如何创建某个日期的文本表示，考虑区域设置并且仅包含日期和月份（无年份）？
以下代码为我提供了类似 23/09/2010
的内容DateFormat.getDateInstance(DateFormat.SHORT, Locale.getDefault()).format(date);
我想 23/09
答案 0 :(得分：43)
这适用于 Android ，以防有人需要它：
int flags = DateUtils.FORMAT_SHOW_DATE | DateUtils.FORMAT_NO_YEAR;
String monthAndDayText = DateUtils.formatDateTime(context, date, flags);
答案 1 :(得分：23)
您可以使用正则表达式修剪所有y以及之前和之后的任何非字母字符（如果有）。这是一个启动示例：
public static void main(String[] args) throws Exception {
for (Locale locale : Locale.getAvailableLocales()) {
DateFormat df = getShortDateInstanceWithoutYears(locale);
System.out.println(locale + ": " + df.format(new Date()));
}
}
public static DateFormat getShortDateInstanceWithoutYears(Locale locale) {
SimpleDateFormat sdf = (SimpleDateFormat) DateFormat.getDateInstance(DateFormat.SHORT, locale);
sdf.applyPattern(sdf.toPattern().replaceAll("[^\\p{Alpha}]*y+[^\\p{Alpha}]*", ""));
return sdf;
}
您会看到此代码段也会针对所有区域设置对其进行测试。它看起来适用于所有语言环境。
答案 2 :(得分：8)
只想在模式中提供另一个修改删除年份，这适用于DateFormat.MEDIUM，即使在诸如pt_PT（d'de'MMM'de'yyyy）或lv_LV（y。'gada'd。 MMM）。
public static DateFormat getMediumDateInstanceWithoutYears()
{
SimpleDateFormat sdf = (SimpleDateFormat) DateFormat.getDateInstance(DateFormat.MEDIUM);
sdf.applyPattern(sdf.toPattern().replaceAll(
"([^\\p{Alpha}']|('[\\p{Alpha}]+'))*y+([^\\p{Alpha}']|('[\\p{Alpha}]+'))*",
""));
return sdf;
}
答案 3 :(得分：4)
我是这样做的：
DateFormat dateFormat = DateFormat.getDateInstance(DateFormat.SHORT, Locale.getDefault());
if (dateFormat instanceof SimpleDateFormat) {
SimpleDateFormat simpleDateFormat = (SimpleDateFormat) dateFormat;
String pattern = simpleDateFormat.toPattern();
// I modified the pattern here so that dd.MM.yyyy would result to dd.MM
simpleDateFormat.applyPattern(modifiedPattern);
... etc
}
答案 4 :(得分：4)
以下是一个实用工具类，它为您提供不带年份的日期格式。我使用以下代码列出了Java已知的所有日期格式。
Locale[] locales = SimpleDateFormat.getAvailableLocales();
for (int i = 0; i < locales.length; i++) {
Locale locale = locales[i];
DateFormat dateFormat = DateFormat.getDateInstance(DateFormat.FULL, locale);
}
然后手动删除年份部分。它返回两种日期格式，正常和缩写，即3月18日星期一与3月18日星期一。
public class DateFormatWithoutYear {
private static Map<String, String> formats = new HashMap<String, String>();
private static String DEFAULT_FORMAT = "EEEE, d MMMM";
static {
formats.put("_af", "EEEE dd MMMM");
formats.put("_am", "EEEE, d MMMM");
formats.put("_az", "EEEE, d, MMMM");
formats.put("_be", "EEEE, d MMMM");
formats.put("_bg", "dd MMMM, EEEE");
formats.put("BG_bg", "dd MMMM, EEEE");
formats.put("_ca", "EEEE d MMMM");
formats.put("ES_ca", "EEEE d MMMM");
formats.put("_cs", "EEEE, d. MMMM");
formats.put("CZ_cs", "EEEE, d. MMMM");
formats.put("_da", "EEEE 'den' d. MMMM");
formats.put("DK_da", "EEEE 'den' d. MMMM");
formats.put("_de", "EEEE, d. MMMM");
formats.put("AT_de", "EEEE, dd. MMMM");
formats.put("BE_de", "EEEE, d. MMMM");
formats.put("CH_de", "EEEE, d. MMMM");
formats.put("DE_de", "EEEE, d. MMMM");
formats.put("LI_de", "EEEE, d. MMMM");
formats.put("LU_de", "EEEE, d. MMMM");
formats.put("_el", "EEEE, d MMMM");
