Hi all!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 anappropriate place? If I have to do that manually, what would be a niceplace to save some small files with bothering the user? Or shall Iforce every user to specify a directory?Karsten

Karsten Wutzke wrote:> Hi all!> > 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?> > Karsten> Look at the system property user.home.-- Knute Johnsonemail s/nospam/knute/

On 18 Apr., 19:19, Knute Johnson <nos...@rabbitbrush.frazmtn.com>wrote:> Karsten Wutzke wrote:> > Hi all!>> > 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?>> > Karsten>> Look at the system property user.home.>> -->> Knute Johnson> email s/nospam/knute/I know this. But I don't want to create files or directories "unasked"which will clutter the user's home dir and make some users really mad(as I would be).Karsten

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)>

-- 
Thomas

On Apr 18, 1:36 pm, Thomas Fritsch <i.dont.like.s...@invalid.com>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.h...)>>> --> ThomasThere wouldn't be any problem with permissions using this method,would there?  (AKA - The user can't write to the registry.)

On Apr 18, 2:36 pm, Jason Cavett <jason.cav...@gmail.com> wrote:> On Apr 18, 1:36 pm, Thomas Fritsch <i.dont.like.s...@invalid.com> wrote:> > 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.h...)>>> There wouldn't be any problem with permissions using this method,> would there?  (AKA - The user can't write to the registry.)The default Sun implementation on Windows stores preferences in a nodeunder HKEY_CURRENT_USER, which is always writable by the current userand is normally made part of the user's profile, whether local orroaming.So no, not really.

Karsten Wutzke wrote:> On 18 Apr., 19:19, Knute Johnson <nos...@rabbitbrush.frazmtn.com>> wrote:>> Karsten Wutzke wrote:>>> Hi all!>>> 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?>>> Karsten>> Look at the system property user.home.>>>> -->>>> Knute Johnson>> email s/nospam/knute/> > I know this. But I don't want to create files or directories "unasked"> which will clutter the user's home dir and make some users really mad> (as I would be).> > Karsten> Then store it on a remote server.  I really don't think that makes any sense but it accomplishes what you want; a file but not on the users computer.When I look in my Windoze computer home directory I can find 25 folders of stuff that applications have put there.  That is where that kind of stuff belongs.  I didn't look at my Linux home directory but I know there is a lot of application data there too.-- Knute Johnsonemail s/nospam/knute/

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 Johnsonemail s/nospam/knute/

On Apr 18, 5:53 pm, angrybald...@gmail.com wrote:> On Apr 18, 2:36 pm, Jason Cavett <jason.cav...@gmail.com> wrote:>>>> > On Apr 18, 1:36 pm, Thomas Fritsch <i.dont.like.s...@invalid.com> wrote:> > > 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.h...)>>> > There wouldn't be any problem with permissions using this method,> > would there?  (AKA - The user can't write to the registry.)>> The default Sun implementation on Windows stores preferences in a node> under HKEY_CURRENT_USER, which is always writable by the current user> and is normally made part of the user's profile, whether local or> roaming.>> So no, not really.By "normally" do you mean that, assuming no problems, I can assume thesettings will be saved on a per-user basis?

Knute Johnson wrote:> Thomas Fritsch wrote:>> >>   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.> > I hadn't seen this before (where have I been?).  Where does it store > stuff on a Linux system?> On my Linux I found it in file  $HOME/.java/.userprefs/my/package/prefs.xmlAnd (by the way) on Windows it is in registry section  HKEY_CURRENT_USER\Software\JavaSoft\prefs\my\package-- Thomas

Thomas Fritsch wrote:> On my Linux I found it in file>   $HOME/.java/.userprefs/my/package/prefs.xml     $HOME/.java/.userPrefs/my/package/prefs.xml> > And (by the way) on Windows it is in registry section>   HKEY_CURRENT_USER\Software\JavaSoft\prefs\my\package     HKEY_CURRENT_USER\Software\JavaSoft\Prefs\my\packageSorry for the 2 typos...-- Thomas

