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: FindFunction.java 3521 2007-10-16 10:55:14Z tmorgner $
028 * ------------
029 * (C) Copyright 2006-2007, by Pentaho Corporation.
030 */
031 package org.jfree.formula.function.text;
032
033 import java.math.BigDecimal;
034
035 import org.jfree.formula.EvaluationException;
036 import org.jfree.formula.FormulaContext;
037 import org.jfree.formula.LibFormulaErrorValue;
038 import org.jfree.formula.function.Function;
039 import org.jfree.formula.function.ParameterCallback;
040 import org.jfree.formula.lvalues.TypeValuePair;
041 import org.jfree.formula.typing.Type;
042 import org.jfree.formula.typing.TypeRegistry;
043 import org.jfree.formula.typing.coretypes.NumberType;
044
045 /**
046 * This function returns the starting position of a given text in the given text.
047 *
048 * @author Cedric Pronzato
049 */
050 public class FindFunction implements Function
051 {
052 public FindFunction()
053 {
054 }
055
056 public TypeValuePair evaluate(final FormulaContext context, final ParameterCallback parameters) throws EvaluationException
057 {
058 final int parameterCount = parameters.getParameterCount();
059 if (parameterCount < 2 || parameterCount > 3)
060 {
061 throw new EvaluationException(LibFormulaErrorValue.ERROR_ARGUMENTS_VALUE);
062 }
063 final TypeRegistry typeRegistry = context.getTypeRegistry();
064
065 final Type searchType = parameters.getType(0);
066 final Object searchValue = parameters.getValue(0);
067 final Type textType = parameters.getType(1);
068 final Object textValue = parameters.getValue(1);
069 Type indexType = null;
070 Object indexValue = null;
071
072 if (parameterCount == 3)
073 {
074 indexType = parameters.getType(2);
075 indexValue = parameters.getValue(2);
076 }
077
078 final String search = typeRegistry.convertToText(searchType, searchValue);
079 final String text = typeRegistry.convertToText(textType, textValue);
080
081 if (search == null || text == null)
082 {
083 throw new EvaluationException(LibFormulaErrorValue.ERROR_INVALID_ARGUMENT_VALUE);
084 }
085 int indexFrom = 0;
086
087 if (indexType != null && indexValue != null)
088 {
089 final Number n = typeRegistry.convertToNumber(indexType, indexValue);
090 if (n.intValue() >= 1)
091 {
092 indexFrom = n.intValue() - 1;
093 }
094 else
095 {
096 throw new EvaluationException(LibFormulaErrorValue.ERROR_INVALID_ARGUMENT_VALUE);
097 }
098 }
099
100 final int index = text.indexOf(search, indexFrom);
101 if (index < 0)
102 {
103 throw new EvaluationException(LibFormulaErrorValue.ERROR_NOT_FOUND_VALUE);
104 }
105
106 return new TypeValuePair(NumberType.GENERIC_NUMBER, new BigDecimal(index + 1));
107 }
108
109 public String getCanonicalName()
110 {
111 return "FIND";
112 }
113
114 }