Frames | No Frames |
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: ChooseFunction.java 2752 2007-04-10 14:10:41Z taqua $ 28: * ------------ 29: * (C) Copyright 2006-2007, by Pentaho Corporation. 30: */ 31: 32: package org.jfree.formula.function.information; 33: 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: 42: /** 43: * This function uses an index to return a value from a list of values. 44: * The first value index is 1, 2 for the second and so on. 45: * 46: * @author Cedric Pronzato 47: */ 48: public class ChooseFunction implements Function 49: { 50: public ChooseFunction() 51: { 52: } 53: 54: public String getCanonicalName() 55: { 56: return "CHOOSE"; 57: } 58: 59: public TypeValuePair evaluate(final FormulaContext context, 60: final ParameterCallback parameters) 61: throws EvaluationException 62: { 63: 64: if(parameters.getParameterCount() <= 2) 65: { 66: throw new EvaluationException(LibFormulaErrorValue.ERROR_ARGUMENTS_VALUE); 67: } 68: 69: final Type indexType = parameters.getType(0); 70: final Object indexValue = parameters.getValue(0); 71: 72: final int index= context.getTypeRegistry().convertToNumber(indexType, indexValue).intValue(); 73: if(index >= 1 && index < parameters.getParameterCount()) 74: { 75: return new TypeValuePair(parameters.getType(index), parameters.getValue(index)); 76: } 77: // else 78: throw new EvaluationException(LibFormulaErrorValue.ERROR_INVALID_ARGUMENT_VALUE); 79: } 80: }