formats.put("GR_el", "EEEE, d MMMM");
formats.put("_en", "EEEE, MMMM d");
formats.put("AU_en", "EEEE, d MMMM");
formats.put("BE_en", "EEEE d MMMM");
formats.put("BW_en", "EEEE dd MMMM");
formats.put("BZ_en", "EEEE, MMMM d");
formats.put("CA_en", "EEEE, d MMMM");
formats.put("GB_en", "EEEE, d MMMM");
formats.put("HK_en", "EEEE, d MMMM");
formats.put("IE_en", "EEEE d MMMM");
formats.put("IN_en", "EEEE d MMMM");
formats.put("JM_en", "EEEE, MMMM d");
formats.put("MH_en", "EEEE, MMMM d");
formats.put("MT_en", "EEEE, d MMMM");
formats.put("NA_en", "EEEE, MMMM d");
formats.put("NZ_en", "EEEE, d MMMM");
formats.put("PH_en", "EEEE, MMMM d");
formats.put("PK_en", "EEEE, MMMM d");
formats.put("RH_en", "EEEE dd MMMM");
formats.put("SG_en", "EEEE, d MMMM");
formats.put("TT_en", "EEEE, MMMM d");
formats.put("US_en", "EEEE, MMMM d");
formats.put("VI_en", "EEEE, MMMM d");
formats.put("ZA_en", "EEEE dd MMMM");
formats.put("ZW_en", "EEEE dd MMMM");
formats.put("_es", "EEEE d 'de' MMMM");
formats.put("AR_es", "EEEE d 'de' MMMM");
formats.put("BO_es", "EEEE d 'de' MMMM");
formats.put("CL_es", "EEEE d 'de' MMMM");
formats.put("CO_es", "EEEE d 'de' MMMM");
formats.put("CR_es", "EEEE d 'de' MMMM");
formats.put("DO_es", "EEEE d 'de' MMMM");
formats.put("EC_es", "EEEE d 'de' MMMM");
formats.put("ES_es", "EEEE d 'de' MMMM");
formats.put("GT_es", "EEEE d 'de' MMMM");
formats.put("HN_es", "EEEE dd 'de' MMMM");
formats.put("MX_es", "EEEE d 'de' MMMM");
formats.put("NI_es", "EEEE d 'de' MMMM");
formats.put("PA_es", "EEEE d 'de' MMMM");
formats.put("PE_es", "EEEE d 'de' MMMM");
formats.put("PR_es", "EEEE d 'de' MMMM");
formats.put("PY_es", "EEEE d 'de' MMMM");
formats.put("SV_es", "EEEE d 'de' MMMM");
formats.put("US_es", "EEEE d 'de' MMMM");
formats.put("UY_es", "EEEE d 'de' MMMM");
formats.put("VE_es", "EEEE d 'de' MMMM");
formats.put("_et", "EEEE, d. MMMM");
formats.put("_eu", "EEEE, MMMM'ren' dd'a'");
formats.put("_fi", "cccc, d. MMMM");
formats.put("FI_fi", "cccc, d. MMMM");
formats.put("_fil", "EEEE, MMMM dd");
formats.put("PH_fil", "EEEE, MMMM dd");
formats.put("_fr", "EEEE d MMMM");
formats.put("BE_fr", "EEEE d MMMM");
formats.put("CA_fr", "EEEE d MMMM");
formats.put("CH_fr", "EEEE, d MMMM");
formats.put("FR_fr", "EEEE d MMMM");
formats.put("LU_fr", "EEEE d MMMM");
formats.put("MC_fr", "EEEE d MMMM");
formats.put("_gl", "EEEE dd MMMM");
formats.put("_iw", "EEEE, d בMMMM");
formats.put("IL_iw", "EEEE, d בMMMM");
formats.put("_hi", "EEEE, d MMMM");
formats.put("IN_hi", "EEEE, d MMMM");
formats.put("_hr", "EEEE, d. MMMM");
formats.put("HR_hr", "EEEE, d. MMMM");
formats.put("_hu", "MMMM d., EEEE");
formats.put("HU_hu", "MMMM d., EEEE");
formats.put("_hy", "EEEE, MMMM d");
formats.put("_in", "EEEE, dd MMMM");
formats.put("ID_in", "EEEE, dd MMMM");
formats.put("_it", "EEEE d MMMM");
formats.put("CH_it", "EEEE, d MMMM");
formats.put("IT_it", "EEEE d MMMM");
formats.put("_ja", "M月d日EEEE");
formats.put("JP_ja", "M月d日EEEE");
formats.put("_ka", "EEEE, MMMM dd");
