Java tutorial
/* * Copyright (c) 1996, 2019, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code 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 * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ /* * (C) Copyright Taligent, Inc. 1996 - All Rights Reserved * (C) Copyright IBM Corp. 1996 - All Rights Reserved * * The original version of this source code and documentation is copyrighted * and owned by Taligent, Inc., a wholly-owned subsidiary of IBM. These * materials are provided under terms of a License Agreement between Taligent * and Sun. This technology is protected by multiple US and International * patents. This notice and attribution to Taligent may not be removed. * Taligent is a registered trademark of Taligent, Inc. * */ package java.text; import java.io.InvalidObjectException; import java.text.spi.DateFormatProvider; 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.MissingResourceException; import java.util.ResourceBundle; import java.util.TimeZone; import java.util.spi.LocaleServiceProvider; import sun.util.locale.provider.LocaleProviderAdapter; import sun.util.locale.provider.LocaleServiceProviderPool; /** * {@code DateFormat} is an abstract class for date/time formatting subclasses which * formats and parses dates or time in a language-independent manner. * The date/time formatting subclass, such as {@link SimpleDateFormat}, allows for * formatting (i.e., date → text), parsing (text → date), and * normalization. The date is represented as a <code>Date</code> object or * as the milliseconds since January 1, 1970, 00:00:00 GMT. * * <p>{@code DateFormat} provides many class methods for obtaining default date/time * formatters based on the default or a given locale and a number of formatting * styles. The formatting styles include {@link #FULL}, {@link #LONG}, {@link #MEDIUM}, and {@link #SHORT}. More * detail and examples of using these styles are provided in the method * descriptions. * * <p>{@code DateFormat} helps you to format and parse dates for any locale. * Your code can be completely independent of the locale conventions for * months, days of the week, or even the calendar format: lunar vs. solar. * * <p>To format a date for the current Locale, use one of the * static factory methods: * <blockquote> * <pre>{@code * myString = DateFormat.getDateInstance().format(myDate); * }</pre> * </blockquote> * <p>If you are formatting multiple dates, it is * more efficient to get the format and use it multiple times so that * the system doesn't have to fetch the information about the local * language and country conventions multiple times. * <blockquote> * <pre>{@code * DateFormat df = DateFormat.getDateInstance(); * for (int i = 0; i < myDate.length; ++i) { * output.println(df.format(myDate[i]) + "; "); * } * }</pre> * </blockquote> * <p>To format a date for a different Locale, specify it in the * call to {@link #getDateInstance(int, Locale) getDateInstance()}. * <blockquote> * <pre>{@code * DateFormat df = DateFormat.getDateInstance(DateFormat.LONG, Locale.FRANCE); * }</pre> * </blockquote> * * <p>If the specified locale contains "ca" (calendar), "rg" (region override), * and/or "tz" (timezone) <a href="../util/Locale.html#def_locale_extension">Unicode * extensions</a>, the calendar, the country and/or the time zone for formatting * are overridden. If both "ca" and "rg" are specified, the calendar from the "ca" * extension supersedes the implicit one from the "rg" extension. * * <p>You can use a DateFormat to parse also. * <blockquote> * <pre>{@code * myDate = df.parse(myString); * }</pre> * </blockquote> * <p>Use {@code getDateInstance} to get the normal date format for that country. * There are other static factory methods available. * Use {@code getTimeInstance} to get the time format for that country. * Use {@code getDateTimeInstance} to get a date and time format. You can pass in * different options to these factory methods to control the length of the * result; from {@link #SHORT} to {@link #MEDIUM} to {@link #LONG} to {@link #FULL}. The exact result depends * on the locale, but generally: * <ul><li>{@link #SHORT} is completely numeric, such as {@code 12.13.52} or {@code 3:30pm} * <li>{@link #MEDIUM} is longer, such as {@code Jan 12, 1952} * <li>{@link #LONG} is longer, such as {@code January 12, 1952} or {@code 3:30:32pm} * <li>{@link #FULL} is pretty completely specified, such