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: IsErrorFunction.java,v 1.4 2007/04/01 13:51:52 taqua Exp $ 28: * ------------ 29: * (C) Copyright 2006-2007, by Pentaho Corporation. 30: */ 31: package org.jfree.formula.function.information; 32: 33: import org.jfree.formula.ErrorValue; 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: import org.jfree.formula.typing.coretypes.ErrorType; 42: import org.jfree.formula.typing.coretypes.LogicalType; 43: 44: /** 45: * This function returns true if the parameter is of error. 46: * 47: * @author Cedric Pronzato 48: * 49: */ 50: public class IsErrorFunction implements Function 51: { 52: private static final TypeValuePair RETURN_TRUE = new TypeValuePair(LogicalType.TYPE, Boolean.TRUE); 53: private static final TypeValuePair RETURN_FALSE = new TypeValuePair(LogicalType.TYPE, Boolean.FALSE); 54: 55: public IsErrorFunction() 56: { 57: } 58: 59: public TypeValuePair evaluate(FormulaContext context, ParameterCallback parameters) throws EvaluationException 60: { 61: if(parameters.getParameterCount() != 1) 62: { 63: throw new EvaluationException(LibFormulaErrorValue.ERROR_ARGUMENTS_VALUE); 64: } 65: 66: try 67: { 68: final Type type = parameters.getType(0); 69: Object value = parameters.getValue(0); 70: 71: if(ErrorType.TYPE.equals(type) && value instanceof ErrorValue) 72: { 73: return RETURN_TRUE; 74: } 75: } catch (EvaluationException e) 76: { 77: return RETURN_TRUE; 78: } 79: 80: return RETURN_FALSE; 81: } 82: 83: public String getCanonicalName() 84: { 85: return "ISERROR"; 86: } 87: 88: }