formats.put("_kk", "EEEE, d MMMM");
formats.put("_ko", "M월 d일 EEEE");
formats.put("KR_ko", "M월 d일 EEEE");
formats.put("_lt", "'m'. MMMM d 'd'., EEEE");
formats.put("LT_lt", "'m'. MMMM d 'd'., EEEE");
formats.put("_lv", "EEEE, d. MMMM");
formats.put("LV_lv", "EEEE, d. MMMM");
formats.put("_mk", "EEEE, dd MMMM");
formats.put("_ms", "EEEE, d MMMM");
formats.put("_nb", "EEEE d. MMMM");
formats.put("NO_nb", "EEEE d. MMMM");
formats.put("_nl", "EEEE d MMMM");
formats.put("BE_nl", "EEEE d MMMM");
formats.put("NL_nl", "EEEE d MMMM");
formats.put("_pl", "EEEE, d MMMM");
formats.put("PL_pl", "EEEE, d MMMM");
formats.put("_ps", "EEEE د MMMM d");
formats.put("_pt", "EEEE, d 'de' MMMM");
formats.put("BR_pt", "EEEE, d 'de' MMMM");
formats.put("PT_pt", "EEEE, d 'de' MMMM");
formats.put("_rm", "EEEE, d. MMMM");
formats.put("_ro", "EEEE, d MMMM");
formats.put("RO_ro", "EEEE, d MMMM");
formats.put("_ru", "EEEE, d MMMM");
formats.put("RU_ru", "EEEE, d MMMM");
formats.put("UA_ru", "EEEE, d MMMM");
formats.put("_sk", "EEEE, d. MMMM");
formats.put("SK_sk", "EEEE, d. MMMM");
formats.put("_sl", "EEEE, dd. MMMM");
formats.put("SI_sl", "EEEE, dd. MMMM");
formats.put("_sr", "EEEE, dd. MMMM");
formats.put("BA_sr", "EEEE, dd. MMMM");
formats.put("CS_sr", "EEEE, dd. MMMM");
formats.put("CYRL_sr", "EEEE, dd. MMMM");
formats.put("CYRL_sr", "EEEE, dd. MMMM");
formats.put("CYRL_sr", "EEEE, dd. MMMM");
formats.put("CYRL_sr", "EEEE, dd. MMMM");
formats.put("CYRL_sr", "EEEE, dd. MMMM");
formats.put("CYRL_sr", "EEEE, dd. MMMM");
formats.put("LATN_sr", "EEEE, dd. MMMM");
formats.put("LATN_sr", "EEEE, dd. MMMM");
formats.put("LATN_sr", "EEEE, dd. MMMM");
formats.put("LATN_sr", "EEEE, dd. MMMM");
formats.put("LATN_sr", "EEEE, dd. MMMM");
formats.put("LATN_sr", "EEEE, dd. MMMM");
formats.put("ME_sr", "EEEE, dd. MMMM");
formats.put("RS_sr", "EEEE, dd. MMMM");
formats.put("YU_sr", "EEEE, dd. MMMM");
formats.put("_sv", "EEEE'en' 'den' d:'e' MMMM");
formats.put("FI_sv", "EEEE'en' 'den' d:'e' MMMM");
formats.put("SE_sv", "EEEE'en' 'den' d:'e' MMMM");
formats.put("_sw", "EEEE, d MMMM");
formats.put("_th", "EEEEที่ d MMMM G");
formats.put("TH_th", "EEEEที่ d MMMM G");
formats.put("_tr", "d MMMM EEEE");
formats.put("TR_tr", "d MMMM EEEE");
formats.put("_uk", "EEEE, d MMMM");
formats.put("UA_uk", "EEEE, d MMMM");
formats.put("_uz", "EEEE, MMMM dd");
formats.put("_vi", "EEEE, 'ngày' dd MMMM");
formats.put("VN_vi", "EEEE, 'ngày' dd MMMM");
formats.put("_zh", "M月d日EEEE");
formats.put("CN_zh", "M月d日EEEE");
formats.put("HK_zh", "M月d日EEEE");
formats.put("HANS_zh", "M月d日EEEE");
formats.put("HANS_zh", "M月d日EEEE");
formats.put("HANS_zh", "M月d日EEEE");
formats.put("HANS_zh", "M月d日EEEE");
formats.put("HANT_zh", "M月d日EEEE");
formats.put("HANT_zh", "M月d日EEEE");
formats.put("HANT_zh", "MM月dd日EEEE");
formats.put("HANT_zh", "M月d日EEEE");
formats.put("MO_zh", "MM月dd日EEEE");
formats.put("SG_zh", "M月d日EEEE");
formats.put("TW_zh", "M月d日EEEE");
formats.put("_zu", "EEEE dd MMMM");
}
public static String getLongFormatWithoutYear(Locale locale) {
