DB Connection prob 2007-03-20 - By Richard Yee
Back
Graeme,
Since you mention that you are using a deployment descriptor, I am
assuming this is for a web application. If this is so, your application
is not going to be thread-safe b/c the connection is static and can be
used by different threads. If this is for a web application, you should
use a connection pool and a datasource. In your current problem, your
variables should not be final.
-Richard
Graeme McLaren wrote:
> Hi all, I have a prob connecting to my Oracle DB. I have a class called
> "DBConnection" and have various setter methods which set values found
> in the
> deployment descriptor, for example:
>
> public static void setDriver (String val) {
> driver = val;
> System.out.println("driver 2= "+driver); // I get the value
> displayed here so all is good at this point
> }
>
> I then have a getConnection method within this class:
>
> public static Connection getConnection(){
> try{
> Class.forName( driver ); // load the JDBC "driver" class
> connection = DriverManager.getConnection( dbURL, username,
> password );
> // get connection
>
> /*
> more code here
> */
>
> } // end of getConnection
>
>
>
> When I try to call getConnection() I get a nullpointerexception at
> Class.forName( driver ); as "driver" is set to null, why is this when the
> setter method sets the value?
>
> All variables are declared set to null and are static so they should
> be able
> to be set by the setter method shouldn't they? Just thinking about it
> now
> I'm thinking that when the variables are initialised to "null" that is
> them
> set and cannot be changed because they are static (and final), would
> that be
> right?
>
> How should I fix this?
>
>
> Cheers
>
> Graeme :)
>
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