     final int intValue = result.intValue();
  70:     Integer ret = null;
  71: 
  72:     int test = intValue;
  73:     if (intValue < 0)
  74:     {
  75:       test = intValue * -1;
  76:     }
  77: 
  78:     if (test % 2 == 1)
  79:     {
  80:       ret = new Integer(intValue);
  81:     }
  82:     else
  83:     {
  84:       if (result.doubleValue() < 0)
  85:       {
  86:         ret = new Integer(intValue - 1);
  87:       }
  88:       else
  89:       {
  90:         ret = new Integer(intValue + 1);
  91:       }
  92:     }
  93: 
  94:     return new TypeValuePair(NumberType.GENERIC_NUMBER, ret);
  95:   }
  96: 
  97:   public String getCanonicalName()
  98:   {
  99:     return "ODD";
 100:   }
 101: 
 102: }