timeutil.java

mysql的jdbc驱动

		tempMap.put("WGT", new String[] { "America/Godthab" });
		tempMap.put("WMT", new String[] { "Europe/Vilnius", "Europe/Warsaw" });
		tempMap.put("WST", new String[] { "Antarctica/Casey", "Pacific/Apia",
				"Australia/Perth" });
		tempMap.put("YAKMT", new String[] { "Asia/Yakutsk" });
		tempMap.put("YAKST", new String[] { "Asia/Yakutsk" });
		tempMap.put("YAKT", new String[] { "Asia/Yakutsk" });
		tempMap.put("YAPT", new String[] { "Pacific/Yap" });
		tempMap.put("YDDT", new String[] { "America/Whitehorse",
				"America/Dawson" });
		tempMap.put("YDT", new String[] { "America/Yakutat",
				"America/Whitehorse", "America/Dawson" });
		tempMap.put("YEKMT", new String[] { "Asia/Yekaterinburg" });
		tempMap.put("YEKST", new String[] { "Asia/Yekaterinburg" });
		tempMap.put("YEKT", new String[] { "Asia/Yekaterinburg" });
		tempMap.put("YERST", new String[] { "Asia/Yerevan" });
		tempMap.put("YERT", new String[] { "Asia/Yerevan" });
		tempMap.put("YST", new String[] { "America/Yakutat",
				"America/Whitehorse", "America/Dawson" });
		tempMap.put("YWT", new String[] { "America/Yakutat" });

		ABBREVIATED_TIMEZONES = Collections.unmodifiableMap(tempMap);
	}

	/**
	 * Change the given times from one timezone to another
	 * 
	 * @param conn
	 *            the current connection to the MySQL server
	 * @param t
	 *            the times to change
	 * @param fromTz
	 *            the timezone to change from
	 * @param toTz
	 *            the timezone to change to
	 * 
	 * @return the times changed to the timezone 'toTz'
	 */
	public static Time changeTimezone(Connection conn, Time t, TimeZone fromTz,
			TimeZone toTz, boolean rollForward) {
		if ((conn != null) && conn.getUseTimezone()) {
			// Convert the timestamp from GMT to the server's timezone
			Calendar fromCal = Calendar.getInstance(fromTz);
			fromCal.setTime(t);

			int fromOffset = fromCal.get(Calendar.ZONE_OFFSET)
					+ fromCal.get(Calendar.DST_OFFSET);
			Calendar toCal = Calendar.getInstance(toTz);
			toCal.setTime(t);

			int toOffset = toCal.get(Calendar.ZONE_OFFSET)
					+ toCal.get(Calendar.DST_OFFSET);
			int offsetDiff = fromOffset - toOffset;
			long toTime = toCal.getTime().getTime();

			if (rollForward || (conn.isServerTzUTC() && !conn.isClientTzUTC())) {
				toTime += offsetDiff;
			} else {
				toTime -= offsetDiff;
			}

			Time changedTime = new Time(toTime);

			return changedTime;
		}

		return t;
	}

	/**
	 * Change the given timestamp from one timezone to another
	 * 
	 * @param conn
	 *            the current connection to the MySQL server
	 * @param tstamp
	 *            the timestamp to change
	 * @param fromTz
	 *            the timezone to change from
	 * @param toTz
	 *            the timezone to change to
	 * 
	 * @return the timestamp changed to the timezone 'toTz'
	 */
	public static Timestamp changeTimezone(Connection conn, Timestamp tstamp,
			TimeZone fromTz, TimeZone toTz, boolean rollForward) {
		if ((conn != null) && conn.getUseTimezone()) {
			// Convert the timestamp from GMT to the server's timezone
			Calendar fromCal = Calendar.getInstance(fromTz);
			fromCal.setTime(tstamp);

			int fromOffset = fromCal.get(Calendar.ZONE_OFFSET)
					+ fromCal.get(Calendar.DST_OFFSET);
			Calendar toCal = Calendar.getInstance(toTz);
			toCal.setTime(tstamp);

			int toOffset = toCal.get(Calendar.ZONE_OFFSET)
					+ toCal.get(Calendar.DST_OFFSET);
			int offsetDiff = fromOffset - toOffset;
			long toTime = toCal.getTime().getTime();

			if (rollForward || (conn.isServerTzUTC() && !conn.isClientTzUTC())) {
				toTime += offsetDiff;
			} else {
				toTime -= offsetDiff;
			}

