Accessing an databases in concurrent threads

[jda]

>  > The problem I'm having is that if a database is in use and another
>>  request comes in, I have to get acces to that database to do a query
>>  (again, read only, so no locked cursor problems). However, if I try
>>  to open a databas that is in use of course an exception is generated.
>>  I wonder what the best solution is?
>>
>>  I have thought of:
>>
>>  1. polling any open socket threads and setting "myDatabase" of the
>>  new thread to the "myDatabase" of a thread using the same folderItem
>>
>>  2. using a try/catch block when trying to open the database, and if
>>  it's a "file is open" error trying again (for,say, 60 seconds) until
>>  I either open the database or it times out.
>>
>>  Any thoughts/suggestions?
>
>Each thread should keep own cursor.
>
>You need one semaphore for Valentina
>
>Each thread must concurrent for this semaphore/mutex
>

Each thread does this already.

The problem isn't keeping the threads separate. The problem is that 
if one thread tries to open a database in use by another, there is an 
exception.

Jon