Re: Exception in DriverManager.getConnection creates multiple connections in SYN_SEND state

Emanuel Freitas wrote:
> I'm running a server that receives approximately 300 requests per
> second. For each request I need to do some operations in a database. So,
> when I receive a request i [sic] check if there is any active connection to
> the database and if not i [sic] create one. The code for create the connection
> is something like this:
>
> private Connection initConn() {
>
> try {
> Class.forName("org.postgresql.Driver");

You only need to load the driver class once. Load it in a static initializer
block.

> } catch (ClassNotFoundException cnfe) {
> System.err.println("Error on Driver");

Consider using a logging framework like log4j or java.util.logging.

> return null;

Consider stopping the application for this particular exception.

> }
>
> try {
>
> Connection db =
> DriverManager.getConnection("jdbc:postgresql://192.168.1.2:5432/test?loginTimeout=3
> http://192.168.1.2:5432/test?loginTimeout=3", "test", "1234");

Consider externalizing the connection details. Try persistence.xml,
context.xml or an application server's setup script/screen to create a data
source.

> return db;
>
> } catch (SQLException sqle) {
> System.err.println("Error on Connection");
> return null;

You might want to log more details (again, using a logger) to troubleshoot
this scenario. One candidate detail is the SQLState.

> }
> }

--
Lew