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POTrying to use connection pooling outside servlet engine
 

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    <p>I have a series of methods running within a servlet engine (Tomcat in this case), using connection pooling to access the database written in this way:</p> <pre><code>// Gets an RSS_Feed. public static RSS_Feed get(int rssFeedNo) { ConnectionPool_DB pool = ConnectionPool_DB.getInstance(); Connection connection = pool.getConnection(); PreparedStatement ps = null; ResultSet rs = null; String query = ("SELECT * " + "FROM RSS_Feed " + "WHERE RSSFeedNo = ?;"); try { ps = connection.prepareStatement(query); ps.setInt(1, rssFeedNo); rs = ps.executeQuery(); if (rs.next()) { return mapRSSFeed(rs); } else { return null; } } catch(Exception ex) { logger.error("Error getting RSS_Feed " + rssFeedNo + "\n", ex); return null; } finally { Database_Utils.closeResultSet(rs); Database_Utils.closeStatement(ps); pool.freeConnection(connection); } } </code></pre> <p>Is it possible to call such a method outside of the servlet engine at all? I would like to do this in a batch process executed from the command line instead of within the servlet engine. I know I could simply rewrite the query without connection pooling but this is one of many queries involved in the process.</p> <p>The connection pooling is implemented via Apache Common DBCP. </p> <p><strong><code>ConnectionPool_DB.getInstance();</code> reads:</strong></p> <pre><code>private ConnectionPool_DB() { try { InitialContext ic = new InitialContext(); dataSource = (DataSource) ic.lookup(PropertiesFile.getProperty("myApp", "DATASOURCE")); // dataSource = (DataSource) ic.lookup("java:/comp/env/jdbc/myApp"); } catch(Exception ex) { logger.error("Error getting a connection pool's datasource\n", ex); } } </code></pre>
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