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Originally published at Internet.comBusiness applications often require date and time calculations. Furthermore, in a global environment, these calculations must be localized for various geographical regions in which the application is running. The Java platform took a huge step in streamlining the way it deals with date and time by introducing the abstract java.util.Calendar class. Subclasses of Calendar interpret a date according to the rules of a specific calendar system. One such subclass is java.util.GregorianCalendar. You can use the methods and properties of GregorianCalendar for many of your date and time calculations and comparisons.
Piroz Mohseni
You have a few choices with the constructor. If you are happy with the default time zone and default locale object, then you can use the null constructor (no arguments) or one of the constructors that allows you to specify the year, month, date, hour, and minutes. For applications that could potentially be used in different regions, you probably want to be more specific about the Locale and TimeZone objects. There are constructors that allow you to specify a Locale, a TimeZone, or both to create the GregorianCalendar object. If you are going to use TimeZone, take a look at java.util.SimpleTimeZone, which is a concrete subclass of TimeZone. " The GreogorianCalendar class offers most of the information and calculations a typical date-based application needs." ...
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