if (locale != null) {
String key = locale.getCountry() + "_" + locale.getLanguage();
String format = formats.get(key);
if (format != null) {
return format;
}
}
return DEFAULT_FORMAT;
}
public static String getShortFormatWithoutYear(Locale locale) {
String longFormat = getLongFormatWithoutYear(locale);
return longFormat.replaceAll("E+", "E").replaceAll("MMMM", "MMM");
}
}
答案 5 :(得分：3)
这里的主要困难是在某些区域设置中，月份和日期的顺序不同。我解决它的方式与此处提供的方式不同，并希望它适用于所有情况。
Date dateObject = ...;
String dayMonthDateString = getDayMonthDateString(dateObject, Locale.GERMANY);
Log.i("customDate", "dayMonthDateString = " + dayMonthDateString);
private String getDayMonthDateString(Date date, Locale locale)
{
try
{
boolean dayBeforeMonth = defineDayMonthOrder(locale);
SimpleDateFormat newDateFormat;
if (dayBeforeMonth)
{
newDateFormat = new SimpleDateFormat("dd/MM", locale);
}
else
{
newDateFormat = new SimpleDateFormat("MM/dd", locale);
}
return newDateFormat.format(date);
}
catch (ParseException e)
{
e.printStackTrace();
}
return null;
}
private boolean defineDayMonthOrder(Locale locale) throws ParseException
{
String day = "10";
String month = "11";
String year = "12";
String calendarDate = day + "." + month + "." + year;
SimpleDateFormat format = new SimpleDateFormat("dd.MM.yy");
Date date = format.parse(calendarDate);
String localizedDate = SimpleDateFormat.getDateInstance(SimpleDateFormat.SHORT, locale).format(date);
int indexOfDay = localizedDate.indexOf(day);
int indexOfMonth = localizedDate.indexOf(month);
return indexOfDay < indexOfMonth;
}
答案 6 :(得分：1)
使用com.ibm.icu库：
import com.ibm.icu.text.DateFormat;
DateFormat.getPatternInstance(DateFormat.MONTH_DAY, locale).format(date);
答案 7 :(得分：1)
如果您使用Android，则可以使用getBestDateTimePattern，并将所有要包含的字段放在那里。它应该根据当前的语言环境自动输入正确的顺序和特殊字符。
可悲的是，它需要API 18+。
编辑：遗憾的是，这似乎是一个不太好的选择。我在这里写过： http://code.google.com/p/android/issues/detail?id=171591所以，这就是我所做的：
public static String convertDateToString(Context context, Locale locale, final Date date, boolean alsoShowYearIfPossible) {
if (date == null)
return "";
String defaultDateFormat;
if (locale != null) {
defaultDateFormat = ((SimpleDateFormat) DateFormat.getDateInstance(DateFormat.SHORT, locale)).toLocalizedPattern();
} else defaultDateFormat = getDefaultDateFormat(context);
if (alsoShowYearIfPossible)
return new SimpleDateFormat(defaultDateFormat, Locale.getDefault()).format(date);
//need removal of year
String removedYearFormat = defaultDateFormat.replaceAll("[^{mdMD}]*y+[^{mdMD}]*", "");
String result = new SimpleDateFormat(removedYearFormat, Locale.getDefault()).format(date);
//Log.d("AppLog", locale + ": \"" + defaultDateFormat + "\" => \"" + removedYearFormat + "\" =>" + result);
return result;
}
private static String getDefaultDateFormat(final Context context) {
String dateFormatString = Settings.System.getString(context.getContentResolver(), Settings.System.DATE_FORMAT);
if (TextUtils.isEmpty(dateFormatString)) {
// if device date format is available , use device date order,and if not available ,use default