Thomas Fritsch wrote:> Thomas Fritsch wrote:>> On my Linux I found it in file>>   $HOME/.java/.userprefs/my/package/prefs.xml>     $HOME/.java/.userPrefs/my/package/prefs.xml>>>> And (by the way) on Windows it is in registry section>>   HKEY_CURRENT_USER\Software\JavaSoft\prefs\my\package>     HKEY_CURRENT_USER\Software\JavaSoft\Prefs\my\package> > Sorry for the 2 typos...> Thanks Thomas.-- Knute Johnsonemail s/nospam/knute/

Jason Cavett wrote:> On Apr 18, 5:53 pm, angrybald...@gmail.com wrote:>> On Apr 18, 2:36 pm, Jason Cavett <jason.cav...@gmail.com> wrote:>>>>>>>>> On Apr 18, 1:36 pm, Thomas Fritsch <i.dont.like.s...@invalid.com> wrote:>>>> 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.h...)>>>> There wouldn't be any problem with permissions using this method,>>> would there?  (AKA - The user can't write to the registry.)>> The default Sun implementation on Windows stores preferences in a node>> under HKEY_CURRENT_USER, which is always writable by the current user>> and is normally made part of the user's profile, whether local or>> roaming.>>>> So no, not really.> > By "normally" do you mean that, assuming no problems, I can assume the> settings will be saved on a per-user basis?> Yes because for one thing the registry hive where the data is accessible for the current user is HKEY_CURRENT_USER (imagine that) so it would have to be on a per user basis because there is only one current user allowed with Windows XP. Plus, if you look into HKEY_USERS hive in the registry it will list all the SIDs of the users who have logged into the PC whose registry you are currently viewing. A user's registry data is part of the users profile so it will follow them (stored in ntuser.dat in every user's profile) and when they log in the HKEY_CURRENT_USER hive is just a link to the real location under HKEY_USERS.  It is possible for permissions to be screwed up on HKEY_CURRENT_USER such that a user can't retain settings (like Windows Explorer folder view preferences) but normally each user can read/write to that location because they need to.I use the Preferences API in my program to store connection settings to a remote server in the registry for each other based on a recommendation I received from this group a few months ago. The API is so easy and after I experimented with it I was able to implement my code very quickly.

On Apr 19, 8:36 pm, Brandon McCombs <n...@none.com> wrote:
> Jason Cavett wrote:
> > On Apr 18, 5:53 pm, angrybald...@gmail.com wrote:
> >> On Apr 18, 2:36 pm, Jason Cavett <jason.cav...@gmail.com> wrote:
>
> >>> On Apr 18, 1:36 pm, Thomas Fritsch <i.dont.like.s...@invalid.com> wrote:
> >>>> 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.h...)>
> >>> There wouldn't be any problem with permissions using this method,
> >>> would there?  (AKA - The user can't write to the registry.)
> >> The default Sun implementation on Windows stores preferences in a node
> >> under HKEY_CURRENT_USER, which is always writable by the current user
> >> and is normally made part of the user's profile, whether local or
> >> roaming.
>
> >> So no, not really.
>
> > By "normally" do you mean that, assuming no problems, I can assume the
> > settings will be saved on a per-user basis?
>
> Yes because for one thing the registry hive where the data is accessible
> for the current user is HKEY_CURRENT_USER (imagine that) so it would
> have to be on a per user basis because there is only one current user
> allowed with Windows XP. Plus, if you look into HKEY_USERS hive in the
> registry it will list all the SIDs of the users who have logged into the
> PC whose registry you are currently viewing. A user's registry data is
> part of the users profile so it will follow them (stored in ntuser.dat
> in every user's profile) and when they log in the HKEY_CURRENT_USER hive
> is just a link to the real location under HKEY_USERS.  It is possible
> for permissions to be screwed up on HKEY_CURRENT_USER such that a user
> can't retain settings (like Windows Explorer folder view preferences)
> but normally each user can read/write to that location because they need
> to.
>
> I use the Preferences API in my program to store connection settings to
> a remote server in the registry for each other based on a recommendation
> I received from this group a few months ago. The API is so easy and
> after I experimented with it I was able to implement my code very quickly.- Hide quoted text -
>
> - Show quoted text -

I just finished implementing Preferences for an application I'm
working on.  Wow...haha...that was so painless I felt like I did
something wrong.

;-)  Loving the Preferences.