Java tutorial
/* * Copyright 2008 Google Inc. * * Licensed 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 io.pelle.mango.client.core.utils; import java.util.HashMap; import java.util.Map; import com.google.gwt.i18n.shared.CustomDateTimeFormat; import com.google.gwt.i18n.shared.DateTimeFormatInfo; import com.google.gwt.i18n.shared.DefaultDateTimeFormatInfo; import com.google.gwt.i18n.shared.impl.cldr.DateTimeFormatInfoImpl_en; /** * Formats and parses dates and times using locale-sensitive patterns. * * <h3>Patterns</h3> * * <table> * <tr> * <th>Symbol</th> * <th>Meaning</th> * <th>Presentation</th> * <th>Example</th> * </tr> * * <tr> * <td><code>G</code></td> * <td>era designator</td> * <td>Text</td> * <td><code>AD</code></td> * </tr> * * <tr> * <td><code>y</code></td> * <td>year</td> * <td>Number</td> * <td><code>1996</code></td> * </tr> * * <tr> * <td><code>L</code></td> * <td>standalone month in year</td> * <td>Text or Number</td> * <td><code>July (or) 07</code></td> * </tr> * * <tr> * <td><code>M</code></td> * <td>month in year</td> * <td>Text or Number</td> * <td><code>July (or) 07</code></td> * </tr> * * <tr> * <td><code>d</code></td> * <td>day in month</td> * <td>Number</td> * <td><code>10</code></td> * </tr> * * <tr> * <td><code>h</code></td> * <td>hour in am/pm (1-12)</td> * <td>Number</td> * <td><code>12</code></td> * </tr> * * <tr> * <td><code>H</code></td> * <td>hour in day (0-23)</td> * <td>Number</td> * <td><code>0</code></td> * </tr> * * <tr> * <td><code>m</code></td> * <td>minute in hour</td> * <td>Number</td> * <td><code>30</code></td> * </tr> * * <tr> * <td><code>s</code></td> * <td>second in minute</td> * <td>Number</td> * <td><code>55</code></td> * </tr> * * <tr> * <td><code>S</code></td> * <td>fractional second</td> * <td>Number</td> * <td><code>978</code></td> * </tr> * * <tr> * <td><code>E</code></td> * <td>day of week</td> * <td>Text</td> * <td><code>Tuesday</code></td> * </tr> * * <tr> * <td><code>c</code></td> * <td>standalone day of week</td> * <td>Text</td> * <td><code>Tuesday</code></td> * </tr> * * <tr> * <td><code>a</code></td> * <td>am/pm marker</td> * <td>Text</td> * <td><code>PM</code></td> * </tr> * * <tr> * <td><code>k</code></td> * <td>hour in day (1-24)</td> * <td>Number</td> * <td><code>24</code></td> * </tr> * * <tr> * <td><code>K</code></td> * <td>hour in am/pm (0-11)</td> * <td>Number</td> * <td><code>0</code></td> * </tr> * * <tr> * <td><code>z</code></td> * <td>time zone</td> * <td>Text</td> * <td><code>Pacific Standard Time(see comment)</code></td> * </tr> * * <tr> * <td><code>Z</code></td> * <td>time zone (RFC 822)</td> * <td>Text</td> * <td><code>-0800(See comment)</code></td> * </tr> * * <tr> * <td><code>v</code></td> * <td>time zone id</td> * <td>Text</td> * <td><code>America/Los_Angeles(See comment)</code></td> * </tr> * * <tr> * <td><code>'</code></td> * <td>escape for text</td> * <td>Delimiter</td> * <td><code>'Date='</code></td> * </tr> * * <tr> * <td><code>''</code></td> * <td>single quote</td> * <td>Literal</td> * <td><code>'o''clock'</code></td> * </tr> * </table> * * <p> * The number of pattern letters influences the format, as follows: * </p> * * <dl> * <dt>Text</dt> * <dd>if 4 or more, then use the full form; if less than 4, use short or * abbreviated form if it exists (e.g., <code>"EEEE"</code> produces * <code>"Monday"</code>, <code>"EEE"</code> produces <code>"Mon"</code>)</dd> * * <dt>Number</dt> * <dd>the minimum number of digits. Shorter numbers are zero-padded to this * amount (e.g. if <code>"m"</code> produces <code>"6"</code>, <code>"mm"</code> * produces <code>"06"</code>). Year is handled specially; that is, if the count * of 'y' is 2, the Year will be truncated to 2 digits. (e.g., if * <code>"yyyy"</code> produces <code>"1997"</code>, <code>"yy"</code> produces * <code>"97"</code>.) Unlike other fields, fractional seconds are padded on the * right with zero.