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: IfFunction.java,v 1.7 2007/04/01 13:51:52 taqua Exp $ 28: * ------------ 29: * (C) Copyright 2006-2007, by Pentaho Corporation. 30: */ 31: package org.jfree.formula.function.logical; 32: 33: import org.jfree.formula.EvaluationException; 34: import org.jfree.formula.FormulaContext; 35: import org.jfree.formula.LibFormulaErrorValue; 36: import org.jfree.formula.function.Function; 37: import org.jfree.formula.function.ParameterCallback; 38: import org.jfree.formula.lvalues.TypeValuePair; 39: import org.jfree.formula.typing.Type; 40: import org.jfree.formula.typing.coretypes.LogicalType; 41: 42: /** 43: * Creation-Date: 04.11.2006, 18:28:15 44: * 45: * @author Thomas Morgner 46: */ 47: public class IfFunction implements Function 48: { 49: private static final TypeValuePair RETURN_FALSE = new TypeValuePair(LogicalType.TYPE, Boolean.FALSE); 50: 51: public IfFunction() 52: { 53: } 54: 55: public String getCanonicalName() 56: { 57: return "IF"; 58: } 59: 60: public TypeValuePair evaluate(FormulaContext context, 61: ParameterCallback parameters) 62: throws EvaluationException 63: { 64: final int parameterCount = parameters.getParameterCount(); 65: if (parameterCount < 2) 66: { 67: throw new EvaluationException(LibFormulaErrorValue.ERROR_ARGUMENTS_VALUE); 68: } 69: 70: final Type conditionType = parameters.getType(0); 71: final Object conditionValue = parameters.getValue(0); 72: final Boolean condition = context.getTypeRegistry().convertToLogical(conditionType, conditionValue); 73: if(condition == null) 74: { 75: throw new EvaluationException(LibFormulaErrorValue.ERROR_INVALID_ARGUMENT_VALUE); 76: } 77: if (Boolean.TRUE.equals(condition)) 78: { 79: final Object value = parameters.getValue(1); 80: final Type type = parameters.getType(1); 81: return new TypeValuePair(type, value); 82: } 83: // if condition is false and no third parameter, return false 84: if(parameterCount == 2 || parameters.getValue(2) == null) 85: { 86: return RETURN_FALSE; 87: } 88: // else return third parameter 89: final Object value = parameters.getValue(2); 90: final Type type = parameters.getType(2); 91: return new TypeValuePair(type, value); 92: } 93: }