16f6c0aecf
Inline adoc files when they are included exactly once. Also fix language tags because this inlining gives us better information on what language the code is written in.
71 lines
2.2 KiB
Plaintext
71 lines
2.2 KiB
Plaintext
== Why is this an issue?
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The old, much-derided ``++Date++`` and ``++Calendar++`` classes have always been confusing and difficult to use properly, particularly in a multi-threaded context. ``++JodaTime++`` has long been a popular alternative, but now an even better option is built-in. Java 8's JSR 310 implementation offers specific classes for:
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[frame=all]
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[cols="^1,^1"]
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|===
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|Class|Use for
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|LocalDate|a date, without time of day, offset, or zone
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|LocalTime|the time of day, without date, offset, or zone
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|LocalDateTime|the date and time, without offset, or zone
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|OffsetDate|a date with an offset such as +02:00, without time of day, or zone
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|OffsetTime|the time of day with an offset such as +02:00, without date, or zone
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|OffsetDateTime|the date and time with an offset such as +02:00, without a zone
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|ZonedDateTime|the date and time with a time zone and offset
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|YearMonth|a year and month
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|MonthDay|month and day
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|Year/MonthOfDay/DayOfWeek/...|classes for the important fields
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|DateTimeFields|stores a map of field-value pairs which may be invalid
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|Calendrical|access to the low-level API
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|Period|a descriptive amount of time, such as "2 months and 3 days"
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|===
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=== Noncompliant code example
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[source,java]
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----
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Date now = new Date(); // Noncompliant
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DateFormat df = new SimpleDateFormat("dd.MM.yyyy");
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Calendar christmas = Calendar.getInstance(); // Noncompliant
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christmas.setTime(df.parse("25.12.2020"));
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----
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=== Compliant solution
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[source,java]
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----
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LocalDate now = LocalDate.now(); // gets calendar date. no time component
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LocalTime now2 = LocalTime.now(); // gets current time. no date component
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LocalDate christmas = LocalDate.of(2020,12,25);
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----
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ifdef::env-github,rspecator-view[]
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'''
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== Implementation Specification
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(visible only on this page)
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=== Message
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Use the Java 8 Date and Time API instead.
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'''
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== Comments And Links
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(visible only on this page)
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=== on 12 Oct 2014, 21:55:53 Ann Campbell wrote:
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\[~freddy.mallet] & [~nicolas.peru] I'm not wild about the title. Suggestions welcome!
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=== on 13 Oct 2014, 12:56:46 Nicolas Peru wrote:
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\[~ann.campbell.2] What about : classes from "java.time" package should be used for date and time. ?
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=== on 14 Oct 2014, 14:17:56 Ann Campbell wrote:
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Thanks [~nicolas.peru]. Updated.
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endif::env-github,rspecator-view[]
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