</dd> * * <dt>Text or Number</dt> * <dd>3 or more, use text, otherwise use number. (e.g. <code>"M"</code> * produces <code>"1"</code>, <code>"MM"</code> produces <code>"01"</code>, * <code>"MMM"</code> produces <code>"Jan"</code>, and <code>"MMMM"</code> * produces <code>"January"</code>. Some pattern letters also treat a count of 5 * specially, meaning a single-letter abbreviation: <code>L</code>, * <code>M</code>, <code>E</code>, and <code>c</code>.</dd> * </dl> * * <p> * Any characters in the pattern that are not in the ranges of ['<code>a</code> * '..'<code>z</code>'] and ['<code>A</code>'..'<code>Z</code>'] will be treated * as quoted text. For instance, characters like '<code>:</code>', ' * <code>.</code>', '<code> </code>' (space), '<code>#</code>' and ' * <code>@</code>' will appear in the resulting time text even they are not * embraced within single quotes. * </p> * * <p> * [Time Zone Handling] Web browsers don't provide all the information we need * for proper time zone formating -- so GWT has a copy of the required data, for * your convenience. For simpler cases, one can also use a fallback * implementation that only keeps track of the current timezone offset. These * two approaches are called, respectively, Common TimeZones and Simple * TimeZones, although both are implemented with the same TimeZone class. * * "TimeZone createTimeZone(String timezoneData)" returns a Common TimeZone * object, and "TimeZone createTimeZone(int timeZoneOffsetInMinutes)" returns a * Simple TimeZone object. The one provided by OS fall into to Simple TimeZone * category. For formatting purpose, following table shows the behavior of GWT * DateTimeFormat. * </p> * <table> * <tr> * <th>Pattern</th> * <th>Common TimeZone</th> * <th>Simple TimeZone</th> * </tr> * <tr> * <td>z, zz, zzz</td> * <td>PDT</td> * <td>UTC-7</td> * </tr> * <tr> * <td>zzzz</td> * <td>Pacific Daylight Time</td> * <td>UTC-7</td> * </tr> * <tr> * <td>Z, ZZ</td> * <td>-0700</td> * <td>-0700</td> * </tr> * <tr> * <td>ZZZ</td> * <td>-07:00</td> * <td>-07:00</td> * </tr> * <tr> * <td>ZZZZ</td> * <td>GMT-07:00</td> * <td>GMT-07:00</td> * </tr> * <tr> * <td>v, vv, vvv, vvvv</td> * <td>America/Los_Angeles</td> * <td>Etc/GMT+7</td> * </tr> * </table> * * <h3>Parsing Dates and Times</h3> * <p> * The pattern does not need to specify every field. If the year, month, or day * is missing from the pattern, the corresponding value will be taken from the * current date. If the month is specified but the day is not, the day will be * constrained to the last day within the specified month. If the hour, minute, * or second is missing, the value defaults to zero. * </p> * * <p> * As with formatting (described above), the count of pattern letters determines * the parsing behavior. * </p> * * <dl> * <dt>Text</dt> * <dd>4 or more pattern letters--use full form, less than 4--use short or * abbreviated form if one exists. In parsing, we will always try long format, * then short.</dd> * * <dt>Number</dt> * <dd>the minimum number of digits.