rspec/rules/S2143/java/rule.adoc

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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|===
|Class|Use for

|LocalDate|a date, without time of day, offset, or zone
|LocalTime|the time of day, without date, offset, or zone
|LocalDateTime|the date and time, without offset, or zone
|OffsetDate|a date with an offset such as +02:00, without time of day, or zone
|OffsetTime|the time of day with an offset such as +02:00, without date, or zone
|OffsetDateTime|the date and time with an offset such as +02:00, without a zone
|ZonedDateTime|the date and time with a time zone and offset
|YearMonth|a year and month
|MonthDay|month and day
|Year/MonthOfDay/DayOfWeek/...|classes for the important fields
|DateTimeFields|stores a map of field-value pairs which may be invalid
|Calendrical|access to the low-level API
|Period|a descriptive amount of time, such as "2 months and 3 days"
|===

== Noncompliant Code Example

----
Date now = new Date();  // Noncompliant
DateFormat df = new SimpleDateFormat("dd.MM.yyyy");
Calendar christmas  = Calendar.getInstance();  // Noncompliant
christmas.setTime(df.parse("25.12.2020"));
----


== Compliant Solution

----
LocalDate now = LocalDate.now();  // gets calendar date. no time component
LocalTime now2 = LocalTime.now(); // gets current time. no date component
LocalDate christmas = LocalDate.of(2020,12,25);
----


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== Comments And Links
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