Database JDBC Find out open connections/sessions?

Question

Is there anyway we can find out the open connections at a time when doing JPA operations for example.

To be more clear, I am getting no buffer space available error. So I want to know if i can close down my connections in my code in order to avoid this error?

Or if i can monitor it using some monitor tool what is happening etc.

It is a help request, if you can help I will be thankful, if you can't help then why are you down voting? This discourages from asking for help.

Answer 1

In my opinion it depends on the driver that your are using, some of them could have some way to know about it. But it is posible it could be a dangerous practice, because you could close a connection that is currently used.

The best way is to use a connection pool manager that take care about all the conections for instance:

http://www.mchange.com/projects/c3p0/index.html

Or integrate your database conections into and ORM for example hibernate:

http://hibernate.org/