</dd> * * <dt>Text or Number</dt> * <dd>3 or more characters means use text, otherwise use number</dd> * </dl> * * <p> * Although the current pattern specification doesn't not specify behavior for * all letters, it may in the future. It is strongly discouraged to use * unspecified letters as literal text without quoting them. * </p> * <p> * [Note on TimeZone] The time zone support for parsing is limited. Only * standard GMT and RFC format are supported. Time zone specification using time * zone id (like America/Los_Angeles), time zone names (like PST, Pacific * Standard Time) are not supported. Normally, it is too much a burden for a * client application to load all the time zone symbols. And in almost all those * cases, it is a better choice to do such parsing on server side through * certain RPC mechanism. This decision is based on particular use cases we have * studied; in principle, it could be changed in future versions. * </p> * * <h3>Examples</h3> * <table> * <tr> * <th>Pattern</th> * <th>Formatted Text</th> * </tr> * * <tr> * <td><code>"yyyy.MM.dd G 'at' HH:mm:ss vvvv"</code></td> * <td><code>1996.07.10 AD at 15:08:56 America/Los_Angeles</code></td> * </tr> * * <tr> * <td><code>"EEE, MMM d, ''yy"</code></td> * <td><code>Wed, July 10, '96</code></td> * </tr> * * <tr> * <td><code>"h:mm a"</code></td> * <td><code>12:08 PM</code></td> * </tr> * * <tr> * <td><code>"hh 'o''clock' a, zzzz"</code></td> * <td><code> 12 o'clock PM, Pacific Daylight Time</code></td> * </tr> * * <tr> * <td><code>"K:mm a, vvvv"</code></td> * <td><code> 0:00 PM, America/Los_Angeles</code></td> * </tr> * * <tr> * <td><code>"yyyyy.MMMMM.dd GGG hh:mm aaa"</code></td> * <td><code>01996.July.10 AD 12:08 PM</code></td> * </tr> * </table> * * <h3>Additional Parsing Considerations</h3> * <p> * When parsing a date string using the abbreviated year pattern ( * <code>"yy"</code>), the parser must interpret the abbreviated year relative * to some century. It does this by adjusting dates to be within 80 years before * and 20 years after the time the parser instance is created. For example, * using a pattern of <code>"MM/dd/yy"</code> and a <code>DateTimeFormat</code> * object created on Jan 1, 1997, the string <code>"01/11/12"</code> would be * interpreted as Jan 11, 2012 while the string <code>"05/04/64"</code> would be * interpreted as May 4, 1964. During parsing, only strings consisting of * exactly two digits, as defined by {@link java.lang.Character#isDigit(char)}, * will be parsed into the default century. If the year pattern does not have * exactly two 'y' characters, the year is interpreted literally, regardless of * the number of digits. For example, using the pattern * <code>"MM/dd/yyyy"</code>, "01/11/12" parses to Jan 11, 12 A.D. * </p> * * <p> * When numeric fields abut one another directly, with no intervening delimiter * characters, they constitute a run of abutting numeric fields. Such runs are * parsed specially. For example, the format "HHmmss" parses the input text * "123456" to 12:34:56, parses the input text "12345" to 1:23:45, and fails to * parse "1234". In other words, the leftmost field of the run is flexible, * while the others keep a fixed width. If the parse fails anywhere in the run, * then the leftmost field is shortened by one character, and the entire run is * parsed again. This is repeated until either the parse succeeds or the * leftmost field is one character in length. If the parse still fails at that * point, the parse of the run fails. * </p> * * <p> * In the current implementation, timezone parsing only supports * <code>GMT:hhmm</code>, <code>GMT:+hhmm</code>, and <code>GMT:-hhmm</code>. * </p> * * <h3>Example</h3> {@example com.google.gwt.examples.DateTimeFormatExample} * * deprecated use {@link com.google.gwt.i18n.shared.DateTimeFormat} instead */ // Temporarily remove deprecation to keep from breaking teams that don't allow // deprecated references. // @Deprecated public class DateTimeFormat extends com.google.gwt.i18n.shared.DateTimeFormat { private static final Map<String, DateTimeFormat> cache; static { cache = new HashMap<String, DateTimeFormat>(); } /** * Get