as * {@code Tuesday, April 12, 1952 AD or 3:30:42pm PST}. * </ul> * * <p>You can also set the time zone on the format if you wish. * If you want even more control over the format or parsing, * (or want to give your users more control), * you can try casting the {@code DateFormat} you get from the factory methods * to a {@link SimpleDateFormat}. This will work for the majority * of countries; just remember to put it in a {@code try} block in case you * encounter an unusual one. * * <p>You can also use forms of the parse and format methods with * {@link ParsePosition} and {@link FieldPosition} to * allow you to * <ul><li>progressively parse through pieces of a string. * <li>align any particular field, or find out where it is for selection * on the screen. * </ul> * * <h2><a id="synchronization">Synchronization</a></h2> * * <p> * Date formats are not synchronized. * It is recommended to create separate format instances for each thread. * If multiple threads access a format concurrently, it must be synchronized * externally. * * @implSpec * <ul><li>The {@link #format(Date, StringBuffer, FieldPosition)} and * {@link #parse(String, ParsePosition)} methods may throw * {@code NullPointerException}, if any of their parameter is {@code null}. * The subclass may provide its own implementation and specification about * {@code NullPointerException}.</li> * <li>The {@link #setCalendar(Calendar)}, {@link * #setNumberFormat(NumberFormat)} and {@link #setTimeZone(TimeZone)} methods * do not throw {@code NullPointerException} when their parameter is * {@code null}, but any subsequent operations on the same instance may throw * {@code NullPointerException}.</li> * <li>The {@link #getCalendar()}, {@link #getNumberFormat()} and * {@link getTimeZone()} methods may return {@code null}, if the respective * values of this instance is set to {@code null} through the corresponding * setter methods. For Example: {@link #getTimeZone()} may return {@code null}, * if the {@code TimeZone} value of this instance is set as * {@link #setTimeZone(java.util.TimeZone) setTimeZone(null)}.</li> * </ul> * * @see Format * @see NumberFormat * @see SimpleDateFormat * @see java.util.Calendar * @see java.util.GregorianCalendar * @see java.util.TimeZone * @author Mark Davis, Chen-Lieh Huang, Alan Liu * @since 1.1 */ public abstract class DateFormat extends Format { /** * The {@link Calendar} instance used for calculating the date-time fields * and the instant of time. This field is used for both formatting and * parsing. * * <p>Subclasses should initialize this field to a {@link Calendar} * appropriate for the {@link Locale} associated with this * <code>DateFormat</code>. * @serial */ protected Calendar calendar; /** * The number formatter that <code>DateFormat</code> uses to format numbers * in dates and times. Subclasses should initialize this to a number format * appropriate for the locale associated with this <code>DateFormat</code>. * @serial */ protected NumberFormat numberFormat; /** * Useful constant for ERA field alignment. * Used in FieldPosition of date/time formatting. */ public static final int ERA_FIELD = 0; /** * Useful constant for YEAR field alignment. * Used in FieldPosition of date/time formatting. */ public static final int YEAR_FIELD = 1; /** * Useful constant for MONTH field alignment. * Used in FieldPosition of date/time formatting. */ public static final int MONTH_FIELD = 2; /** * Useful constant for DATE field alignment. * Used in FieldPosition of date/time formatting. */ public static final int DATE_FIELD = 3; /** * Useful constant for one-based HOUR_OF_DAY field alignment. * Used in FieldPosition of date/time formatting. * HOUR_OF_DAY1_FIELD is used for the one-based 24-hour clock. * For example, 23:59 + 01:00 results in 24:59. */ public static final int HOUR_OF_DAY1_FIELD = 4; /** * Useful constant for zero-based HOUR_OF_DAY field alignment. * Used in FieldPosition of date/time formatting. * HOUR_OF_DAY0_FIELD is used for the zero-based 24-hour clock. * For example, 23:59 + 01:00 results in 00:59. */ public static final int HOUR_OF_DAY0_FIELD = 5; /** * Useful constant for MINUTE field alignment. * Used in FieldPosition of date/time formatting. */ public static final int MINUTE_FIELD = 6; /** * Useful constant for SECOND field alignment. * Used in FieldPosition of date/time formatting. */ public static final int SECOND_FIELD = 