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: IsNaFunction.java 2887 2007-06-06 17:07:52Z taqua $
028 * ------------
029 * (C) Copyright 2006-2007, by Pentaho Corporation.
030 */
031 package org.jfree.formula.function.information;
032
033 import org.jfree.formula.ErrorValue;
034 import org.jfree.formula.EvaluationException;
035 import org.jfree.formula.FormulaContext;
036 import org.jfree.formula.LibFormulaErrorValue;
037 import org.jfree.formula.function.Function;
038 import org.jfree.formula.function.ParameterCallback;
039 import org.jfree.formula.lvalues.TypeValuePair;
040 import org.jfree.formula.typing.Type;
041 import org.jfree.formula.typing.coretypes.ErrorType;
042 import org.jfree.formula.typing.coretypes.LogicalType;
043 import org.jfree.util.Log;
044
045 /**
046 * This function returns true if the parameter is of error type NA.
047 *
048 * @author Cedric Pronzato
049 */
050 public class IsNaFunction implements Function
051 {
052
053 private static final TypeValuePair RETURN_FALSE = new TypeValuePair(LogicalType.TYPE, Boolean.FALSE);
054 private static final TypeValuePair RETURN_TRUE = new TypeValuePair(LogicalType.TYPE, Boolean.TRUE);
055
056 public IsNaFunction()
057 {
058 }
059
060 public TypeValuePair evaluate(final FormulaContext context,
061 final ParameterCallback parameters) throws EvaluationException
062 {
063 if (parameters.getParameterCount() != 1)
064 {
065 throw new EvaluationException(LibFormulaErrorValue.ERROR_ARGUMENTS_VALUE);
066 }
067
068 try
069 {
070 final Type type = parameters.getType(0);
071 final Object value = parameters.getValue(0);
072
073 if (ErrorType.TYPE.equals(type) && value instanceof ErrorValue)
074 {
075 Log.warn ("Passing errors around is deprecated. Throw exceptions instead.");
076 final ErrorValue na = (ErrorValue) value;
077 if (na.getErrorCode() == LibFormulaErrorValue.ERROR_NA)
078 {
079 return RETURN_TRUE;
080 }
081 }
082 else
083 {
084 if (value == null)
085 {
086 return RETURN_TRUE;
087 }
088 }
089 }
090 catch (EvaluationException e)
091 {
092 if (e.getErrorValue().getErrorCode() == LibFormulaErrorValue.ERROR_NA)
093 {
094 return RETURN_TRUE;
095 }
096 }
097
098 return RETURN_FALSE;
099 }
100
101 public String getCanonicalName()
102 {
103 return "ISNA";
104 }
105
106 }