java-time

问题 Most of the time, these 2 methods are each others inverse: Temporal Temporal.plus(long, TemporalUnit) long Temporal.until(Temporal, TemporalUnit) For example starting from 1-JAN: System.out.println("1-JAN plus 1 month: " + LocalDate.of(2017, 1, 1).plus(1, ChronoUnit.MONTHS)); System.out.println("1-JAN until 1-FEB in months: " + LocalDate.of(2017, 1, 1).until(LocalDate.of(2017, 2, 1), ChronoUnit.MONTHS)); They are each others inverse: 1-JAN plus 1 month: 2017-02-01 1-JAN until 1-FEB in months:

问题 I want to store time slot in the arraylist. i have start time and end time. based on start time it should create time slot. For example if start time is 09:00AM and end time is 21:00PM then it should add into arraylist like below 09:00AM 10:00AM 11:00AM 12:00PM 13:00PM 14:00PM ..... so on 21:00PM so one user books 13:00PM to 15:00PM slots so it should not be available to another user and other slot should be available. how to compare already booking time with new array list. Code private void

问题 I am looking at the DateTimeFormatter class and I was wondering where are the constants like "M" , "EEE" and "YY" etc are defined. More specifically there should be code like this somewhere given a ChronoField and TextStyle, it should return the DateTimeFormatter string snippet e.g. (ChronoField.MONTH_OF_YEAR, TextStyle.SHORT) should map to the string "MMM" 回答1: After some source digging, I found out that these are pre-defined in a private static final Map , called FIELD_MAP , which is a

问题 I am looking at the DateTimeFormatter class and I was wondering where are the constants like "M" , "EEE" and "YY" etc are defined. More specifically there should be code like this somewhere given a ChronoField and TextStyle, it should return the DateTimeFormatter string snippet e.g. (ChronoField.MONTH_OF_YEAR, TextStyle.SHORT) should map to the string "MMM" 回答1: After some source digging, I found out that these are pre-defined in a private static final Map , called FIELD_MAP , which is a

问题 Consider a code: TemporalAccessor date = DateTimeFormatter.ofPattern("yyyy-MM-dd").parse("9999-12-31"); Instant.from(date); The last line throws an exception: Unable to obtain Instant from TemporalAccessor: {},ISO resolved to 9999-12-31 of type java.time.format.Parsed How to create Instant from yyyy-MM-dd pattern? 回答1: The string "9999-12-31" only contains information about a date. It does not contain any information about the time-of-day or offset. As such, there is insufficient information

问题 This question already has answers here : cannot resolve symbol 'java.time.LocalDate' error in android studio (3 answers) Closed 2 years ago . I am facing with a ClassNotFoundException when I deploy my android application on my android phone. I tried on android phone which has Android 6.0.1 and Android 7.1.1 Whereas when I deploy the same application on an emulator which is (Nexus 5X API 26) and runs Android 8.0 I don't face any problem. The app loads smoothly. Build.gradle (app) file has

问题 I want to use java.time.LocalDate and java.time.LocalDateTime with an implicit Ordered like: val date1 = java.time.LocalDate.of(2000, 1, 1) val date2 = java.time.LocalDate.of(2010, 10, 10) if (date1 < date2) ... import scala.math.Ordering.Implicits._ doesn't work, because LocalDate inherits from Comparable<ChronoLocalDate> instead of Comparable<LocalDate> . How can I write my own imlicit Orderd to use <, <=, >, >= operators/methods to compare LocalDate 's? Edit: I found a way with use of an

问题 I want to use java.time.LocalDate and java.time.LocalDateTime with an implicit Ordered like: val date1 = java.time.LocalDate.of(2000, 1, 1) val date2 = java.time.LocalDate.of(2010, 10, 10) if (date1 < date2) ... import scala.math.Ordering.Implicits._ doesn't work, because LocalDate inherits from Comparable<ChronoLocalDate> instead of Comparable<LocalDate> . How can I write my own imlicit Orderd to use <, <=, >, >= operators/methods to compare LocalDate 's? Edit: I found a way with use of an

问题 java.time has an Instant class which encapsulates a position (or 'moment') on the timeline. While I understand that this is a seconds/nanoseconds value so not directly related to time zones or times offsets, its toString returns a date and time formatted as a UTC date/time, eg 2014-05-13T20:05:08.556Z. Also anInstant.atZone(zone) and anInstant.atOffset(offset) both produce a value that is consistent with treating the Instant as having an implied UTC time-zone/'zero' offset. I would have

问题 I updated to the latest Android N sdk. The only thing I don't understand is why I cannot import java.time into my code? I thought Java8 is available through Android N. Then why didn't Google add java.time package? 回答1: Android N is not supporting all the features of Java 8. Following features are only supported: Default and static interface methods Lambda expressions Repeatable annotations Reflection and language-related APIs: java.lang.FunctionalInterface java.lang.annotation.Repeatable java