Tools [3] Date Conversion

Preface

Date Date is one of the most commonly used util classes in programming. There is no doubt that the date represents time, the creation time, update time, transaction time, and recording time of the data; it is a particularly important field and attribute. Usually in front-end display, database storage, data transmission and program conversion, there are many formats: Date, String, Long; operations are also divided into time format conversion, size (sequential) comparison.

1. Format conversion

    public static final String TIME_TEMPLATE = "yyyy-MM-dd HH:mm:ss";
	public static final String TIME_TEMPLATE2 = "yyyyMMddHHmmss";

	public static final String PERIOD_TEMPLATE = "yyyy-MM";

	public static final String DATE_TEMPLATE_Y_M_D = "yyyy-MM-dd";
	public static final String DATE_TEMPLATE_YMD = "yyyyMMdd";

	/**
	 * 代替SimpleDateFormat DATETIME_PATTERN 线程不安全方案
	 */

	protected static final FastDateFormat TIME_FORMAT = FastDateFormat.getInstance(TIME_TEMPLATE);
	protected static final FastDateFormat TIME_FORMAT2 = FastDateFormat.getInstance(TIME_TEMPLATE2);
	/**
	 * 代替SimpleDateFormat DATE_PATTERN 线程不安全方案
	 */
	protected static final FastDateFormat DATE_FORMAT = FastDateFormat.getInstance(DATE_TEMPLATE_Y_M_D);

	/**
	 * 代替SimpleDateFormat DATE_PATTERN 线程不安全方案
	 */
	protected static final FastDateFormat DATE_FORMAT2 = FastDateFormat.getInstance(DATE_TEMPLATE_YMD);

	/**
	 * 代替SimpleDateFormat PERIOD_PATTERN 线程不安全方案
	 */
	protected static final FastDateFormat PERIOD_FORMAT = FastDateFormat.getInstance(PERIOD_TEMPLATE);

• Date converted to String format time

    /**
	 * TITIL 日期转换成字符串 yyyy/MM/dd HH:mm:ss
	 * @DateTime 2017年6月23日 下午2:50:27
	 *
	 * @param date
	 * @return
	 */
	public static String convertDateToStringFormatTime(Date date) {

		if (date == null) {
			return null;
		}
		return TIME_FORMAT.format(date);
	}

	/**
	 * TITIL 日期转换成字符串 yyyymmddhhmiss
	 * @DateTime 2017年6月23日 下午2:50:27
	 *
	 * @param date
	 * @return
	 */
	public static String convertDateToStringFormatTime2(Date date) {

		if (date == null) {
			return null;
		}
		return TIME_FORMAT2.format(date);
	}

	/**
	 * TITIL 日期转换成字符串 yyyy-MM-dd
	 * @DateTime 2017年6月23日 下午2:50:27
	 *
	 * @param date
	 * @return
	 */
	public static String convertDateToString(Date date) {

		if (date == null) {
			return null;
		}
		return DATE_FORMAT.format(date);
	}

	/**
	 * TITIL 日期转换成字符串 yyyyMMdd
	 * @DateTime 2017年6月23日 下午2:50:27
	 *
	 * @param date
	 * @return
	 */
	public static String convertDateToString2(Date date) {

		if (date == null) {
			return null;
		}
		return DATE_FORMAT2.format(date);
	}

	/**
	 *  @author 
	 *	@DateTime 2018年7月16日 下午8:47:34
	 *
	 *  @param date
	 *  @return
	 */
	public static String convertDateToPeriod(Date date) {
		if (date == null) {
			return null;
		}
		return PERIOD_FORMAT.format(date);
	}

• String converted to Date format time

	/**
	 * titil : 字符串(YYYY/MM/DD)转日期
	 * @DateTime 2018年1月18日 下午3:23:00
	 * 
	 * @param strDate
	 * @return
	 * @throws ParseException
	 */
	public static Date convertStringToDate(String strDate) {

		try {
			return TIME_FORMAT.parse(strDate);
		} catch (ParseException pe) {
			throw new JobRuntimeException(pe.getMessage(), pe);
		}
	}

	public static Date convertStringToDate2(String strDate) {

		try {
			return TIME_FORMAT2.parse(strDate);
		} catch (ParseException pe) {
			throw new JobRuntimeException(pe.getMessage(), pe);
		}
	}

	/**
	 * titil : 字符串(YYYY/MM/DD)转日期
	 * @author 
	 * @DateTime 2018年1月18日 下午3:23:00
	 * 
	 * @param strDate
	 * @return
	 * @throws ParseException
	 */
	public static Date convertStringDateToDate(String strDate) {

		try {
			return DATE_FORMAT2.parse(strDate);
		} catch (ParseException pe) {
			throw new JobRuntimeException(pe.getMessage(), pe);
		}
	}

	public static Date convertStringToDateFormatYmd(String strDate) {

		try {
			return DATE_FORMAT.parse(strDate);
		} catch (ParseException pe) {
			throw new JobRuntimeException(pe.getMessage(), pe);
		}
	}

• Long converted to Date format time

	public static Date convertSecondLongToDate(Long secondLong) {
		Date date = null;
		if (secondLong == null || secondLong.longValue() == 0) {
			return date;
		}
		date = new Date(secondLong * 1000);
		return date;
	}

