MySQL, JNDI refactoring

[Zein Nunna]

Hi guys,

I'm trying to engineer my web application.

Hence any repeating code I'm trying to filter out.

My database code I have filtered out to a different class, which can then be invoked as and when the application needs to connect the database.

  
Context ctx = new InitialContext();
if (ctx == null)
throw new Exception("Boom - No Context");
ds = (DataSource) ctx.lookup("java:comp/env/jdbc/DB");
if (ds != null) {
connection = (Connection) ds.getConnection();  
...............

This throws an exception (Nullpointer... at line - this also throws a class cast exception )

ds = (DataSource) ctx.lookup("java:comp/env/jdbc/DB");

Now I'm guessing this is because the class is being invoked by another class, and hence no context is passed? How do I get round this? Any ideas?

Should I use a different methodology of refactoring my code?

Regards
Zein

[Herman Schelti]

hi Zein,

your code looks fine to me.

But what do you mean by "This throws an exception (Nullpointer... at line - this also throws a class cast exception )" ???

You can not cause a NullPointerException and a ClassCastException in 1 line in 1 run. Show us somelines of the stacktrace of your exception.

Herman

[Zein Nunna]

Right guys igonore this problem.

Ive got to the bottom of it.

I divided the DB connection code soo the connection/lookup is done by one method, and the execute query is done another method.

The reasoning behind this was you have 2 methods executeUpdate, and executeQuery in java hence this part would have been handled by different methods. This approach didnt work.

I've now put in some extra if/else statments and I do the whole connection/lookup/ execution of query in one method. It works fine.

Thanks anyway for looking into it.
Regards
Zein

[ March 07, 2007: Message edited by: Zein Nunna ]
[ March 07, 2007: Message edited by: Zein Nunna ]

[Jeanne Boyarsky]

Thanks for posting the solution so that others who see this thread in the future can benefit.