final char[] dateFormatOrder = android.text.format.DateFormat.getDateFormatOrder(context);
if (dateFormatOrder.length == 0)
dateFormatString = DEFAULT_DATE_FORMAT;
else {
// construct the date format based on the device date order
final StringBuilder sb = new StringBuilder();
for (int i = 0; i < dateFormatOrder.length; ++i) {
final char c = dateFormatOrder[i];
switch (Character.toLowerCase(c)) {
case 'y':
sb.append("yyyy");
break;
case 'm':
sb.append("MM");
break;
case 'd':
sb.append("dd");
break;
}
if (i != dateFormatOrder.length - 1)
sb.append('-');
}
dateFormatString = sb.toString();
}
}
return dateFormatString;
}
此代码适用于Android 5.0.2上可用的任何区域设置。
以下是如何在区域设置上进行检查的示例：
Date date = new Date();
for (Locale locale : Locale.getAvailableLocales()) {
SimpleDateFormat sdf = (SimpleDateFormat) DateFormat.getDateInstance(DateFormat.SHORT, locale);
String localizedDatePattern = sdf.toLocalizedPattern();
convertDateToString(this,locale,date,false);
}
答案 8 :(得分：1)
虽然Andrzej Pronobis的答案非常好，但是对于ZH本地而言它并不起作用。我最终手动从本地化模式中删除了一年。此功能已针对SHORT，MEDIUM，LONG和FULL格式的所有本地人进行了测试。
public String removeYearFromPattern(String pattern) throws SCException {
int yPos = 0;
while (yPos < pattern.length() && pattern.charAt(yPos) != 'y' && pattern.charAt(yPos) != 'Y') {
if (pattern.charAt(yPos) == '\'') {
yPos++;
while (yPos < pattern.length() && pattern.charAt(yPos) != '\'') yPos++;
}
yPos++;
}
if (yPos >= pattern.length()) throw new IllegalArgumentException("Did not find year in pattern");
String validPatternLetters = "EMd";
// go forward
int endPos = yPos;
while (endPos < pattern.length() && validPatternLetters.indexOf(pattern.charAt(endPos)) == -1) {
endPos++;
if (endPos < pattern.length() && pattern.charAt(endPos) == '\'') {
endPos++;
while (endPos < pattern.length() && pattern.charAt(endPos) != '\'')
endPos++;
}
}
if (endPos != pattern.length()) validPatternLetters += ',';
// go backward
int startPos = yPos;
while (startPos >= 0 && validPatternLetters.indexOf(pattern.charAt(startPos)) == -1) {
startPos--;
if (startPos >= 0 && pattern.charAt(startPos) == '\'') {
startPos--;
while (startPos >= 0 && pattern.charAt(startPos) != '\'') startPos--;
}
}
startPos++;
String yLetters = pattern.substring(startPos, endPos);
return pattern.replace(yLetters, " ").trim();
}
上面的功能可以通过运行来测试：
for (Locale locale : Locale.getAvailableLocales()) {
SimpleDateFormat df = (SimpleDateFormat) DateFormat.getDateInstance(DateFormat.FULL, locale);
String dfPattern = "?";
String newPattern = "?";
try {
dfPattern = df.toPattern();
newPattern = removeYearFromPattern(dfPattern);
df.applyPattern(newPattern);
} catch (IllegalArgumentException e) {
Log.e(TAG, "Error removing year for " + locale + ": " + e.getMessage());
}
Log.d(TAG, locale + ": old " + dfPattern + "; new " + newPattern + "; result " + df.format(new Date()));
}
我知道它不像正则表达式那么优雅，但它更快一点，适用于所有当地人（如果我能够识别）。
答案 9 :(得分：-4)
或
SimpleDateFormat dateFormat = new SimpleDateFormat("EEE MMM d');
dateFormat.format(date);