JDBC implementation in an application ... newbie question

Hi all ...
My first post here. Hope Im at the right place.
I've just started out with java, had gotten the basics and started to develop a little. Now, I would like to involve a MySQL database. I have made a few small connection tests and selections/insertions and all works fine.
Now, I have been googleing the net a few times but I cant seem to find any good source of information on how you implement the DB layer in an application. How is it usually done?
I got a few classes that need got get info from MySQL to fill a ArrayList for example. I need authentication agains the MySQL database for users. Regular things. I understand how this should be done but not how to go about implementing it. Where should the DB connection be done so I dont have to make a connect in every method I want DB access in. Please, anything would be helpful.
Thanx in advance ...
/Roger

Hi all ...
My first post here. Hope Im at the right place. Welcome. You've come to the right spot.
>
I've just started out with java, had gotten the
basics and started to develop a little. Now, I would
like to involve a MySQL database. I have made a few
small connection tests and selections/insertions and
all works fine. Excellent.
Now, I have been googleing the net a few times but I
cant seem to find any good source of information on
how you implement the DB layer in an application. How
is it usually done? I don't think there's one way that everyone would agree on. I'm sure your Google search has turned up a lot of stuff: object-relational mapping, JDO, entity EJBs, the new Java Persistence API, straight JDBC.
One pattern that's popular these days is the Data Access Object, or DAO. Google for that and see what you think.
The idea is to isolate the SQL stuff into a single package of classes.
I got a few classes that need got get info from MySQL
to fill a ArrayList for example. I need
authentication agains the MySQL database for users.
Regular things. I understand how this should be done
but not how to go about implementing it.
Where should
the DB connection be done so I dont have to make a
connect in every method I want DB access in. I'm not sure what you mean by this, but I would say that a fresh connection for each database unit of work is a good idea. The idea is to get a connection when you need it, use it, and close it so somebody else can use it. It scales better that way.
You'll want to read about connection pooling, too.
%

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