DO NOT REPLY [Bug 22079] - [DBCP] if connection closed twice *closed* connection is returned from the pool

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http://nagoya.apache.org/bugzilla/show_bug.cgi?id=22079

[DBCP] if connection closed twice *closed* connection is returned from the pool





------- Additional Comments From dirk.verbeeck@pandora.be  2003-08-09 19:38 -------
Original mail from Daniel
--------------------------
If I accidentally close DBCP connections twice, it will eventually cause the
JNDI datasource to start returning connections that are already closed.

Essentially my problem is this:

while (true)
{
  DataSource ds = getDataSourceFromJNDI();
  Connection conn = ds.getConnection();
  PreparedStatement ps = conn.prepareStatement("SELECT * FROM ......");
  ResultSet rs = ps.executeQuery();

  rs.close();
  ps.close();
  conn.close();

  // make the mistake of closing it twice
  conn.close();
}

Eventually getDataSourceFromJNDI() returns me a connection that's already
closed. In fact both it, and it's delegate, have the same object reference
IDs as the connections returned by the previous call.

This only happens if I use the connection to do something, and not if I just
create it and then close it.

I can always just wrap the connection in a proxy and then just not forward
on the close call if it's already been closed, but I figure that someone out
there might want to fix this properly and I can't find where I'm supposed to
commit bugs.

This sort of problem is best described in code, so I'm attaching it below.
It's a simple enough servlet that exposes this problem.