DriverManager.getConnection Question.

[Siddharth Bhargava]

Hi Friends,

I have a very basic question in JDBC. I am trying to connect to the database using JDBC.

Query:

Connection con = DriverManager.getConnection("url", "username", "password");

As per the documentation -> If successful then it returns the connection. If not then it gives an SQLException.

Please do let me know how should i check whether I have successfully got the connection to the database or not in my Java program ?

Could I check like this

if(con != null)
out.println("Successfully received the connection ");
else
out.println("Could not get the connection ....");

Thanks and Regards,
Sid

[Gamini Sirisena]

If there is some problem in getting a connection getConnection is supposed to throw an SQLException

by catching this you can decide on a course of action.. in general terms if there is an opportunity to recover then take than action.. if not you bubble up the Exception.. probably wrapped in an application specific Exception

[Siddharth Bhargava]

Gamini Sirisena wrote:If there is some problem in getting a connection getConnection is supposed to throw an SQLException

by catching this you can decide on a course of action.. in general terms if there is an opportunity to recover then take than action.. if not you bubble up the Exception.. probably wrapped in an application specific Exception

but can't I check as per below:

if(con != null)
out.println("Successfully received the connection ");
else
out.println("Could not get the connection ...."); 

[joyd das]

Wrap your exception properly to understand why Connection Object is null.
You can always have a check before start using the Connection Object . Important point always close the connection on finally block

Siddharth Bhargava wrote:

Gamini Sirisena wrote:If there is some problem in getting a connection getConnection is supposed to throw an SQLException

by catching this you can decide on a course of action.. in general terms if there is an opportunity to recover then take than action.. if not you bubble up the Exception.. probably wrapped in an application specific Exception

but can't I check as per below:

if(con != null)
out.println("Successfully received the connection ");
else
out.println("Could not get the connection ...."); 

[Dave Tolls]

Siddharth Bhargava wrote:
but can't I check as per below:

if(con != null)
out.println("Successfully received the connection ");
else
out.println("Could not get the connection ...."); 

But why would you when you can simply handle the exception (which is what is telling you you have no connection)?

try (getConnection){
    do whatever with the connection
} catch (SQLException ex) {
    log and do whatever is needed for this failure
}