a DateTimeFormat instance for a predefined format. * * <p> * See {@link CustomDateTimeFormat} if you need a localized format that is * not supported here. * * @param predef * {@link PredefinedFormat} describing desired format * @return a DateTimeFormat instance for the specified format */ public static com.google.gwt.i18n.shared.DateTimeFormat getFormat(PredefinedFormat predef) { if (usesFixedEnglishStrings(predef)) { String pattern; switch (predef) { case RFC_2822: pattern = com.google.gwt.i18n.shared.DateTimeFormat.RFC2822_PATTERN; break; case ISO_8601: pattern = com.google.gwt.i18n.shared.DateTimeFormat.ISO8601_PATTERN; break; default: throw new IllegalStateException("Unexpected predef type " + predef); } return getFormat(pattern, new DateTimeFormatInfoImpl_en()); } DateTimeFormatInfo dtfi = getDefaultDateTimeFormatInfo(); String pattern; switch (predef) { case DATE_FULL: pattern = dtfi.dateFormatFull(); break; case DATE_LONG: pattern = dtfi.dateFormatLong(); break; case DATE_MEDIUM: pattern = dtfi.dateFormatMedium(); break; case DATE_SHORT: pattern = dtfi.dateFormatShort(); break; case DATE_TIME_FULL: pattern = dtfi.dateTimeFull(dtfi.timeFormatFull(), dtfi.dateFormatFull()); break; case DATE_TIME_LONG: pattern = dtfi.dateTimeLong(dtfi.timeFormatLong(), dtfi.dateFormatLong()); break; case DATE_TIME_MEDIUM: pattern = dtfi.dateTimeMedium(dtfi.timeFormatMedium(), dtfi.dateFormatMedium()); break; case DATE_TIME_SHORT: pattern = dtfi.dateTimeShort(dtfi.timeFormatShort(), dtfi.dateFormatShort()); break; case DAY: pattern = dtfi.formatDay(); break; case HOUR24_MINUTE: pattern = dtfi.formatHour24Minute(); break; case HOUR24_MINUTE_SECOND: pattern = dtfi.formatHour24MinuteSecond(); break; case HOUR_MINUTE: pattern = dtfi.formatHour12Minute(); break; case HOUR_MINUTE_SECOND: pattern = dtfi.formatHour12MinuteSecond(); break; case MINUTE_SECOND: pattern = dtfi.formatMinuteSecond(); break; case MONTH: pattern = dtfi.formatMonthFull(); break; case MONTH_ABBR: pattern = dtfi.formatMonthAbbrev(); break; case MONTH_ABBR_DAY: pattern = dtfi.formatMonthAbbrevDay(); break; case MONTH_DAY: pattern = dtfi.formatMonthFullDay(); break; case MONTH_NUM_DAY: pattern = dtfi.formatMonthNumDay(); break; case MONTH_WEEKDAY_DAY: pattern = dtfi.formatMonthFullWeekdayDay(); break; case TIME_FULL: pattern = dtfi.timeFormatFull(); break; case TIME_LONG: pattern = dtfi.timeFormatLong(); break; case TIME_MEDIUM: pattern = dtfi.timeFormatMedium(); break; case TIME_SHORT: pattern = dtfi.timeFormatShort(); break; case YEAR: pattern = dtfi.formatYear(); break; case YEAR_MONTH: pattern = dtfi.formatYearMonthFull(); break; case YEAR_MONTH_ABBR: pattern = dtfi.formatYearMonthAbbrev(); break; case YEAR_MONTH_ABBR_DAY: pattern = dtfi.formatYearMonthAbbrevDay(); break; case YEAR_MONTH_DAY: pattern = dtfi.formatYearMonthFullDay(); break; case YEAR_MONTH_NUM: pattern = dtfi.formatYearMonthNum(); break; case YEAR_MONTH_NUM_DAY: pattern = dtfi.formatYearMonthNumDay(); break; case YEAR_MONTH_WEEKDAY_DAY: pattern = dtfi.formatYearMonthWeekdayDay(); break; case YEAR_QUARTER: pattern = dtfi.formatYearQuarterFull(); break; case YEAR_QUARTER_ABBR: pattern = dtfi.formatYearQuarterShort(); break; default: throw new IllegalArgumentException("Unexpected predefined format " + predef); } return getFormat(pattern, dtfi); } /** * Returns a DateTimeFormat object using the specified pattern. If you need * to format or parse repeatedly using the same pattern, it is highly * recommended that you cache the returned <code>DateTimeFormat</code> * object and reuse it rather than calling this method repeatedly. * * <p> * Note that the pattern supplied is used as-is -- for example, if