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: SumFunction.java 3186 2007-08-15 16:54:01Z mimil $ 028 * ------------ 029 * (C) Copyright 2006-2007, by Pentaho Corporation. 030 */ 031 package org.jfree.formula.function.math; 032 033 import org.jfree.formula.EvaluationException; 034 import org.jfree.formula.FormulaContext; 035 import org.jfree.formula.LibFormulaErrorValue; 036 import org.jfree.formula.function.Function; 037 import org.jfree.formula.function.ParameterCallback; 038 import org.jfree.formula.lvalues.TypeValuePair; 039 import org.jfree.formula.typing.Type; 040 import org.jfree.formula.typing.coretypes.NumberType; 041 import org.jfree.formula.typing.sequence.NumberSequence; 042 import org.jfree.formula.util.NumberUtil; 043 044 import java.math.BigDecimal; 045 046 /** 047 * Creation-Date: 31.10.2006, 17:39:19 048 * 049 * @author Thomas Morgner 050 */ 051 public class SumFunction implements Function 052 { 053 public static final BigDecimal ZERO = new BigDecimal(0); 054 055 public SumFunction() 056 { 057 } 058 059 public String getCanonicalName() 060 { 061 return "SUM"; 062 } 063 064 public TypeValuePair evaluate(final FormulaContext context, 065 final ParameterCallback parameters) 066 throws EvaluationException 067 { 068 BigDecimal computedResult = ZERO; 069 final int parameterCount = parameters.getParameterCount(); 070 071 if (parameterCount == 0) 072 { 073 throw new EvaluationException(LibFormulaErrorValue.ERROR_ARGUMENTS_VALUE); 074 } 075 076 for (int paramIdx = 0; paramIdx < parameterCount; paramIdx++) 077 { 078 final Type type = parameters.getType(paramIdx); 079 final Object value = parameters.getValue(paramIdx); 080 final NumberSequence sequence = context.getTypeRegistry().convertToNumberSequence(type, value); 081 082 while (sequence.hasNext()) 083 { 084 computedResult = compute(sequence.nextNumber(), computedResult); 085 } 086 } 087 088 return new TypeValuePair(NumberType.GENERIC_NUMBER, computedResult); 089 } 090 091 private BigDecimal compute(final Number value, 092 final BigDecimal computedResult) throws EvaluationException 093 { 094 if (value == null) 095 { 096 // no-op .. 097 return computedResult; 098 } 099 100 return computedResult.add(NumberUtil.getAsBigDecimal(value)); 101 } 102 }