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: URLEncodeFunction.java 3521 2007-10-16 10:55:14Z tmorgner $
028     * ------------
029     * (C) Copyright 2006-2007, by Pentaho Corporation.
030     */
031    
032    package org.jfree.formula.function.text;
033    
034    import java.io.UnsupportedEncodingException;
035    
036    import org.jfree.formula.EvaluationException;
037    import org.jfree.formula.FormulaContext;
038    import org.jfree.formula.LibFormulaErrorValue;
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.Type;
043    import org.jfree.formula.typing.coretypes.TextType;
044    import org.jfree.formula.util.URLEncoder;
045    
046    /**
047     * This function encodes a given text using the URL-Encoding schema. An optional
048     * second parameter can be given to specify the character encoding that should
049     * be used when converting text to bytes.
050     *
051     * @author Cedric Pronzato
052     */
053    public class URLEncodeFunction implements Function
054    {
055      public URLEncodeFunction()
056      {
057      }
058    
059      public TypeValuePair evaluate(final FormulaContext context, final ParameterCallback parameters) throws EvaluationException
060      {
061        final int parameterCount = parameters.getParameterCount();
062        if (parameterCount < 1)
063        {
064          throw new EvaluationException(LibFormulaErrorValue.ERROR_ARGUMENTS_VALUE);
065        }
066        final Type textType = parameters.getType(0);
067        final Object textValue = parameters.getValue(0);
068        final String textResult =
069            context.getTypeRegistry().convertToText(textType, textValue);
070    
071        if(textResult == null)
072        {
073          throw new EvaluationException(LibFormulaErrorValue.ERROR_INVALID_ARGUMENT_VALUE);
074        }
075    
076        String encodingResult = null;
077        if(parameterCount == 2)
078        {
079          final Type encodingType = parameters.getType(1);
080          final Object encodingValue = parameters.getValue(1);
081          encodingResult = context.getTypeRegistry().convertToText(encodingType, encodingValue);
082          if(encodingResult == null)
083          {
084            throw new EvaluationException(LibFormulaErrorValue.ERROR_INVALID_ARGUMENT_VALUE);
085          }
086        }
087        try
088        {
089          if (encodingResult == null)
090          {
091            return new TypeValuePair
092                (TextType.TYPE, URLEncoder.encode(textResult, "ISO-8859-1"));
093          }
094          return new TypeValuePair
095              (TextType.TYPE, URLEncoder.encode(textResult, encodingResult));
096    
097        }
098        catch(UnsupportedEncodingException use)
099        {
100          throw new EvaluationException(LibFormulaErrorValue.ERROR_INVALID_ARGUMENT_VALUE);
101        }
102      }
103    
104      public String getCanonicalName()
105      {
106        return "URLENCODE";
107      }
108    
109    }