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Using a connection class?

 
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I am creating a Java connection to a MySQL database and I have several different classes which will be utilizing that connection for various purposes. This will involve different MySQL user accounts where the user logs in to the database and performs the necessary actions.

So, I guess my question is:
Is there a way to create a Connection class for a persistent connection to the database, so long as a specified user is logged into the system, that can be reused in other classes for authentication? If so, how can I use

If I am trying to go about this all wrong then let me know that as well.

Any help would be very....Helpful!

Thanks,
Bryan
 
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A connection is tied to a user. While you can keep open a connection and pass it around to different classes, it will always be for that specific user. For a different user, you have to open a new connection.
 
Bryan Scarbrough
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Is there a way to place the following in its own class:



I am trying to prevent placing this into every file class that I am using for queries.

Thanks for your reply.
Hope this is a little more clear.
 
Ulf Dittmer
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You can make it a static method in some utility class. That way you can access it from everywhere. The Class.forName().getInstance() only needs to be done once - you don't need to repeat it for every connection.
 
Bryan Scarbrough
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Once I set it up as a method to a utility class, then how can I reuse that information? Is there a way I can return the result set and then utilize that for creating statements, etc? If so, how?

I have been working on this for a couple of days now and more hours than I care to admit and I am completely lost at this point!
 
Ulf Dittmer
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It would go something like this: In Helperclass.java you would have:

public static Connection getConnection (String url, String user, String password) {
try {
return DriverManager.getConnection( url, user, password );
} catch( Exception x ) {
System.err.println( x );
return null;
}

and then in your application:

static {
try {
Class.forName( driver ).newInstance("com.mysql.jdbc.Driver");
} catch (Exception ex) {
System.err.println(ex.getMessage());
}
}

and later on

Connection con = Helperclass.getConnection(url, user, password);
// do something with con; of course, it could be null!

If the URL is always the same (i.e., you're using the same DB all the time), you could have the helper class take care of that as well.
[ August 09, 2005: Message edited by: Ulf Dittmer ]
 
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