I am writing an application. In that application I have an instance that I only want to happen the first time that the application is opened. I want to know how to write something in Java that will only make that instance happen that first time. Like a registration code or something like that.
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1Can't you maintain a simple boolean flag to keep track of that? – Bala R Apr 20 '11 at 02:26
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PersistentStore -- create a Singleton. The Blackberry dev forums have an excellent singleton approach that utilizes the RuntimeStore, but that does not cross restarts, PersistentStore does.
Dan
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"Item 3: Enforce the Singleton Property with a Private Constructor or an enum Type"—Joshua Bloch, Effective Java.
trashgod
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2PersistentStore -- create a Singleton. The Blackberry dev forums have an excellent singleton approach that utilizes the RuntimeStore, but that does not cross restarts, PersistentStore does. – Dan Apr 20 '11 at 02:45
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@Dan: Thanks for commenting on this. IIUC, [`PersistentStore`](http://www.blackberry.com/developers/docs/3.7api/net/rim/device/api/system/PersistentStore.html) is particularly apropos to the question. It might be worth making it a separate answer. – trashgod Apr 20 '11 at 03:00
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1thx trashgod, newb thing -- just spreading the luv an 4getting about status ;) – Dan Apr 20 '11 at 03:04
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i know nothing about blackberry, but this seems like it could be answered with a generic answer:
set a flag somewhere
mkoryak
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