Re: Save user data where?

From:
Knute Johnson <nospam@rabbitbrush.frazmtn.com>
Newsgroups:
comp.lang.java.programmer
Date:
Wed, 18 Apr 2007 15:31:44 -0700
Message-ID:
<k%wVh.527210$BK1.301405@newsfe13.lga>
Thomas Fritsch wrote:

Karsten Wutzke schrieb:

I wish to save some user data (editable via GUI) on a per user basis.

Is there any nice mechanism in Java that puts such info into an
appropriate place? If I have to do that manually, what would be a nice
place to save some small files with bothering the user? Or shall I
force every user to specify a directory?


Sounds like you need java.util.prefs.Preferences.

You can get a handle to the user's preferences by:
  Preferences prefs =
     Preferences.userNodeForPackage(my.package.Main.class);
Java keeps the user's preferences in a platform-specific place:
 (*) for Windows: in a certain user-specific branch of the registry
 (*) for Unix/Linux: in a certain hidden file in the user's home dir.
But you don't have to care about those details.

You read/write specific key/value like this:
  String value = prefs.get(key);
  prefs.get(key, value);

For more details see the API docs
<http://java.sun.com/j2se/1.5.0/docs/api/java/util/prefs/Preferences.html>
<http://java.sun.com/j2se/1.5.0/docs/api/java/util/prefs/Preferences.html#userNodeForPackage(java.lang.Class)>


I hadn't seen this before (where have I been?). Where does it store
stuff on a Linux system?

--

Knute Johnson
email s/nospam/knute/

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