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/* * 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.commons.lang3.time; import java.util.Calendar; import java.util.Date; import java.util.Locale; import java.util.TimeZone; /** * <p>Date and time formatting utilities and constants.</p> * * <p>Formatting is performed using the thread-safe * {@link org.apache.commons.lang3.time.FastDateFormat} class.</p> * * <p>Note that the JDK has a bug wherein calling Calendar.get(int) will * override any previously called Calendar.clear() calls. See LANG-755.</p> * * @since 2.0 * @version $Id$ */ public class DateFormatUtils { /** * The UTC time zone (often referred to as GMT). * This is private as it is mutable. */ private static final TimeZone UTC_TIME_ZONE = TimeZone.getTimeZone("GMT"); /** * ISO 8601 formatter for date-time without time zone. * The format used is {@code yyyy-MM-dd'T'HH:mm:ss}. * This format uses the default TimeZone in effect at the time of loading DateFormatUtils class. */ public static final FastDateFormat ISO_DATETIME_FORMAT = FastDateFormat.getInstance("yyyy-MM-dd'T'HH:mm:ss"); /** * ISO 8601 formatter for date-time with time zone. * The format used is {@code yyyy-MM-dd'T'HH:mm:ssZZ}. * This format uses the default TimeZone in effect at the time of loading DateFormatUtils class. */ public static final FastDateFormat ISO_DATETIME_TIME_ZONE_FORMAT = FastDateFormat .getInstance("yyyy-MM-dd'T'HH:mm:ssZZ"); /** * ISO 8601 formatter for date without time zone. * The format used is {@code yyyy-MM-dd}. * This format uses the default TimeZone in effect at the time of loading DateFormatUtils class. */ public static final FastDateFormat ISO_DATE_FORMAT = FastDateFormat.getInstance("yyyy-MM-dd"); /** * ISO 8601-like formatter for date with time zone. * The format used is {@code yyyy-MM-ddZZ}. * This pattern does not comply with the formal ISO 8601 specification * as the standard does not allow a time zone without a time. * This format uses the default TimeZone in effect at the time of loading DateFormatUtils class. */ public static final FastDateFormat ISO_DATE_TIME_ZONE_FORMAT = FastDateFormat.getInstance("yyyy-MM-ddZZ"); /** * ISO 8601 formatter for time without time zone. * The format used is {@code 'T'HH:mm:ss}. * This format uses the default TimeZone in effect at the time of loading DateFormatUtils class. */ public static final FastDateFormat ISO_TIME_FORMAT = FastDateFormat.getInstance("'T'HH:mm:ss"); /** * ISO 8601 formatter for time with time zone. * The format used is {@code 'T'HH:mm:ssZZ}. * This format uses the default TimeZone in effect at the time of loading DateFormatUtils class. */ public static final FastDateFormat ISO_TIME_TIME_ZONE_FORMAT = FastDateFormat.getInstance("'T'HH:mm:ssZZ"); /** * ISO 8601-like formatter for time without time zone. * The format used is {@code HH:mm:ss}. * This pattern does not comply with the formal ISO 8601 specification * as the standard requires the 'T' prefix for times. * This format uses the default TimeZone in effect at the time of loading DateFormatUtils class. */ public static final FastDateFormat ISO_TIME_NO_T_FORMAT = FastDateFormat.getInstance("HH:mm:ss"); /** * ISO 8601-like formatter for time with time zone. * The format used is {@code HH:mm:ssZZ}. * This pattern does not comply with the formal ISO 8601 specification * as the standard requires the 'T' prefix for times. * This format uses the default TimeZone in effect at the time of loading DateFormatUtils class. */ public static final FastDateFormat ISO_TIME_NO_T_TIME_ZONE_FORMAT = FastDateFormat.getInstance("HH:mm:ssZZ"); /** * SMTP (and probably other) date headers. * The format used is {@code EEE, dd MMM yyyy HH:mm:ss Z} in US locale. * This format uses the default TimeZone in effect at the time of loading DateFormatUtils class. */ public static final FastDateFormat SMTP_DATETIME_FORMAT = FastDateFormat .getInstance("EEE, dd MMM yyyy HH:mm:ss Z", Locale.US); //----------------------------------------------------------------------- /** * <p>DateFormatUtils instances should NOT be constructed in standard programming.</p> * * <p>This constructor is public to permit tools that require a JavaBean instance * to operate.</p> */ public DateFormatUtils() { super(); } /** * <p>Formats a date/time into a specific pattern using the UTC time zone.</p> * * @param millis the date to format expressed in milliseconds * @param pattern the pattern to use to format the date, not null * @return the formatted date */ public static String formatUTC(final long millis, final String pattern) { return format(new Date(millis), pattern, UTC_TIME_ZONE, null); } /** * <p>Formats a date/time into a specific pattern using the UTC time zone.</p> * * @param date the date to format, not null * @param pattern the pattern to use to format the date, not null * @return the formatted date */ public static String formatUTC(final Date date, final String pattern) { return format(date, pattern, UTC_TIME_ZONE, null); } /** * <p>Formats a date/time into a specific pattern using the UTC time zone.</p> * * @param millis the date to format expressed in milliseconds * @param pattern the pattern to use to format the date, not null * @param locale the locale to use, may be <code>null</code> * @return the formatted date */ public static String formatUTC(final long millis, final String pattern, final Locale locale) { return format(new Date(millis), pattern, UTC_TIME_ZONE, locale); } /** * <p>Formats a date/time into a specific pattern using the UTC time zone.