| /* ==================================================================== |
| Licensed to the Apache Software Foundation (ASF) under one or more |
| contributor license agreements. See the NOTICE file distributed with |
| this work for additional information regarding copyright ownership. |
| The ASF licenses this file to You under the Apache License, Version 2.0 |
| (the "License"); you may not use this file except in compliance with |
| the License. You may obtain a copy of the License at |
| |
| http://www.apache.org/licenses/LICENSE-2.0 |
| |
| Unless required by applicable law or agreed to in writing, software |
| distributed under the License is distributed on an "AS IS" BASIS, |
| WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| See the License for the specific language governing permissions and |
| limitations under the License. |
| ==================================================================== */ |
| |
| package org.apache.poi.ss.formula.functions; |
| |
| import java.util.Calendar; |
| import java.util.Date; |
| |
| import org.apache.poi.ss.formula.OperationEvaluationContext; |
| import org.apache.poi.ss.formula.eval.ErrorEval; |
| import org.apache.poi.ss.formula.eval.EvaluationException; |
| import org.apache.poi.ss.formula.eval.NumberEval; |
| import org.apache.poi.ss.formula.eval.ValueEval; |
| import org.apache.poi.ss.usermodel.DateUtil; |
| import org.apache.poi.util.LocaleUtil; |
| |
| /** |
| * Implementation for the Excel EOMONTH() function.<p> |
| * <p> |
| * EOMONTH() returns the date of the last day of a month..<p> |
| * <p> |
| * <b>Syntax</b>:<br> |
| * <b>EOMONTH</b>(<b>start_date</b>,<b>months</b>)<p> |
| * <p> |
| * <b>start_date</b> is the starting date of the calculation |
| * <b>months</b> is the number of months to be added to <b>start_date</b>, |
| * to give a new date. For this new date, <b>EOMONTH</b> returns the date of |
| * the last day of the month. <b>months</b> may be positive (in the future), |
| * zero or negative (in the past). |
| */ |
| public class EOMonth implements FreeRefFunction { |
| public static final FreeRefFunction instance = new EOMonth(); |
| |
| @Override |
| public ValueEval evaluate(ValueEval[] args, OperationEvaluationContext ec) { |
| if (args.length != 2) { |
| return ErrorEval.VALUE_INVALID; |
| } |
| |
| try { |
| double startDateAsNumber = NumericFunction.singleOperandEvaluate(args[0], ec.getRowIndex(), ec.getColumnIndex()); |
| int months = (int) NumericFunction.singleOperandEvaluate(args[1], ec.getRowIndex(), ec.getColumnIndex()); |
| |
| // Excel treats date 0 as 1900-01-00; EOMONTH results in 1900-01-31 |
| if (startDateAsNumber >= 0.0 && startDateAsNumber < 1.0) { |
| startDateAsNumber = 1.0; |
| } |
| |
| Date startDate = DateUtil.getJavaDate(startDateAsNumber, false); |
| |
| Calendar cal = LocaleUtil.getLocaleCalendar(); |
| cal.setTime(startDate); |
| cal.clear(Calendar.HOUR); |
| cal.set(Calendar.HOUR_OF_DAY, 0); |
| cal.clear(Calendar.MINUTE); |
| cal.clear(Calendar.SECOND); |
| cal.clear(Calendar.MILLISECOND); |
| |
| cal.add(Calendar.MONTH, months + 1); |
| cal.set(Calendar.DAY_OF_MONTH, 1); |
| cal.add(Calendar.DAY_OF_MONTH, -1); |
| |
| return new NumberEval(DateUtil.getExcelDate(cal.getTime())); |
| } catch (EvaluationException e) { |
| return e.getErrorEval(); |
| } |
| } |
| } |