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: DivideOperator.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.LibFormulaErrorValue; 037 import org.jfree.formula.util.NumberUtil; 038 import org.jfree.util.Log; 039 040 /** 041 * A division operation. This operation expects two valid numbers. 042 * 043 * 044 * @author Thomas Morgner 045 */ 046 public class DivideOperator extends AbstractNumericOperator 047 { 048 public DivideOperator() 049 { 050 } 051 052 public Number evaluate(final Number number1, final Number number2) throws EvaluationException 053 { 054 final BigDecimal bd1 = new BigDecimal(number1.toString()); 055 final BigDecimal bd2 = new BigDecimal(number2.toString()); 056 if (bd2.signum() == 0) 057 { 058 // prevent a division by zero .. 059 Log.debug ("Preventing a Division by Zero: " + number2); 060 throw new EvaluationException(LibFormulaErrorValue.ERROR_ARITHMETIC_VALUE); 061 } 062 final BigDecimal divide = bd1.divide(bd2, 40, BigDecimal.ROUND_HALF_UP); 063 return NumberUtil.removeTrailingZeros(divide); 064 } 065 066 public int getLevel() 067 { 068 return 100; 069 } 070 071 072 public String toString() 073 { 074 return "/"; 075 } 076 077 public boolean isLeftOperation() 078 { 079 return true; 080 } 081 082 /** 083 * Defines, whether the operation is associative. For associative operations, 084 * the evaluation order does not matter, if the operation appears more than 085 * once in an expression, and therefore we can optimize them a lot better than 086 * non-associative operations (ie. merge constant parts and precompute them 087 * once). 088 * 089 * @return true, if the operation is associative, false otherwise 090 */ 091 public boolean isAssociative() 092 { 093 return false; 094 } 095 096 }