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    <p>If we assume a (basic) <code>DataSource</code> (that is: one that does not do connection pooling), then you obtain a physical connection that is the same as one obtained from <code>DriverManager</code> (some drivers even internally use DriverManager from the DataSource, or a DataSource from DriverManager). So those connections will behave identically.</p> <p>Now if we assume a <code>DataSource</code> that provides connection pooling, then the DataSource itself uses a <code>ConnectionPoolDataSource</code> (or a similar internal mechanism) to obtain a <code>PooledConnection</code>. This PooledConnection manages the actual physical connection to the database.</p> <p>When a user requests a connection from the DataSource, the DataSource will checkout a PooledConnection, and ask it for a <code>Connection</code>. The PooledConnection will then create a logical connection that uses or wraps the physical connection (eg using a Proxy). The DataSource will return that logical connection to the user.</p> <p>To the user the logical connection should behave identical to a physical connection in all aspects. So when a user closes the connection, that logical connection and all dependent JDBC objects will be closed and behave identical to a physical connection close.</p> <p>JDBC 4.1 section 11.1 says:</p> <blockquote> <p>Connection pooling is completely transparent to the client: A client obtains a pooled connection and uses it just the same way it obtains and uses a non pooled connection.</p> </blockquote> <p>And section 11.4:</p> <blockquote> <p>If the application attempts to reuse the logical handle, the Connection implementation throws an SQLException.</p> </blockquote> <p>and</p> <blockquote> <p>For a given PooledConnection object, only the most recently produced logical Connection object will be valid. Any previously existing Connection object is automatically closed when the associated PooledConnection.getConnection method is called.</p> </blockquote> <p>In the background however, when the logical connection is closed, the PooledConnection will signal the DataSource that it is available for reuse, and the DataSource will then return it to the connection pool, or close the PooledConnection (which closes the physical connection) if it no longer needs the connection.</p> <p>The DataSource can also forcefully revoke a connection from a user (eg when a connection is checked out too long, etc), by asking the PooledConnection to close the logical connection.</p>
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    1. USMark Rotteveel
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    1. COIn my application, i'm able to access my `ResultSet` object even after I close my `Connection` object. So as per you note, Websphere failed this implementation?
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    2. COThat depends on what you mean with access. The ResultSet object will still exist, but you should not be able to use the ResultSet as it should have been closed when the logical connection was closed.
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    3. COAnd if it is an incorrect implementation of WebSphere: that depends on what you use as the `ConnectionPoolDataSource` for the `DataSource` of websphere. The behaviour I described should be enforced by the `PooledConnection` implementation.
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