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: TimeFunction.java 3522 2007-10-16 10:56:57Z tmorgner $
028     * ------------
029     * (C) Copyright 2006-2007, by Pentaho Corporation.
030     */
031    package org.jfree.formula.function.datetime;
032    
033    import java.sql.Time;
034    
035    import org.jfree.formula.EvaluationException;
036    import org.jfree.formula.FormulaContext;
037    import org.jfree.formula.LibFormulaErrorValue;
038    import org.jfree.formula.LocalizationContext;
039    import org.jfree.formula.function.Function;
040    import org.jfree.formula.function.ParameterCallback;
041    import org.jfree.formula.lvalues.TypeValuePair;
042    import org.jfree.formula.typing.TypeRegistry;
043    import org.jfree.formula.typing.coretypes.DateTimeType;
044    import org.jfree.formula.util.DateUtil;
045    
046    /**
047     * This fonction constructs a time from hours, minutes, and seconds.
048     * 
049     * @author Cedric Pronzato
050     */
051    public class TimeFunction implements Function
052    {
053      public TimeFunction()
054      {
055      }
056    
057      public String getCanonicalName()
058      {
059        return "TIME";
060      }
061    
062      public TypeValuePair evaluate(final FormulaContext context,
063          final ParameterCallback parameters) throws EvaluationException
064      {
065        if (parameters.getParameterCount() != 3)
066        {
067          throw new EvaluationException(LibFormulaErrorValue.ERROR_ARGUMENTS_VALUE);
068        }
069        final Number n1;
070        final Number n2;
071        final Number n3;
072        try
073        {
074          final TypeRegistry typeRegistry = context.getTypeRegistry();
075          n1 = typeRegistry.convertToNumber(parameters.getType(0), parameters
076              .getValue(0));
077          n2 = typeRegistry.convertToNumber(parameters.getType(1), parameters
078              .getValue(1));
079          n3 = typeRegistry.convertToNumber(parameters.getType(2), parameters
080              .getValue(2));
081        } catch (NumberFormatException e)
082        {
083          throw new EvaluationException(
084              LibFormulaErrorValue.ERROR_INVALID_ARGUMENT_VALUE);
085        }
086    
087        if (n1 == null || n2 == null || n3 == null)
088        {
089          throw new EvaluationException(
090              LibFormulaErrorValue.ERROR_INVALID_ARGUMENT_VALUE);
091        }
092        final int hours = n1.intValue();
093        final int minutes = n2.intValue();
094        final int seconds = n3.intValue();
095    
096        final LocalizationContext localizationContext = context
097            .getLocalizationContext();
098        final Time time = DateUtil.createTime(hours, minutes, seconds,
099            localizationContext);
100    
101        return new TypeValuePair(DateTimeType.TIME_TYPE, time);
102      }
103    }