Extending Postgres implementation of Connection, PreparedStatement, ResultSet

[Jim Atharris]

Hello,

I was wondering if it is possible that the DriverManager can instantiate my implementations of those three classes. Each of those classes would extend the Postgres implementation:

public class MyCoolConnection extends org.postgresql.jdbc4.Jdbc4Connection
{
}

public class MyCoolPreparedStatement extends org.postgresql.jdbc4.Jdbc4PreparedStatement
{
}

public class MyCoolResultSet extends org.postgresql.jdbc4.Jdbc4ResultSet
{
}

So any .getClass().getName() on instances of the above class would return MyCool* and not postgres' implementation Jdbo4*.


Any ideas would be great.

Thanks,Jim

[Lester Burnham]

You didn't say what it actually is that you wish to accomplish, but maybe AOP (using a library like AspectJ) may help?

[Jim Atharris]

Lester Burnham wrote:You didn't say what it actually is that you wish to accomplish, but maybe AOP (using a library like AspectJ) may help?

One *possible* example for MyCoolConnection would have data members that based on a value may let the close() method get called in the base class. The real reason for this question ot the forum is proprietary business related and I cannot get into detail of it.

I would like to avoid AspectJ as that is introducing a COTS to our code base.

Thanks,Jim

[Lester Burnham]

Well, AspectJ is open source, so the risk (and financial cost) is limited.

But then, the Postgres JDBC driver is open source, too, so you can study -and adapt- it to your heart's content.

[Jim Atharris]

Lester Burnham wrote:Well, AspectJ is open source, so the risk (and financial cost) is limited.

But then, the Postgres JDBC driver is open source, too, so you can study -and adapt- it to your heart's content.

Postgres is just an example. Would also like to do this w/ Oracle's JDBC.

But you're right w/ Postgres and it being opensource. I was just reading the DriverManager class registerDriver() and seeing if I can do the following

    
public class MyExtendedDriver extends org.postgresql.Driver
{

}

But then it comes to the method below and it does not get called. So I'm wondering the semantics of DriverManager.registerDriver()

    
public Connection connect(String url, Properties info)