			Timestamp changedTimestamp = new Timestamp(toTime);

			return changedTimestamp;
		}

		return tstamp;
	}

	//
	// WARN! You must externally synchronize these calendar instances
	// See ResultSet.fastDateCreate() for an example
	//
	final static Date fastDateCreate(Calendar cal, int year, int month, int day) {
		cal.clear();

		// why-oh-why is this different than java.util.date,
		// in the year part, but it still keeps the silly '0'
		// for the start month????
		cal.set(year, month - 1, day, 0, 0, 0);

		long dateAsMillis = 0;

		try {
			dateAsMillis = cal.getTimeInMillis();
		} catch (IllegalAccessError iae) {
			// Must be on JDK-1.3.1 or older....
			dateAsMillis = cal.getTime().getTime();
		}

		return new Date(dateAsMillis);
	}

	final static Time fastTimeCreate(Calendar cal, int hour, int minute,
			int second) {
		cal.clear();

		// Set 'date' to epoch of Jan 1, 1970
		cal.set(1970, 0, 1, hour, minute, second);

		long timeAsMillis = 0;

		try {
			timeAsMillis = cal.getTimeInMillis();
		} catch (IllegalAccessError iae) {
			// Must be on JDK-1.3.1 or older....
			timeAsMillis = cal.getTime().getTime();
		}

		return new Time(timeAsMillis);
	}

	final static Timestamp fastTimestampCreate(Calendar cal, int year,
			int month, int day, int hour, int minute, int seconds,
			int secondsPart) {
		cal.clear();

		// why-oh-why is this different than java.util.date,
		// in the year part, but it still keeps the silly '0'
		// for the start month????
		cal.set(year, month - 1, day, hour, minute, seconds);

		long tsAsMillis = 0;

		try {
			tsAsMillis = cal.getTimeInMillis();
		} catch (IllegalAccessError iae) {
			// Must be on JDK-1.3.1 or older....
			tsAsMillis = cal.getTime().getTime();
		}

		Timestamp ts = new Timestamp(tsAsMillis);
		ts.setNanos(secondsPart);

		return ts;
	}

	/**
	 * Returns the 'official' Java timezone name for the given timezone
	 * 
	 * @param timezoneStr
	 *            the 'common' timezone name
	 * 
	 * @return the Java timezone name for the given timezone
	 * 
	 * @throws IllegalArgumentException
	 *             DOCUMENT ME!
	 */
	public static String getCanoncialTimezone(String timezoneStr) {
		if (timezoneStr == null) {
			return null;
		}

		timezoneStr = timezoneStr.trim();

		// Fix windows Daylight/Standard shift JDK doesn't map these (doh)

		int daylightIndex = StringUtils.indexOfIgnoreCase(timezoneStr,
				"DAYLIGHT");

		if (daylightIndex != -1) {
			StringBuffer timezoneBuf = new StringBuffer();
			timezoneBuf.append(timezoneStr.substring(0, daylightIndex));
			timezoneBuf.append("Standard");
			timezoneBuf.append(timezoneStr.substring(daylightIndex
					+ "DAYLIGHT".length(), timezoneStr.length()));
			timezoneStr = timezoneBuf.toString();
		}

		String canonicalTz = (String) TIMEZONE_MAPPINGS.get(timezoneStr);

		// if we didn't find it, try abbreviated timezones
		if (canonicalTz == null) {
			String[] abbreviatedTimezone = (String[]) ABBREVIATED_TIMEZONES
					.get(timezoneStr);

			if (abbreviatedTimezone != null) {
				// If there's only one mapping use that
				if (abbreviatedTimezone.length == 1) {
					canonicalTz = abbreviatedTimezone[0];
				} else {
					StringBuffer errorMsg = new StringBuffer(
							"The server timezone value '");
					errorMsg.append(timezoneStr);
					errorMsg
							.append("' represents more than one timezone. You must ");
					errorMsg
							.append("configure either the server or client to use a ");
					errorMsg
							.append("more specifc timezone value if you want to enable ");
					errorMsg.append("timezone support. The timezones that '");
					errorMsg.append(timezoneStr);
					errorMsg.append("' maps to are: ");
					errorMsg.append(abbreviatedTimezone[0]);

					for (int i = 1; i < abbreviatedTimezone.length; i++) {
						errorMsg.append(", ");
						errorMsg.append(abbreviatedTimezone[i]);
					}

					throw new IllegalArgumentException(errorMsg.toString());
				}
			}
		}

		return canonicalTz;
	}
}