7; /** * Useful constant for MILLISECOND field alignment. * Used in FieldPosition of date/time formatting. */ public static final int MILLISECOND_FIELD = 8; /** * Useful constant for DAY_OF_WEEK field alignment. * Used in FieldPosition of date/time formatting. */ public static final int DAY_OF_WEEK_FIELD = 9; /** * Useful constant for DAY_OF_YEAR field alignment. * Used in FieldPosition of date/time formatting. */ public static final int DAY_OF_YEAR_FIELD = 10; /** * Useful constant for DAY_OF_WEEK_IN_MONTH field alignment. * Used in FieldPosition of date/time formatting. */ public static final int DAY_OF_WEEK_IN_MONTH_FIELD = 11; /** * Useful constant for WEEK_OF_YEAR field alignment. * Used in FieldPosition of date/time formatting. */ public static final int WEEK_OF_YEAR_FIELD = 12; /** * Useful constant for WEEK_OF_MONTH field alignment. * Used in FieldPosition of date/time formatting. */ public static final int WEEK_OF_MONTH_FIELD = 13; /** * Useful constant for AM_PM field alignment. * Used in FieldPosition of date/time formatting. */ public static final int AM_PM_FIELD = 14; /** * Useful constant for one-based HOUR field alignment. * Used in FieldPosition of date/time formatting. * HOUR1_FIELD is used for the one-based 12-hour clock. * For example, 11:30 PM + 1 hour results in 12:30 AM. */ public static final int HOUR1_FIELD = 15; /** * Useful constant for zero-based HOUR field alignment. * Used in FieldPosition of date/time formatting. * HOUR0_FIELD is used for the zero-based 12-hour clock. * For example, 11:30 PM + 1 hour results in 00:30 AM. */ public static final int HOUR0_FIELD = 16; /** * Useful constant for TIMEZONE field alignment. * Used in FieldPosition of date/time formatting. */ public static final int TIMEZONE_FIELD = 17; // Proclaim serial compatibility with 1.1 FCS private static final long serialVersionUID = 7218322306649953788L; /** * Formats the given {@code Object} into a date-time string. The formatted * string is appended to the given {@code StringBuffer}. * * @param obj Must be a {@code Date} or a {@code Number} representing a * millisecond offset from the <a href="../util/Calendar.html#Epoch">Epoch</a>. * @param toAppendTo The string buffer for the returning date-time string. * @param fieldPosition keeps track on the position of the field within * the returned string. For example, given a date-time text * {@code "1996.07.10 AD at 15:08:56 PDT"}, if the given {@code fieldPosition} * is {@link DateFormat#YEAR_FIELD}, the begin index and end index of * {@code fieldPosition} will be set to 0 and 4, respectively. * Notice that if the same date-time field appears more than once in a * pattern, the {@code fieldPosition} will be set for the first occurrence * of that date-time field. For instance, formatting a {@code Date} to the * date-time string {@code "1 PM PDT (Pacific Daylight Time)"} using the * pattern {@code "h a z (zzzz)"} and the alignment field * {@link DateFormat#TIMEZONE_FIELD}, the begin index and end index of * {@code fieldPosition} will be set to 5 and 8, respectively, for the * first occurrence of the timezone pattern character {@code 'z'}. * @return the string buffer passed in as {@code toAppendTo}, * with formatted text appended. * @exception IllegalArgumentException if the {@code Format} cannot format * the given {@code obj}. * @see java.text.Format */ public final StringBuffer format(Object obj, StringBuffer toAppendTo, FieldPosition fieldPosition) { if (obj instanceof Date) return format((Date) obj, toAppendTo, fieldPosition); else if (obj instanceof Number) return format(new Date(((Number) obj).longValue()), toAppendTo, fieldPosition); else throw new IllegalArgumentException("Cannot format given Object as a Date"); } /** * Formats a {@link Date} into a date-time string. The formatted * string is appended to the given {@code StringBuffer}. * * @param date a Date to be formatted into a date-time string. * @param toAppendTo the string buffer for the returning date-time string. * @param fieldPosition keeps track on the position of the field within * the returned string. For example, given a date-time text * {@code "1996.07.10 AD at 15:08:56 PDT"}, if the given {@code fieldPosition} * is {@link DateFormat#YEAR_FIELD}, the begin index and end index of * {@code fieldPosition} will be set to 0 and 4, respectively. * Notice that if the same date-time field appears more than once in a * pattern, the {@code fieldPosition} will be set for the first occurrence * of that date-time field. For instance, formatting a {@code Date} to the * date-time string {@code "1 PM PDT (Pacific Daylight Time)"} using the * pattern {@code "h a z (zzzz)"} and the alignment field * {@link DateFormat#TIMEZONE_FIELD}, the begin index and end index of * {@code fieldPosition} will be set to 5 and 8, respectively, for the * first occurrence of the timezone pattern character {@code 'z'}. * @return the string buffer passed in as {@code toAppendTo}, with formatted * text appended. */ public abstract StringBuffer format(Date date, StringBuffer toAppendTo, FieldPosition fieldPosition); /** * Formats a {@link Date} into a date-time string. * * @param date the time value to be formatted into a date-time string. * @return the formatted date-time string. */ public final String format(Date date) { return format(date, new StringBuffer(), DontCareFieldPosition.INSTANCE).toString(); } /** * Parses text from the beginning of the given string to produce a date. * The method may not use the entire text of the given string. * <p> * See the {@link #parse(String, ParsePosition)} method for more information * on date parsing. * * @param source A <code>String</code> whose beginning should be parsed. * @return A <code>Date</code> parsed from the string. * @exception ParseException if the beginning of the specified string * cannot be parsed. */ public Date parse(String source) throws ParseException { ParsePosition pos = new ParsePosition(0); Date result = parse(source, pos); if (pos.index == 0) throw new ParseException("Unparseable date: \"" + source + "\"", pos.errorIndex); return result; } /** * Parse a date/time string according to the given parse position. For * example, a time text {@code "07/10/96 4:5 PM, PDT"} will be parsed into a {@code Date} * that is equivalent to {@code Date(837039900000L)}. * * <p> By default, parsing is lenient: If the input is not in the form used * by this object's format method but can still be parsed as a date, then * the parse succeeds. Clients may insist on strict adherence to the * format by calling {@link #setLenient(boolean) setLenient(false)}. * * <p>This parsing operation uses the {@link #calendar} to produce * a {@code Date}. As a result, the {@code calendar}'s date-time * fields and the {@code TimeZone} value may have been * overwritten, depending on subclass implementations. Any {@code * TimeZone} value that has previously been set by a call to * {@link #setTimeZone(java.util.TimeZone) setTimeZone} may need * to be restored for further operations. * * @param source The date/time string to be parsed * * @param pos On input, the position at which to start parsing; on * output, the position at which parsing terminated, or the * start position if the parse failed. * * @return A {@code Date}, or {@code null} if the input could not be parsed */ public abstract Date parse(String source, ParsePosition pos); /** * Parses text from a string to produce a <code>Date</code>. * <p> * The method attempts to parse text starting at the index given by * <code>pos</code>. * If parsing succeeds, then the index of <code>pos</code> is updated * to the index after the last character used (parsing does not necessarily * use all characters up to the end of the string), and the parsed * date is returned. The updated <code>pos</code> can be used to * indicate the starting point for the next call to this method. * If an error occurs, then the index of <code>pos</code> is not * changed, the error index of <code>pos</code> is set to the index of * the character where the error occurred, and null is returned. * <p> * See the {@link #parse(String, ParsePosition)} method for more information * on date parsing. * * @param source A <code>String</code>, part of which should be parsed. * @param pos A <code>ParsePosition</code> object with index and error * index information as described above. * @return A <code>Date</code> parsed from the string. In case of * error, returns null. * @throws NullPointerException if {@code source} or {@code pos} is null. */ public Object parseObject(String source, ParsePosition pos) { return parse(source, pos); } /** * Constant for full style pattern. */ public static final int FULL = 0; /** * Constant for long style pattern. */ public static final int LONG = 1; /** * Constant for medium style pattern. */ public static final int MEDIUM = 2; /** * Constant for short style pattern. */ public static final int SHORT = 3; /** * Constant for default style pattern. Its value is MEDIUM. */ public static final int DEFAULT = MEDIUM; /** * Gets the time formatter with the default formatting style * for the default {@link java.util.Locale.Category#FORMAT FORMAT} locale. * <p>This is equivalent to calling * {@link #getTimeInstance(int, Locale) getTimeInstance(DEFAULT, * Locale.getDefault(Locale.Category.FORMAT))}. * @see java.util.Locale#getDefault(java.util.Locale.Category) * @see java.util.Locale.Category#FORMAT * @return a time formatter. */ public static final DateFormat getTimeInstance() { return get(DEFAULT, 0, 1, Locale.getDefault(Locale.Category.FORMAT)); } /** * Gets the time formatter with the given formatting style * for the default {@link java.util.Locale.Category#FORMAT FORMAT} locale. * <p>This is equivalent to calling * {@link #getTimeInstance(int, Locale) getTimeInstance(style, * Locale.getDefault(Locale.Category.FORMAT))}. * @see java.util.Locale#getDefault(java.util.Locale.Category) * @see java.util.Locale.Category#FORMAT * @param style the given formatting style. For example, * SHORT for "h:mm a" in the US locale. * @return a time formatter. */ public static final DateFormat getTimeInstance(int style) { return get(style, 0, 1, Locale.getDefault(Locale.Category.FORMAT)); } /** * Gets the time formatter with the given formatting style * for the given locale. * @param style the given formatting style. For example, * SHORT for "h:mm a" in the US locale. * @param aLocale the given locale. * @return a time formatter. */ public static final DateFormat getTimeInstance(int style, Locale aLocale) { return get(style, 0, 1, aLocale); } /** * Gets the date formatter with the default formatting style * for the default {@link java.util.Locale.Category#FORMAT FORMAT} locale. * <p>This is equivalent to calling * {@link #getDateInstance(int, Locale) getDateInstance(DEFAULT, * Locale.getDefault(Locale.Category.FORMAT))}. * @see java.util.Locale#getDefault(java.util.Locale.Category) * @see java.util.Locale.Category#FORMAT * @return a date formatter. */ public static final DateFormat getDateInstance() { return get(0, DEFAULT, 2, Locale.getDefault(Locale.Category.FORMAT)); } /** * Gets the date formatter with the given formatting style * for the default {@link java.util.Locale.Category#FORMAT FORMAT} locale. * <p>This is equivalent to calling * {@link #getDateInstance(int, Locale) getDateInstance(style, * Locale.getDefault(Locale.Category.FORMAT))}. * @see java.util.Locale#getDefault(java.util.Locale.Category) * @see java.util.Locale.Category#FORMAT * @param style the given formatting style. For example, * SHORT for "M/d/yy" in the US locale. * @return a date formatter. */ public static final DateFormat getDateInstance(int style) { return get(0, style, 2, Locale.getDefault(Locale.Category.FORMAT)); } /** * Gets the date formatter with the given formatting style * for the given locale. * @param style the given formatting style. For example, * SHORT for "M/d/yy" in the US locale. * @param aLocale the given locale. * @return a date formatter. */ public static final DateFormat getDateInstance(int style, Locale aLocale) { return get(0, style, 2, aLocale); } /** * Gets the date/time formatter with the default formatting style * for the default {@link java.util.Locale.Category#FORMAT FORMAT} locale. * <p>This is equivalent to calling * {@link #getDateTimeInstance(int, int, Locale) getDateTimeInstance(DEFAULT, * DEFAULT, Locale.getDefault(Locale.Category.FORMAT))}. * @see java.util.Locale#getDefault(java.util.Locale.Category) * @see java.util.Locale.Category#FORMAT * @return a date/time formatter. */ public static final DateFormat getDateTimeInstance() { return get(DEFAULT, DEFAULT, 3, Locale.getDefault(Locale.Category.FORMAT)); } /** * Gets the date/time formatter with the given date and time * formatting styles for the default {@link java.util.Locale.Category#FORMAT FORMAT} locale. * <p>This is equivalent to calling * {@link #getDateTimeInstance(int, int, Locale) getDateTimeInstance(dateStyle, * timeStyle, Locale.getDefault(Locale.Category.FORMAT))}. * @see java.util.Locale#getDefault(java.util.Locale.Category) * @see java.util.Locale.Category#FORMAT * @param dateStyle the given date formatting style. For example, * SHORT for "M/d/yy" in