Source for org.jfree.formula.operators.PercentageOperator

   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: PercentageOperator.java 2887 2007-06-06 17:07:52Z taqua $
  28:  * ------------
  29:  * (C) Copyright 2006-2007, by Pentaho Corporation.
  30:  */
  31: package org.jfree.formula.operators;
  32: 
  33: import java.math.BigDecimal;
  34: 
  35: import org.jfree.formula.EvaluationException;
  36: import org.jfree.formula.FormulaContext;
  37: import org.jfree.formula.LibFormulaErrorValue;
  38: import org.jfree.formula.lvalues.TypeValuePair;
  39: import org.jfree.formula.typing.Type;
  40: import org.jfree.formula.typing.TypeRegistry;
  41: 
  42: /**
  43:  * Creation-Date: 02.11.2006, 10:27:03
  44:  *
  45:  * @author Thomas Morgner
  46:  */
  47: public class PercentageOperator implements PostfixOperator
  48: {
  49:   private static final BigDecimal HUNDRED = new BigDecimal(100);
  50: 
  51: 
  52:   public PercentageOperator()
  53:   {
  54:   }
  55: 
  56: 
  57:   public TypeValuePair evaluate(final FormulaContext context, final TypeValuePair value1)
  58:       throws EvaluationException
  59:   {
  60:     final Object rawValue = value1.getValue();
  61:     if (rawValue == null)
  62:     {
  63:       throw new EvaluationException(LibFormulaErrorValue.ERROR_NA_VALUE);
  64:     }
  65: 
  66:     final Type type = value1.getType();
  67:     final TypeRegistry typeRegistry = context.getTypeRegistry();
  68: 
  69:     if (type.isFlagSet(Type.NUMERIC_TYPE) == false &&
  70:         type.isFlagSet(Type.ANY_TYPE) == false)
  71:     {
  72:       throw new EvaluationException(LibFormulaErrorValue.ERROR_INVALID_ARGUMENT_VALUE);
  73:     }
  74: 
  75:     // return the same as zero minus value.
  76:     final Number number = typeRegistry.convertToNumber(type, rawValue);
  77:     final BigDecimal value = OperatorUtility.getAsBigDecimal(number);
  78:     final BigDecimal divide = value.divide(HUNDRED, value.scale()+2,BigDecimal.ROUND_HALF_UP);
  79:     return new TypeValuePair(type, divide);
  80:   }
  81: 
  82:   public String toString()
  83:   {
  84:     return "%";
  85:   }
  86: 
  87: }
  88: