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: MinusSignOperator.java 2887 2007-06-06 17:07:52Z taqua $ 028 * ------------ 029 * (C) Copyright 2006-2007, by Pentaho Corporation. 030 */ 031 package org.jfree.formula.operators; 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.lvalues.TypeValuePair; 039 import org.jfree.formula.typing.Type; 040 import org.jfree.formula.typing.TypeRegistry; 041 042 /** 043 * Creation-Date: 02.11.2006, 10:27:03 044 * 045 * @author Thomas Morgner 046 */ 047 public class MinusSignOperator implements PrefixOperator 048 { 049 private static final BigDecimal ZERO = new BigDecimal(0); 050 051 052 public MinusSignOperator() 053 { 054 } 055 056 public TypeValuePair evaluate(final FormulaContext context, 057 final TypeValuePair value1) 058 throws EvaluationException 059 { 060 final Type type = value1.getType(); 061 final Object val = value1.getValue(); 062 if (val == null) 063 { 064 throw new EvaluationException(LibFormulaErrorValue.ERROR_NA_VALUE); 065 } 066 067 if (type.isFlagSet(Type.NUMERIC_TYPE)) 068 { 069 final TypeRegistry typeRegistry = context.getTypeRegistry(); 070 // return the same as zero minus value. 071 final Number number = typeRegistry.convertToNumber(type, val); 072 final BigDecimal value = getAsBigDecimal(number); 073 return new TypeValuePair(type, ZERO.subtract(value)); 074 } 075 076 if(val instanceof Number) 077 { 078 final BigDecimal value = getAsBigDecimal((Number)val); 079 return new TypeValuePair(type, ZERO.subtract(value)); 080 } 081 082 throw new EvaluationException 083 (LibFormulaErrorValue.ERROR_INVALID_ARGUMENT_VALUE); 084 } 085 086 private BigDecimal getAsBigDecimal(final Number number) 087 { 088 if (number instanceof BigDecimal) 089 { 090 return (BigDecimal) number; 091 } 092 return new BigDecimal(number.toString()); 093 } 094 095 public String toString() 096 { 097 return "-"; 098 } 099 }