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: NumberUtil.java 3522 2007-10-16 10:56:57Z tmorgner $ 028 * ------------ 029 * (C) Copyright 2006-2007, by Pentaho Corporation. 030 */ 031 032 package org.jfree.formula.util; 033 034 import java.math.BigDecimal; 035 036 import org.jfree.formula.EvaluationException; 037 import org.jfree.formula.LibFormulaErrorValue; 038 039 public class NumberUtil 040 { 041 public static final BigDecimal DELTA = new BigDecimal("0.000000000000000000000000000005"); 042 043 private NumberUtil() 044 { 045 } 046 047 public static BigDecimal getAsBigDecimal(final Number number) throws EvaluationException 048 { 049 if (number == null) 050 { 051 throw new EvaluationException( 052 LibFormulaErrorValue.ERROR_INVALID_ARGUMENT_VALUE); 053 } 054 055 if(number instanceof BigDecimal) 056 { 057 return (BigDecimal)number; 058 } 059 else 060 { 061 return new BigDecimal(number.toString()); 062 } 063 } 064 065 public static Integer performIntRounding(BigDecimal n) 066 { 067 068 try 069 { 070 // no need to go further if the value is already an integer 071 n = n.setScale(0); 072 return new Integer(n.intValue()); 073 } 074 catch(ArithmeticException e) 075 { 076 //ignore and continue 077 } 078 079 final BigDecimal round; 080 if(n.signum()<0) 081 { 082 n = n.subtract(DELTA); 083 round = n.setScale(0, BigDecimal.ROUND_UP); 084 } 085 else 086 { 087 n = n.add(DELTA); 088 round = n.setScale(1, BigDecimal.ROUND_DOWN); 089 } 090 return new Integer(round.intValue()); 091 } 092 093 public static BigDecimal removeTrailingZeros(BigDecimal bd) 094 { 095 if(bd.signum() == 0) 096 { 097 return bd.setScale(0); 098 } 099 100 // Todo: This approach is very expensive. There must be a better way ... 101 try 102 { 103 while(true) 104 { 105 final int scale = bd.scale(); 106 if (scale == 0) 107 { 108 return bd; 109 } 110 bd = bd.setScale(scale-1); 111 } 112 } 113 catch(ArithmeticException ae) 114 { 115 return bd; 116 } 117 } 118 }