Re: connection pool

From:
Robert Klemme <shortcutter@googlemail.com>
Newsgroups:
comp.lang.java.programmer
Date:
Sat, 26 Jun 2010 21:45:39 +0200
Message-ID:
<88n3n4Fgc8U1@mid.individual.net>
On 06/26/2010 05:20 PM, Lew wrote:

gk wrote:

We write

Context ctx = new InitialContext()
javax.sql.DataSource ds = (DataSource)ctx.lookup("jdbc/oracleLink");
Connection con = ds.getConnection();

We get connection now. Is there any way to get minimum, current and
maximum number of connections in the pool at this part ?


I don't see a way using the java.* or javax.* SQL APIs. This part
would be the wrong place for that information anyway.

The whole point of connection pools is to provide the pooling facility
transparently, that is, in a way that looks to the application just
like a non-pooled connection. The segregation of pooling capability
from normal DataSource and Connection usage is deliberate.

There probably is a way using driver-specific calls. WebLogic has
management beans that can reveal this information:
<http://download.oracle.com/docs/cd/E14571_01/apirefs.1111/e13951/core/
index.html>
Click on "JDBCConnectionPoolParamsBean"

Meta-information about the connection should be logically separate
from actual use of the connection.


Similar in JBoss which exhibits an MBean providing information about a
pool's state.

Kind regards

    robert

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