问题
I am pretty new to Java 8 time, so this question probably has an obvious answer but after reading the other similar SO questions I couldn't spot any similarities which cause my issue.
Here's my class:
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.Locale;
public class LocalDateTimeIssue {
public static void main(String[] args) {
String dateTimeString = "18-04-2019 12:14:46";
DateTimeFormatter dtf = DateTimeFormatter.ofPattern("dd-MM-yyyy hh:mm:ss", Locale.US);
LocalDateTime ldt = LocalDateTime.parse(dateTimeString , dtf);
System.out.println(ldt.getSecond());
}
}
This throws the following exception:
Exception in thread "main" java.time.format.DateTimeParseException: Text '18-04-2019 12:14:46' could not be parsed: Unable to obtain LocalDateTime from TemporalAccessor: {MilliOfSecond=0, MinuteOfHour=14, HourOfAmPm=0, NanoOfSecond=0, MicroOfSecond=0, SecondOfMinute=46},ISO resolved to 2019-04-18 of type java.time.format.Parsed
at java.time.format.DateTimeFormatter.createError(DateTimeFormatter.java:1920)
at java.time.format.DateTimeFormatter.parse(DateTimeFormatter.java:1855)
at java.time.LocalDateTime.parse(LocalDateTime.java:492)
at LocalDateTimeIssue.main(LocalDateTimeIssue.java:10)
Caused by: java.time.DateTimeException: Unable to obtain LocalDateTime from TemporalAccessor: {MilliOfSecond=0, MinuteOfHour=14, HourOfAmPm=0, NanoOfSecond=0, MicroOfSecond=0, SecondOfMinute=46},ISO resolved to 2019-04-18 of type java.time.format.Parsed
at java.time.LocalDateTime.from(LocalDateTime.java:461)
at java.time.format.Parsed.query(Parsed.java:226)
at java.time.format.DateTimeFormatter.parse(DateTimeFormatter.java:1851)
... 2 more
Caused by: java.time.DateTimeException: Unable to obtain LocalTime from TemporalAccessor: {MilliOfSecond=0, MinuteOfHour=14, HourOfAmPm=0, NanoOfSecond=0, MicroOfSecond=0, SecondOfMinute=46},ISO resolved to 2019-04-18 of type java.time.format.Parsed
at java.time.LocalTime.from(LocalTime.java:409)
at java.time.LocalDateTime.from(LocalDateTime.java:457)
... 4 more
回答1:
It has to be dd-MM-yyyy HH:mm:ss
h clock-hour-of-am-pm (1-12) number 12
H hour-of-day (0-23) number 0
Because in your example, the 12 can either be AM or PM.
The formatter cannot decide between AM or PM as the information is missing:
a am-pm-of-day text PM
Both are possible, thus the error Unable to obtain LocalTime occurs.
来源：https://stackoverflow.com/questions/61250313/unable-to-obtain-localtime-from-temporalaccessor