Java tutorial
/** * This file is part of mycollab-core. * * mycollab-core 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 3 of the License, or * (at your option) any later version. * * mycollab-core 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 mycollab-core. If not, see <http://www.gnu.org/licenses/>. */ package com.esofthead.mycollab.core.utils; import java.text.DateFormat; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.Date; import java.util.GregorianCalendar; import java.util.HashMap; import java.util.Locale; import java.util.Map; import java.util.TimeZone; import org.apache.commons.lang3.StringUtils; import org.joda.time.DateTime; import org.joda.time.DateTimeZone; import org.ocpsoft.prettytime.PrettyTime; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.esofthead.mycollab.core.MyCollabException; /** * Utility class to process date instance * * @author MyCollab Ltd. * @since 1.0 */ public class DateTimeUtils { private static final Logger LOG = LoggerFactory.getLogger(DateTimeUtils.class); private static DateTimeZone utcZone = DateTimeZone.UTC; private static Map<String, SimpleDateFormat> dateFormats = new HashMap<String, SimpleDateFormat>(); /** * Trim hour-minute-second of date instance value to zero. * * @param value * @return */ public static Date trimHMSOfDate(Date value) { DateFormat df = new SimpleDateFormat("yyyy-MM-dd"); try { return df.parse(df.format(value.getTime())); } catch (ParseException e) { throw new MyCollabException(e); } } public static Date getCurrentDateWithoutMS() { GregorianCalendar calendar = new GregorianCalendar(); calendar.set(Calendar.SECOND, 0); calendar.set(Calendar.MINUTE, 0); return calendar.getTime(); } public static Date convertDateByString(String strDate, String format) { if (!StringUtils.isEmpty(strDate)) { try { SimpleDateFormat formatter = new SimpleDateFormat(format); return formatter.parse(strDate); } catch (ParseException e) { LOG.error("Error while parse date", e); } } return new Date(); } public static String converToStringWithUserTimeZone(String dateVal, String dateFormat, TimeZone userTimeZone) { Date date = convertDateByFormatW3C(dateVal); return converToStringWithUserTimeZone(date, dateFormat, userTimeZone); } /** * * @param strDate * @return */ public static Date convertDateByFormatW3C(String strDate) { String formatW3C = "yyyy-MM-dd'T'HH:mm:ss"; if (strDate != null && !strDate.equals("")) { SimpleDateFormat formatter = new SimpleDateFormat(formatW3C); try { return formatter.parse(strDate); } catch (ParseException e) { LOG.error("Error while parse date", e); } } return null; } public static String converToStringWithUserTimeZone(Date date, String dateFormat, TimeZone userTimeZone) { if (date == null) return ""; return formatDate(date, dateFormat, userTimeZone); } public static String getPrettyDateValue(Date dateTime, Locale locale) { if (dateTime == null) { return ""; } PrettyTime p = new PrettyTime(locale); return p.format(dateTime); } /** * * @param date * @param duration * Example: Date date = subtractOrAddDayDuration(new Date(), -2); * // Result: the last 2 days * * Date date = subtractOrAddDayDuration(new Date(), 2); // * Result: the next 2 days * @return */ public static Date subtractOrAddDayDuration(Date date, int duration) { Calendar cal = new GregorianCalendar(); cal.setTime(date); cal.add(Calendar.DAY_OF_MONTH, duration); Date dateExpect = cal.getTime(); return dateExpect; } public static String formatDate(Date date, String dateFormat) { return formatDate(date, dateFormat, null); } public static String formatDate(Date date, String dateFormat, TimeZone timezone) { if (date == null) { return ""; } SimpleDateFormat simpleDateFormat = getDateFormat(dateFormat); if (timezone != null) { simpleDateFormat.setTimeZone(timezone); } return simpleDateFormat.format(date); } private static SimpleDateFormat getDateFormat(String format) { SimpleDateFormat dateFormat = dateFormats.get(format); if (dateFormat != null) { return dateFormat; } else { dateFormat = new SimpleDateFormat(format); dateFormats.put(format, dateFormat); return dateFormat; } } public static Date convertTimeFromSystemTimezoneToUTC(long timeInMillis) { DateTime dt = new DateTime(); dt = dt.withMillis(-DateTimeZone.getDefault().getOffset(timeInMillis) + timeInMillis); dt = dt.withZone(utcZone); Date date = dt.toDate(); return date; } /** * Convert from UTC time to default time zone of system * * @param timeInMillis * @return */ public static Date convertTimeFromUTCToSystemTimezone(long timeInMillis) { DateTime dt = new DateTime(); dt = dt.withMillis(DateTimeZone.getDefault().getOffset(timeInMillis) + timeInMillis); dt = dt.withZone(utcZone); Date date = dt.toDate(); return date; } /** * * @param date * @return array of two date elements, first is the first day of week, and * the second is the end week date */ public static Date[] getBounceDateofWeek(Date date) { Calendar calendar = new GregorianCalendar(); calendar.setFirstDayOfWeek(Calendar.MONDAY); calendar.setTime(date); calendar.set(Calendar.DAY_OF_WEEK, Calendar.MONDAY); Date begin = calendar.getTime(); calendar.set(Calendar.DAY_OF_WEEK, Calendar.SUNDAY); Date end = calendar.getTime(); return new Date[] { begin, end }; } public static int compareByDate(Date date1, Date date2) { Date newDate1 = trimHMSOfDate(date1); Date newDate2 = trimHMSOfDate(date2); return newDate1.compareTo(newDate2); } }