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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: DivideOperator.java,v 1.12 2007/06/06 17:07:52 taqua Exp $ 28: * ------------ 29: * (C) Copyright 2006-2007, by Pentaho Corporation. 30: */ 31: package org.jfree.formula.operators; 32: 33: import java.math.BigDecimal; 34: 35: import org.jfree.formula.EvaluationException; 36: import org.jfree.formula.LibFormulaErrorValue; 37: import org.jfree.formula.util.NumberUtil; 38: import org.jfree.util.Log; 39: 40: /** 41: * A division operation. This operation expects two valid numbers. 42: * 43: * 44: * @author Thomas Morgner 45: */ 46: public class DivideOperator extends AbstractNumericOperator 47: { 48: public DivideOperator() 49: { 50: } 51: 52: public Number evaluate(final Number number1, final Number number2) throws EvaluationException 53: { 54: final BigDecimal bd1 = new BigDecimal(number1.toString()); 55: final BigDecimal bd2 = new BigDecimal(number2.toString()); 56: if (bd2.signum() == 0) 57: { 58: // prevent a division by zero .. 59: Log.debug ("Preventing a Division by Zero: " + number2); 60: throw new EvaluationException(LibFormulaErrorValue.ERROR_ARITHMETIC_VALUE); 61: } 62: final BigDecimal divide = bd1.divide(bd2, 40, BigDecimal.ROUND_HALF_UP); 63: return NumberUtil.removeTrailingZeros(divide); 64: } 65: 66: public int getLevel() 67: { 68: return 100; 69: } 70: 71: 72: public String toString() 73: { 74: return "/"; 75: } 76: 77: public boolean isLeftOperation() 78: { 79: return true; 80: } 81: 82: /** 83: * Defines, whether the operation is associative. For associative operations, 84: * the evaluation order does not matter, if the operation appears more than 85: * once in an expression, and therefore we can optimize them a lot better than 86: * non-associative operations (ie. merge constant parts and precompute them 87: * once). 88: * 89: * @return true, if the operation is associative, false otherwise 90: */ 91: public boolean isAssociative() 92: { 93: return false; 94: } 95: 96: }