the US locale. * @param timeStyle the given time formatting style. For example, * SHORT for "h:mm a" in the US locale. * @return a date/time formatter. */ public static final DateFormat getDateTimeInstance(int dateStyle, int timeStyle) { return get(timeStyle, dateStyle, 3, Locale.getDefault(Locale.Category.FORMAT)); } /** * Gets the date/time formatter with the given formatting styles * for the given locale. * @param dateStyle the given date formatting style. * @param timeStyle the given time formatting style. * @param aLocale the given locale. * @return a date/time formatter. */ public static final DateFormat getDateTimeInstance(int dateStyle, int timeStyle, Locale aLocale) { return get(timeStyle, dateStyle, 3, aLocale); } /** * Get a default date/time formatter that uses the SHORT style for both the * date and the time. * * @return a date/time formatter */ public static final DateFormat getInstance() { return getDateTimeInstance(SHORT, SHORT); } /** * Returns an array of all locales for which the * <code>get*Instance</code> methods of this class can return * localized instances. * The returned array represents the union of locales supported by the Java * runtime and by installed * {@link java.text.spi.DateFormatProvider DateFormatProvider} implementations. * It must contain at least a <code>Locale</code> instance equal to * {@link java.util.Locale#US Locale.US}. * * @return An array of locales for which localized * <code>DateFormat</code> instances are available. */ public static Locale[] getAvailableLocales() { LocaleServiceProviderPool pool = LocaleServiceProviderPool.getPool(DateFormatProvider.class); return pool.getAvailableLocales(); } /** * Set the calendar to be used by this date format. Initially, the default * calendar for the specified or default locale is used. * * <p>Any {@link java.util.TimeZone TimeZone} and {@linkplain * #isLenient() leniency} values that have previously been set are * overwritten by {@code newCalendar}'s values. * * @param newCalendar the new {@code Calendar} to be used by the date format */ public void setCalendar(Calendar newCalendar) { this.calendar = newCalendar; } /** * Gets the calendar associated with this date/time formatter. * * @return the calendar associated with this date/time formatter. */ public Calendar getCalendar() { return calendar; } /** * Allows you to set the number formatter. * @param newNumberFormat the given new NumberFormat. */ public void setNumberFormat(NumberFormat newNumberFormat) { this.numberFormat = newNumberFormat; } /** * Gets the number formatter which this date/time formatter uses to * format and parse a time. * @return the number formatter which this date/time formatter uses. */ public NumberFormat getNumberFormat() { return numberFormat; } /** * Sets the time zone for the calendar of this {@code DateFormat} object. * This method is equivalent to the following call. * <blockquote><pre>{@code * getCalendar().setTimeZone(zone) * }</pre></blockquote> * * <p>The {@code TimeZone} set by this method is overwritten by a * {@link #setCalendar(java.util.Calendar) setCalendar} call. * * <p>The {@code TimeZone} set by this method may be overwritten as * a result of a call to the parse method. * * @param zone the given new time zone. */ public void setTimeZone(TimeZone zone) { calendar.setTimeZone(zone); } /** * Gets the time zone. * This method is equivalent to the following call. * <blockquote><pre>{@code * getCalendar().getTimeZone() * }</pre></blockquote> * * @return the time zone associated with the calendar of DateFormat. */ public TimeZone getTimeZone() { return calendar.getTimeZone(); } /** * Specify whether or not date/time parsing is to be lenient. With * lenient parsing, the parser may use heuristics to interpret inputs that * do not precisely match this object's format. With strict parsing, * inputs must match this object's format. * * <p>This method is equivalent to the following call. * <blockquote><pre>{@code * getCalendar().setLenient(lenient) * }</pre></blockquote> * * <p>This leniency value is overwritten by a call to {@link * #setCalendar(java.util.Calendar) setCalendar()}. * * @param lenient when {@code true}, parsing is lenient * @see java.util.Calendar#setLenient(boolean) */ public void setLenient(boolean lenient) { calendar.setLenient(lenient); } /** * Tell whether date/time parsing is to be lenient. * This method is equivalent