Java tutorial
/* * ==================================================================== * Copyright (C) 1997-2008 by Naijatek.com * * All copyright notices regarding MyAlumni MUST remain * intact in the scripts and in the outputted HTML. * The "powered by" text/logo with a link back to * http://www.naijatek.com in * the footer of the pages MUST remain visible when the pages * are viewed on the internet or intranet. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * * Support can be obtained from support forums at: * http://www.naijatek.com/myalumni/forum * * Correspondence and Marketing Questions can be sent to: * info at naijatek com * * <p>Title: MyAlumni </p> * <p>Description: This system helps keep alive the line of communications between alumni/alumnus</p> * <p>Copyright: Copyright (c) 1997-2008</p> * <p>Company: Naijatek Solutions (http://www.naijatek.com)</p> * @author Folashade Adeyosoye (shardayyy@naijatek.com) * @version 1.0 */ package net.naijatek.myalumni.util.date; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.Date; import java.util.GregorianCalendar; import java.util.Locale; import java.util.MissingResourceException; import java.util.ResourceBundle; import net.naijatek.myalumni.util.BaseConstants; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.context.i18n.LocaleContextHolder; /** * Date Converter Utility Class * This is used to convert Strings to Dates and Timestamps * */ public class DateConverterUtil { //~ Static fields/initializers ============================================= private static Log log = LogFactory.getLog(DateConverterUtil.class); private static String defaultDatePattern = null; private static String timePattern = "HH:mm"; //~ Methods ================================================================ /** * Return default datePattern (MM/dd/yyyy) * @return a string representing the date pattern on the UI */ public static synchronized String getDatePattern() { Locale locale = LocaleContextHolder.getLocale(); try { defaultDatePattern = ResourceBundle.getBundle("", locale).getString("date.format"); } catch (MissingResourceException mse) { //defaultDatePattern = "MM-dd-yyyy"; defaultDatePattern = "yyyy-MM-dd"; } log.info("### Default Date Pattern = " + defaultDatePattern); return defaultDatePattern; } public static String getDateTimePattern() { //return DateConverterUtil.getDatePattern() + " HH:mm:ss.S"; return DateConverterUtil.getDatePattern(); } /** * This method attempts to convert an Oracle-formatted date * in the form dd-MMM-yyyy to mm/dd/yyyy. * * @param aDate date from database as a string * @return formatted string for the ui */ public static final String getDate(Date aDate) { SimpleDateFormat df = null; String returnValue = ""; if (aDate != null) { df = new SimpleDateFormat(getDatePattern()); returnValue = df.format(aDate); } return (returnValue); } /** * This method generates a string representation of a date/time * in the format you specify on input * * @param aMask the date pattern the string is in * @param strDate a string representation of a date * @return a converted Date object * @see java.text.SimpleDateFormat * @throws ParseException */ public static final Date convertStringToDate(String aMask, String strDate) throws ParseException { SimpleDateFormat df = null; Date date = null; df = new SimpleDateFormat(aMask); if (log.isDebugEnabled()) { log.debug("converting '" + strDate + "' to date with mask '" + aMask + "'"); } try { date = df.parse(strDate); } catch (ParseException pe) { //log.error("ParseException: " + pe); throw new ParseException(pe.getMessage(), pe.getErrorOffset()); } return (date); } /** * This method returns the current date time in the format: * MM/dd/yyyy HH:MM a * * @param theTime the current time * @return the current date/time */ public static String getTimeNow(Date theTime) { return getDateTime(timePattern, theTime); } /** * This method returns the current date in the format: MM/dd/yyyy * * @return the current date * @throws ParseException */ public static Calendar getToday() throws ParseException { Date today = new Date(); SimpleDateFormat df = new SimpleDateFormat(getDatePattern()); // This seems like quite a hack (date -> string -> date), // but it works ;-) String todayAsString = df.format(today); Calendar cal = new GregorianCalendar(); cal.setTime(convertStringToDate(todayAsString)); return cal; } /** * This method generates a string representation of a date's date/time * in the format you specify on input * * @param aMask the date pattern the string is in * @param aDate a date object * @return a formatted string representation of the date * * @see java.text.SimpleDateFormat */ public static final String getDateTime(String aMask, Date aDate) { SimpleDateFormat df = null; String returnValue = ""; if (aDate == null) { log.error("aDate is null!"); } else { df = new SimpleDateFormat(aMask); returnValue = df.format(aDate); } return (returnValue); } /** * This method generates a string representation of a date based * on the System Property 'dateFormat' * in the format you specify on input * * @param aDate A date to convert * @return a string representation of the date */ public static final String convertDateToString(Date aDate) { return getDateTime(getDatePattern(), aDate); } /** * This method converts a String to a date using the datePattern * * @param strDate the date to convert (in format MM/dd/yyyy) * @return a date object * * @throws ParseException */ public static Date convertStringToDate(String strDate) throws ParseException { Date aDate = null; try { if (log.isDebugEnabled()) { log.debug("converting date with pattern: " + getDatePattern()); } aDate = convertStringToDate(getDatePattern(), strDate); } catch (ParseException pe) { log.error("Could not convert '" + strDate + "' to a date, throwing exception"); pe.printStackTrace(); throw new ParseException(pe.getMessage(), pe.getErrorOffset()); } return aDate; } }