</p> * * @param date the date to format, not null * @param pattern the pattern to use to format the date, not null * @param locale the locale to use, may be <code>null</code> * @return the formatted date */ public static String formatUTC(final Date date, final String pattern, final Locale locale) { return format(date, pattern, UTC_TIME_ZONE, locale); } /** * <p>Formats a date/time into a specific pattern.</p> * * @param millis the date to format expressed in milliseconds * @param pattern the pattern to use to format the date, not null * @return the formatted date */ public static String format(final long millis, final String pattern) { return format(new Date(millis), pattern, null, null); } /** * <p>Formats a date/time into a specific pattern.</p> * * @param date the date to format, not null * @param pattern the pattern to use to format the date, not null * @return the formatted date */ public static String format(final Date date, final String pattern) { return format(date, pattern, null, null); } /** * <p>Formats a calendar into a specific pattern.</p> * * @param calendar the calendar to format, not null * @param pattern the pattern to use to format the calendar, not null * @return the formatted calendar * @see FastDateFormat#format(Calendar) * @since 2.4 */ public static String format(final Calendar calendar, final String pattern) { return format(calendar, pattern, null, null); } /** * <p>Formats a date/time into a specific pattern in a time zone.</p> * * @param millis the time expressed in milliseconds * @param pattern the pattern to use to format the date, not null * @param timeZone the time zone to use, may be <code>null</code> * @return the formatted date */ public static String format(final long millis, final String pattern, final TimeZone timeZone) { return format(new Date(millis), pattern, timeZone, null); } /** * <p>Formats a date/time into a specific pattern in a time zone.</p> * * @param date the date to format, not null * @param pattern the pattern to use to format the date, not null * @param timeZone the time zone to use, may be <code>null</code> * @return the formatted date */ public static String format(final Date date, final String pattern, final TimeZone timeZone) { return format(date, pattern, timeZone, null); } /** * <p>Formats a calendar into a specific pattern in a time zone.</p> * * @param calendar the calendar to format, not null * @param pattern the pattern to use to format the calendar, not null * @param timeZone the time zone to use, may be <code>null</code> * @return the formatted calendar * @see FastDateFormat#format(Calendar) * @since 2.4 */ public static String format(final Calendar calendar, final String pattern, final TimeZone timeZone) { return format(calendar, pattern, timeZone, null); } /** * <p>Formats a date/time into a specific pattern in a locale.</p> * * @param millis the date to format expressed in milliseconds * @param pattern the pattern to use to format the date, not null * @param locale the locale to use, may be <code>null</code> * @return the formatted date */ public static String format(final long millis, final String pattern, final Locale locale) { return format(new Date(millis), pattern, null, locale); } /** * <p>Formats a date/time into a specific pattern in a locale.</p> * * @param date the date to format, not null * @param pattern the pattern to use to format the date, not null * @param locale the locale to use, may be <code>null</code> * @return the formatted date */ public static String format(final Date date, final String pattern, final Locale locale) { return format(date, pattern, null, locale); } /** * <p>Formats a calendar into a specific pattern in a locale.</p> * * @param calendar the calendar to format, not null * @param pattern the pattern to use to format the calendar, not null * @param locale the locale to use, may be <code>null</code> * @return the formatted calendar * @see FastDateFormat#format(Calendar) * @since 2.4 */ public static String format(final Calendar calendar, final String pattern, final Locale locale) { return format(calendar, pattern, null, locale); } /** * <p>Formats a date/time into a specific pattern in a time zone and locale.</p> * * @param millis the date to format expressed in milliseconds * @param pattern the pattern to use to format the date, not null * @param timeZone the time zone to use, may be <code>null</code> * @param locale the locale to use, may be <code>null</code> * @return the formatted date */ public static String format(final long millis, final String pattern, final TimeZone timeZone, final Locale locale) { return format(new Date(millis), pattern, timeZone, locale); } /** * <p>Formats a date/time into a specific pattern in a time zone and locale.</p> * * @param date the date to format, not null * @param pattern the pattern to use to format the date, not null, not null * @param timeZone the time zone to use, may be <code>null</code> * @param locale the locale to use, may be <code>null</code> * @return the formatted date */ public static String format(final Date date, final String pattern, final TimeZone timeZone, final Locale locale) { final FastDateFormat df = FastDateFormat.getInstance(pattern, timeZone, locale); return df.format(date); } /** * <p>Formats a calendar into a specific pattern in a time zone and locale.</p> * * @param calendar the calendar to format, not null * @param pattern the pattern to use to format the calendar, not null * @param timeZone the time zone to use, may be <code>null</code> * @param locale the locale to use, may be <code>null</code> * @return the formatted calendar * @see FastDateFormat#format(Calendar) * @since 2.4 */ public static String format(final Calendar calendar, final String pattern, final TimeZone timeZone, final Locale locale) { final FastDateFormat df = FastDateFormat.getInstance(pattern, timeZone, locale); return df.format(calendar); } }