you * supply "MM/dd/yyyy" as the pattern, that is the order you will get the * fields, even in locales where the order is different. It is recommended * to use {@link #getFormat(PredefinedFormat)} instead -- if you use this * method, you are taking responsibility for localizing the patterns * yourself. * * @param pattern * string to specify how the date should be formatted * * @return a <code>DateTimeFormat</code> object that can be used for format * or parse date/time values matching the specified pattern * * @throws IllegalArgumentException * if the specified pattern could not be parsed */ public static DateTimeFormat getFormat(String pattern) { return getFormat(pattern, getDefaultDateTimeFormatInfo()); } /** * Retrieve the DateTimeFormat object for full date format. The pattern for * this format is predefined for each locale. * * @return A DateTimeFormat object * @deprecated use {@link #getFormat(PredefinedFormat)} with * {@link PredefinedFormat#DATE_FULL} instead */ @Deprecated public static com.google.gwt.i18n.shared.DateTimeFormat getFullDateFormat() { return getFormat(PredefinedFormat.DATE_FULL); } /** * Retrieve the DateTimeFormat object for full date and time format. The * pattern for this format is predefined for each locale. * * @return A DateTimeFormat object * @deprecated use {@link #getFormat(PredefinedFormat)} with * {@link PredefinedFormat#DATE_TIME_FULL} instead */ @Deprecated public static com.google.gwt.i18n.shared.DateTimeFormat getFullDateTimeFormat() { return getFormat(PredefinedFormat.DATE_TIME_FULL); } /** * Retrieve the DateTimeFormat object for full time format. The pattern for * this format is predefined for each locale. * * @return A DateTimeFormat object * @deprecated use {@link #getFormat(PredefinedFormat)} with * {@link PredefinedFormat#TIME_FULL} instead */ @Deprecated public static com.google.gwt.i18n.shared.DateTimeFormat getFullTimeFormat() { return getFormat(PredefinedFormat.TIME_FULL); } /** * Retrieve the DateTimeFormat object for long date format. The pattern for * this format is predefined for each locale. * * @return A DateTimeFormat object * @deprecated use {@link #getFormat(PredefinedFormat)} with * {@link PredefinedFormat#DATE_LONG} instead */ @Deprecated public static com.google.gwt.i18n.shared.DateTimeFormat getLongDateFormat() { return getFormat(PredefinedFormat.DATE_LONG); } /** * Retrieve the DateTimeFormat object for long date and time format. The * pattern for this format is predefined for each locale. * * @return A DateTimeFormat object * @deprecated use {@link #getFormat(PredefinedFormat)} with * {@link PredefinedFormat#DATE_TIME_LONG} instead */ @Deprecated public static com.google.gwt.i18n.shared.DateTimeFormat getLongDateTimeFormat() { return getFormat(PredefinedFormat.DATE_TIME_LONG); } /** * Retrieve the DateTimeFormat object for long time format. The pattern for * this format is predefined for each locale. * * @return A DateTimeFormat object * @deprecated use {@link #getFormat(PredefinedFormat)} with * {@link PredefinedFormat#TIME_LONG} instead */ @Deprecated public static com.google.gwt.i18n.shared.DateTimeFormat getLongTimeFormat() { return getFormat(PredefinedFormat.TIME_LONG); } /** * Retrieve the DateTimeFormat object for medium date format. The pattern * for this format is predefined for each locale. * * @return A DateTimeFormat object * @deprecated use {@link #getFormat(PredefinedFormat)} with * {@link PredefinedFormat#DATE_MEDIUM} instead */ @Deprecated public static com.google.gwt.i18n.shared.DateTimeFormat getMediumDateFormat() { return getFormat(PredefinedFormat.DATE_MEDIUM); } /** * Retrieve the DateTimeFormat object for medium date and time format. The * pattern for this format is predefined for each locale. * * @return A DateTimeFormat object * @deprecated use {@link #getFormat(PredefinedFormat)} with * {@link PredefinedFormat#DATE_TIME_MEDIUM} instead */ @Deprecated public static com.google.gwt.i18n.shared.DateTimeFormat getMediumDateTimeFormat() { return getFormat(PredefinedFormat.DATE_TIME_MEDIUM); } /** * Retrieve the DateTimeFormat object for medium time format. The pattern * for this format is predefined for each locale. * * @return A DateTimeFormat object * @deprecated use {@link #getFormat(PredefinedFormat)} with * {@link PredefinedFormat#TIME_MEDIUM} instead */ @Deprecated public static com.google.gwt.i18n.shared.DateTimeFormat getMediumTimeFormat() { return getFormat(PredefinedFormat.TIME_MEDIUM); } /** * Retrieve the DateTimeFormat object for short date format. The pattern for * this format is predefined for each locale. * * @return A DateTimeFormat object * @deprecated use {@link #getFormat(PredefinedFormat)} with * {@link PredefinedFormat#DATE_SHORT} instead */ @Deprecated public static com.google.gwt.i18n.shared.DateTimeFormat getShortDateFormat() { return getFormat(PredefinedFormat.DATE_SHORT); } /** * Retrieve the DateTimeFormat object for short date and time format. The * pattern for this format is predefined for each locale. * * @return A DateTimeFormat object * @deprecated use {@link #getFormat(PredefinedFormat)} with * {@link PredefinedFormat#DATE_TIME_SHORT} instead */ @Deprecated public static com.google.gwt.i18n.shared.DateTimeFormat getShortDateTimeFormat() { return getFormat(PredefinedFormat.DATE_TIME_SHORT); } /** * Retrieve the DateTimeFormat object for short time format. The pattern for * this format is predefined for each locale. * * @return A DateTimeFormat object. * @deprecated use {@link #getFormat(PredefinedFormat)} with * {@link PredefinedFormat#TIME_SHORT} instead */ @Deprecated public static com.google.gwt.i18n.shared.DateTimeFormat getShortTimeFormat() { return getFormat(PredefinedFormat.TIME_SHORT); } /** * Internal factory method that provides caching. * * @param pattern * @param dtfi * @return DateTimeFormat instance */ protected static DateTimeFormat getFormat(String pattern, DateTimeFormatInfo dtfi) { DateTimeFormatInfo defaultDtfi = getDefaultDateTimeFormatInfo(); DateTimeFormat dtf = null; if (dtfi == defaultDtfi) { dtf = cache.get(pattern); } if (dtf == null) { dtf = new DateTimeFormat(pattern, dtfi); if (dtfi == defaultDtfi) { cache.put(pattern, dtf); } } return dtf; } private static DateTimeFormatInfo getDefaultDateTimeFormatInfo() { return new DefaultDateTimeFormatInfo(); } /** * Returns true if the predefined format is one that specifies always using * English names/separators. * <p> * This should be a method on PredefinedFormat, but that would defeat the * enum optimizations GWT is currently capable of. * * @param predef * @return true if the specified format requires English names/separators */ private static boolean usesFixedEnglishStrings(PredefinedFormat predef) { switch (predef) { case RFC_2822: return true; case ISO_8601: return true; default: return false; } } /** * Constructs a format object using the specified pattern and the date time * constants for the default locale. * * @param pattern * string pattern specification */ protected DateTimeFormat(String pattern) { this(pattern, getDefaultDateTimeFormatInfo()); } /** * Constructs a format object using the specified pattern and user-supplied * date time constants. * * @param pattern * string pattern specification * @param dtfi * DateTimeFormatInfo instance to use */ protected DateTimeFormat(String pattern, DateTimeFormatInfo dtfi) { super(pattern, dtfi); } }