Source for org.jfree.formula.function.information.IsErrFunction

   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: IsErrFunction.java 2887 2007-06-06 17:07:52Z taqua $
  28:  * ------------
  29:  * (C) Copyright 2006-2007, by Pentaho Corporation.
  30:  */
  31: package org.jfree.formula.function.information;
  32: 
  33: import org.jfree.formula.ErrorValue;
  34: import org.jfree.formula.EvaluationException;
  35: import org.jfree.formula.FormulaContext;
  36: import org.jfree.formula.LibFormulaErrorValue;
  37: import org.jfree.formula.function.Function;
  38: import org.jfree.formula.function.ParameterCallback;
  39: import org.jfree.formula.lvalues.TypeValuePair;
  40: import org.jfree.formula.typing.Type;
  41: import org.jfree.formula.typing.coretypes.ErrorType;
  42: import org.jfree.formula.typing.coretypes.LogicalType;
  43: import org.jfree.util.Log;
  44: 
  45: /**
  46:  * This function returns true if the parameter is of error and not of error type NA.
  47:  *
  48:  * @author Cedric Pronzato
  49:  */
  50: public class IsErrFunction implements Function
  51: {
  52: 
  53:   private static final TypeValuePair RETURN_TRUE = new TypeValuePair(LogicalType.TYPE, Boolean.TRUE);
  54:   private static final TypeValuePair RETURN_FALSE = new TypeValuePair(LogicalType.TYPE, Boolean.FALSE);
  55: 
  56:   public IsErrFunction()
  57:   {
  58:   }
  59: 
  60:   public TypeValuePair evaluate(final FormulaContext context,
  61:                                 final ParameterCallback parameters) throws EvaluationException
  62:   {
  63:     if (parameters.getParameterCount() != 1)
  64:     {
  65:       throw new EvaluationException(LibFormulaErrorValue.ERROR_ARGUMENTS_VALUE);
  66:     }
  67: 
  68:     try
  69:     {
  70:       final Type type = parameters.getType(0);
  71:       final Object value = parameters.getValue(0);
  72: 
  73:       if (ErrorType.TYPE.equals(type) && value instanceof ErrorValue)
  74:       {
  75:         Log.warn ("Passing errors around is deprecated. Throw exceptions instead.");
  76:         final ErrorValue na = (ErrorValue) value;
  77:         if (na.getErrorCode() == LibFormulaErrorValue.ERROR_NA)
  78:         {
  79:           return RETURN_FALSE;
  80:         }
  81:         else
  82:         {
  83:           return RETURN_TRUE;
  84:         }
  85:       }
  86:     }
  87:     catch (EvaluationException e)
  88:     {
  89:       if (e.getErrorValue().getErrorCode() == LibFormulaErrorValue.ERROR_NA)
  90:       {
  91:         return RETURN_FALSE;
  92:       }
  93:       else
  94:       {
  95:         return RETURN_TRUE;
  96:       }
  97:     }
  98: 
  99:     return RETURN_FALSE;
 100:   }
 101: 
 102:   public String getCanonicalName()
 103:   {
 104:     return "ISERR";
 105:   }
 106: 
 107: }