• Date converted to Long format time

	public static Long convertSecondLongToDate(Date date) {
		Long long = null;
		if (date == null) {
			return null;
		}
		long = date.getTime();
		return long;
	}

Two, SimpleDateFormat package

	/**
	 * 日期型转换为YYYY-MM-DD类型
	 * @DateTime 2017年8月11日 下午2:07:41
	 *
	 * @param glDate
	 * @return  
	 * @throws ParseException
	 * formatDateToDay
	 */
    public static Date convertByDate(Date glDate) throws ParseException {

		SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd");
		String s = simpleDateFormat.format(glDate);
		Date date = simpleDateFormat.parse(s);
		return date;

	}
    /**
	 * 日期型转换为YYYY-MM-DD类型
	 * @DateTime 2017年8月11日 下午2:07:41
	 *
	 * @param glDate
	 * @return  
	 * @throws ParseException
	 * formatDateToDay
	 */
	public static Date convertByDateTime(Date glDate) throws ParseException {

		SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
		String s = simpleDateFormat.format(glDate);
		Date date = simpleDateFormat.parse(s);
		return date;

	}

	/**
	 * 查询期间的最后一天
	 * @DateTime 2017年8月16日 下午2:15:53
	 *
	 * @param periodName
	 * @return 
	 * @throws ParseException
	 * getLastDayOfPeriod
	 */
	public static Date getPeriodLastDay(String periodName) throws ParseException {
		Calendar calendar = Calendar.getInstance();
		DateFormat format1 = new SimpleDateFormat("yyyy-MM");
		calendar.setTime(format1.parse(periodName));
		calendar.set(Calendar.DAY_OF_MONTH,         calendar.getActualMaximum(Calendar.DAY_OF_MONTH));
		calendar.set(Calendar.HOUR_OF_DAY, calendar.getActualMaximum(Calendar.HOUR_OF_DAY));
		calendar.set(Calendar.MINUTE, calendar.getActualMaximum(Calendar.MINUTE));
		calendar.set(Calendar.SECOND, calendar.getActualMaximum(Calendar.SECOND));
		calendar.set(Calendar.MILLISECOND, calendar.getActualMaximum(Calendar.MILLISECOND));
		return calendar.getTime();
	}

Third, the Calendar package

    /**
	 * 查询期间的最后一天
	 * @DateTime 2017年8月16日 下午2:15:53
	 *
	 * @param periodName
	 * @return 
	 * @throws ParseException
	 * getLastDayOfPeriod
	 */
	public static Date getPeriodLastDay(String periodName) throws ParseException {
		Calendar calendar = Calendar.getInstance();
		DateFormat format1 = new SimpleDateFormat("yyyy-MM");
		calendar.setTime(format1.parse(periodName));
		calendar.set(Calendar.DAY_OF_MONTH, calendar.getActualMaximum(Calendar.DAY_OF_MONTH));
		calendar.set(Calendar.HOUR_OF_DAY, calendar.getActualMaximum(Calendar.HOUR_OF_DAY));
		calendar.set(Calendar.MINUTE, calendar.getActualMaximum(Calendar.MINUTE));
		calendar.set(Calendar.SECOND, calendar.getActualMaximum(Calendar.SECOND));
		calendar.set(Calendar.MILLISECOND, calendar.getActualMaximum(Calendar.MILLISECOND));
		return calendar.getTime();
	}

	/**
	 * 查询期间的第一天
	 * @DateTime 2017年8月16日 下午2:15:53
	 *
	 * @param periodName
	 * @return
	 * @throws ParseException
	 */
	public static Date getPeriodFirstDay(String periodName) throws ParseException {
		Calendar calendar = Calendar.getInstance();
		DateFormat format1 = new SimpleDateFormat("yyyy-MM");
		calendar.setTime(format1.parse(periodName));

		return calendar.getTime();
	}

	/**获取具体时间
	 * @DateTime 2017年8月11日 下午4:47:16
	 *
	 * @param glDate
	 * @param dayNum
	 * @return
	 */
	public static Date addDayByDate(Date glDate, int dayNum) {
		Calendar cl = Calendar.getInstance();
		cl.setTime(glDate);
		cl.add(Calendar.DATE, dayNum);
		Date date = cl.getTime();
		return date;
	}

	/**获取具体时间
	 * @DateTime 2017年9月19日 下午5:12:57
	 *
	 * @param date
	 * @return
	 */
	public static Date getUpperLastDay(Date date) {
		Calendar calendar = Calendar.getInstance();
		calendar.setTime(date);
		calendar.set(Calendar.DAY_OF_MONTH, 1);
		calendar.add(Calendar.DAY_OF_MONTH, -1);
		return calendar.getTime();

	}

Fourth, time size comparison

	/**
	 * @author 
	 * @DateTime 2018年2月8日 下午8:57:16
	 *
	 * @param d1
	 * @param d2
	 * @return
	 */
	public static int compareDate(Date d1, Date d2) {

		try {
			if (d1 == null && d2 == null) {
				return 0;
			} else if (d1.getTime() > d2.getTime()) {
				return 1;
			} else if (d1.getTime() < d2.getTime()) {
				return -1;
			} else {
				return 0;
			}
		} catch (Exception exception) {
			Log.error(exception.getMessage());
			throw new RuntimeException(exception.getMessage(), exception);
		}
	}