I want to express periods in the day, such as in the morning, in the afternoon, or at night, not just AM or PM.
Is there any pattern in java.time API to format and parse periods in a day, such as in the morning, in the afternoon, or at night using DateTimeFormatter e.g.
final DateTimeFormatter FORMATTER = DateTimeFormatter
.ofPattern("<<pattern>>", Locale.ENGLISH);
// Expected output: in the morning
System.out.println(LocalTime.of(8, 20, 30).format(FORMATTER));
// Expected output: in the evening
System.out.println(LocalTime.of(20, 20, 30).format(FORMATTER));
Java 16 introduced a new formatter pattern symbol B and supporting methods in the DateTimeFormatter and DateTimeFormatterBuilder classes.
Here are the strings that you can parse or generate using this symbol, in English for United States:
midnightat nightin the morningnoonin the afternoonin the eveningLet’s see which hour falls into which of the six categories, using a pattern of "HH:mm B".
IntStream
.rangeClosed ( 0 , 23 ) // Generate a stream of integers 0 through 23.
.mapToObj ( LocalTime.MIN :: withHour ) // Returns a `LocalTime` object. Start with the time 00:00, then switch out the hour.
.map ( localTime -> localTime.format ( DateTimeFormatter.ofPattern ( "HH:mm B" ).withLocale ( Locale.of ( "en" , "US" ) ) ) ) // Generate text representing the value of each `LocalTime` object.
.forEach ( System.out :: println ); // Dump to console.
00:00 midnight
01:00 at night
02:00 at night
03:00 at night
04:00 at night
05:00 at night
06:00 in the morning
07:00 in the morning
08:00 in the morning
09:00 in the morning
10:00 in the morning
11:00 in the morning
12:00 noon
13:00 in the afternoon
14:00 in the afternoon
15:00 in the afternoon
16:00 in the afternoon
17:00 in the afternoon
18:00 in the evening
19:00 in the evening
20:00 in the evening
21:00 at night
22:00 at night
23:00 at night
Note: Do not forget to specify the applicable Locale because such texts are Locale-sensitive. Check Always specify a Locale with a date-time formatter for custom formats to learn more about the importance of specifying Locale while using a date-time formatting type.
Switch that Locale to French language with Canada cultural norms (Locale.of( "fr" , "CA" )).
00:00 minuit
01:00 du mat.
…
11:00 du mat.
12:00 midi
13:00 après-midi
…
17:00 après-midi
18:00 du soir
…
23:00 du soir
More example code:
Demo:
import java.time.LocalDateTime;
import java.time.LocalTime;
import java.time.ZoneId;
import java.time.ZonedDateTime;
import java.time.format.DateTimeFormatter;
import java.util.Locale;
class Main {
private static final DateTimeFormatter FORMATTER = DateTimeFormatter
.ofPattern("B", Locale.ENGLISH);
public static void main(String[] args) {
// Now in the default time zone
ZonedDateTime now = ZonedDateTime.now();
System.out.println(now);
System.out.println(now.format(FORMATTER));
// Now in America/New_York
ZonedDateTime nowInNy = ZonedDateTime.now(ZoneId.of("America/New_York"));
System.out.println(nowInNy);
System.out.println(nowInNy.format(FORMATTER));
// A fixed time in the evening
System.out.println(LocalTime.of(20, 20, 30).format(FORMATTER));
// A fixed time at night
System.out.println(LocalTime.of(23, 20, 30).format(FORMATTER));
// Parsing a date-time with period specified as 'in the afternoon'
String strDateTime = "22 Dec 2024 12:35:40 in the afternoon";
LocalDateTime ldt = LocalDateTime.parse(strDateTime,
DateTimeFormatter.ofPattern("dd MMM uuuu hh:mm:ss B", Locale.ENGLISH));
System.out.println(ldt);
}
}
A sample output when executed in the afternoon on a JVM set with Europe/London time zone:
2024-12-22T12:29:52.190717500Z[Europe/London]
in the afternoon
2024-12-22T07:29:52.220715700-05:00[America/New_York]
in the morning
in the evening
at night
2024-12-22T12:35:40
Some examples of parsing/formatting with non-English Locales:
import java.time.LocalTime;
import java.time.format.DateTimeFormatter;
import java.util.Locale;
import static java.lang.System.out;
class Main {
private static final DateTimeFormatter FORMATTER =
DateTimeFormatter.ofPattern("hh B");
public static void main(String[] args) {
// Examples of formatting a time in some non-English languages
// A time at night
LocalTime time = LocalTime.of(23, 20, 30);
// Some non-English locales
Locale localeFr = Locale.forLanguageTag("fr"); // French
Locale localeEs = Locale.forLanguageTag("es"); // Spanish
Locale localeDe = Locale.forLanguageTag("de"); // German
Locale localeHi = Locale.forLanguageTag("hi"); // Hindi
Locale localeBn = Locale.forLanguageTag("bn"); // Bangla
out.println(time.format(FORMATTER.localizedBy(localeFr))); // French
out.println(time.format(FORMATTER.localizedBy(localeEs))); // Spanish
out.println(time.format(FORMATTER.localizedBy(localeDe))); // German
out.println(time.format(FORMATTER.localizedBy(localeHi))); // Hindi
out.println(time.format(FORMATTER.localizedBy(localeBn))); // Bangla
// Examples of parsing date-time strings with period of the day
// specified in a non-English language
out.println(
LocalTime.parse("11h du soir", // French
DateTimeFormatter.ofPattern("hh'h' B")
.localizedBy(localeFr)));
out.println(
LocalTime.parse("11h35 du soir", // French
DateTimeFormatter.ofPattern("hh'h'mm B")
.localizedBy(localeFr)));
out.println(LocalTime.parse("11h de la noche", // Spanish
DateTimeFormatter.ofPattern("hh'h' B")
.localizedBy(localeEs)));
out.println(LocalTime.parse("11 abends", // German
FORMATTER.localizedBy(localeDe)));
out.println(LocalTime.parse("11:35 रात", // Hindi
DateTimeFormatter.ofPattern("hh:mm B")
.localizedBy(localeHi)));
out.println(LocalTime.parse("১১ রাত্রিবেলায়", // Bangla
FORMATTER.localizedBy(localeBn)));
}
}
Output:
11 du soir
11 de la noche
11 abends
11 रात
১১ রাত্রিবেলায়
23:00
23:35
23:00
23:00
23:35
23:00