to the following call. * <blockquote><pre>{@code * getCalendar().isLenient() * }</pre></blockquote> * * @return {@code true} if the {@link #calendar} is lenient; * {@code false} otherwise. * @see java.util.Calendar#isLenient() */ public boolean isLenient() { return calendar.isLenient(); } /** * Overrides hashCode */ public int hashCode() { return numberFormat.hashCode(); // just enough fields for a reasonable distribution } /** * Overrides equals */ public boolean equals(Object obj) { if (this == obj) return true; if (obj == null || getClass() != obj.getClass()) return false; DateFormat other = (DateFormat) obj; return (// calendar.equivalentTo(other.calendar) // THIS API DOESN'T EXIST YET! calendar.getFirstDayOfWeek() == other.calendar.getFirstDayOfWeek() && calendar.getMinimalDaysInFirstWeek() == other.calendar.getMinimalDaysInFirstWeek() && calendar.isLenient() == other.calendar.isLenient() && calendar.getTimeZone().equals(other.calendar.getTimeZone()) && numberFormat.equals(other.numberFormat)); } /** * Overrides Cloneable */ public Object clone() { DateFormat other = (DateFormat) super.clone(); other.calendar = (Calendar) calendar.clone(); other.numberFormat = (NumberFormat) numberFormat.clone(); return other; } /** * Creates a DateFormat with the given time and/or date style in the given * locale. * @param timeStyle a value from 0 to 3 indicating the time format, * ignored if flags is 2 * @param dateStyle a value from 0 to 3 indicating the time format, * ignored if flags is 1 * @param flags either 1 for a time format, 2 for a date format, * or 3 for a date/time format * @param loc the locale for the format */ private static DateFormat get(int timeStyle, int dateStyle, int flags, Locale loc) { if ((flags & 1) != 0) { if (timeStyle < 0 || timeStyle > 3) { throw new IllegalArgumentException("Illegal time style " + timeStyle); } } else { timeStyle = -1; } if ((flags & 2) != 0) { if (dateStyle < 0 || dateStyle > 3) { throw new IllegalArgumentException("Illegal date style " + dateStyle); } } else { dateStyle = -1; } LocaleProviderAdapter adapter = LocaleProviderAdapter.getAdapter(DateFormatProvider.class, loc); DateFormat dateFormat = get(adapter, timeStyle, dateStyle, loc); if (dateFormat == null) { dateFormat = get(LocaleProviderAdapter.forJRE(), timeStyle, dateStyle, loc); } return dateFormat; } private static DateFormat get(LocaleProviderAdapter adapter, int timeStyle, int dateStyle, Locale loc) { DateFormatProvider provider = adapter.getDateFormatProvider(); DateFormat dateFormat; if (timeStyle == -1) { dateFormat = provider.getDateInstance(dateStyle, loc); } else { if (dateStyle == -1) { dateFormat = provider.getTimeInstance(timeStyle, loc); } else { dateFormat = provider.getDateTimeInstance(dateStyle, timeStyle, loc); } } return dateFormat; } /** * Create a new date format. */ protected DateFormat() { } /** * Defines constants that are used as attribute keys in the * <code>AttributedCharacterIterator</code> returned * from <code>DateFormat.formatToCharacterIterator</code> and as * field identifiers in <code>FieldPosition</code>. * <p> * The class also provides two methods to map * between its constants and the corresponding Calendar constants. * * @since 1.4 * @see java.util.Calendar */ public static class Field extends Format.Field { // Proclaim serial compatibility with 1.4 FCS private static final long serialVersionUID = 7441350119349544720L; // table of all instances in this class, used by readResolve private static final Map<String, Field> instanceMap = new HashMap<>(18); // Maps from Calendar constant (such as Calendar.ERA) to Field // constant (such as Field.ERA). private static final Field[] calendarToFieldMapping = new Field[Calendar.FIELD_COUNT]; /** Calendar field. */ private int calendarField; /** * Returns the <code>Field</code> constant that corresponds to * the <code>Calendar</code> constant <code>calendarField</code>. * If there is no direct mapping between the <code>Calendar</code> * constant and a <code>Field</code>, null is returned. * * @throws IllegalArgumentException if <code>calendarField</code> is * not the value of a <code>Calendar</code> field constant. * @param calendarField Calendar field constant * @return Field instance representing calendarField. * @see java.util.Calendar */ public static Field ofCalendarField(int calendarField) { if (calendarField < 0 || calendarField >= calendarToFieldMapping.length) { throw new IllegalArgumentException("Unknown Calendar constant " + calendarField); } return calendarToFieldMapping[calendarField]; } /** * Creates a <code>Field</code>. * * @param name the name of the <code>Field</code> * @param calendarField the <code>Calendar</code> constant this * <code>Field</code> corresponds to; any value, even one * outside the range of legal <code>Calendar</code> values may * be used, but <code>-1</code> should be used for values * that don't correspond to legal <code>Calendar</code> values */ protected Field(String name, int calendarField) { super(name); this.calendarField = calendarField; if (this.getClass() == DateFormat.Field.class) { instanceMap.put(name, this); if (calendarField >= 0) { // assert(calendarField < Calendar.FIELD_COUNT); calendarToFieldMapping[calendarField] = this; } } } /** * Returns the <code>Calendar</code> field associated with this * attribute. For example, if this represents the hours field of * a <code>Calendar</code>, this would return * <code>Calendar.HOUR</code>. If there is no corresponding * <code>Calendar</code> constant, this will return -1. * * @return Calendar constant for this field * @see java.util.Calendar */ public int getCalendarField() { return calendarField; } /** * Resolves instances being deserialized to the predefined constants. * * @throws InvalidObjectException if the constant could not be * resolved. * @return resolved DateFormat.Field constant */ @Override protected Object readResolve() throws InvalidObjectException { if (this.getClass() != DateFormat.Field.class) { throw new InvalidObjectException("subclass didn't correctly implement readResolve"); } Object instance = instanceMap.get(getName()); if (instance != null) { return instance; } else { throw new InvalidObjectException("unknown attribute name"); } } // // The constants // /** * Constant identifying the era field. */ public static final Field ERA = new Field("era", Calendar.ERA); /** * Constant identifying the year field. */ public static final Field YEAR = new Field("year", Calendar.YEAR); /** * Constant identifying the month field. */ public static final Field MONTH = new Field("month", Calendar.MONTH); /** * Constant identifying the day of month field. */ public static final Field DAY_OF_MONTH = new Field("day of month", Calendar.DAY_OF_MONTH); /** * Constant identifying the hour of day field, where the legal values * are 1 to 24. */ public static final Field HOUR_OF_DAY1 = new Field("hour of day 1", -1); /** * Constant identifying the hour of day field, where the legal values * are 0 to 23. */ public static final Field HOUR_OF_DAY0 = new Field("hour of day", Calendar.HOUR_OF_DAY); /** * Constant identifying the minute field. */ public static final Field MINUTE = new Field("minute", Calendar.MINUTE); /** * Constant identifying the second field. */ public static final Field SECOND = new Field("second", Calendar.SECOND); /** * Constant identifying the millisecond field. */ public static final Field MILLISECOND = new Field("millisecond", Calendar.MILLISECOND); /** * Constant identifying the day of week field. */ public static final Field DAY_OF_WEEK = new Field("day of week", Calendar.DAY_OF_WEEK); /** * Constant identifying the day of year field. */ public static final Field DAY_OF_YEAR = new Field("day of year", Calendar.DAY_OF_YEAR); /** * Constant identifying the day of week field. */ public static final Field DAY_OF_WEEK_IN_MONTH = new Field("day of week in month", Calendar.DAY_OF_WEEK_IN_MONTH); /** * Constant identifying the week of year field. */ public static final Field WEEK_OF_YEAR = new Field("week of year", Calendar.WEEK_OF_YEAR); /** * Constant identifying the week of month field. */ public static final Field WEEK_OF_MONTH = new Field("week of month", Calendar.WEEK_OF_MONTH); /** * Constant identifying the time of day indicator * (e.g. "a.m." or "p.m.") field. */ public static final Field AM_PM = new Field("am pm", Calendar.AM_PM); /** * Constant identifying the hour field, where the legal values are * 1 to 12. */ public static final Field HOUR1 = new Field("hour 1", -1); /** * Constant identifying the hour field, where the legal values are * 0 to 11. */ public static final Field HOUR0 = new Field("hour", Calendar.HOUR); /** * Constant identifying the time zone field. */ public static final Field TIME_ZONE = new Field("time zone", -1); } }