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POHow do I call the Config.java in my servlet?
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  1. POHow do I call the Config.java in my servlet?
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    copied!<p>I've been trying really hard to figure out how to bring in this database connection into my servlet, but failed, and hence this posting here.</p> <p>Basically, I am using this code which I found my this site - one that is taught by BalusC.</p> <pre><code>public class Config implements ServletContextListener { private static final String ATTRIBUTE_NAME = "config"; private DataSource dataSource; @Override public void contextInitialized(ServletContextEvent event) { ServletContext servletContext = event.getServletContext(); String databaseName = servletContext.getInitParameter("pract1"); try { dataSource = (DataSource) new InitialContext().lookup("java:/comp/env/jdbc/TestDB"); } catch (NamingException e) { throw new RuntimeException("Config failed: datasource not found", e); } } @Override public void contextDestroyed(ServletContextEvent event) { System.out.println("contextDestroyed...."); } public DataSource getDataSource() { return dataSource; } public static Config getInstance(ServletContext servletContext) { return (Config) servletContext.getAttribute(ATTRIBUTE_NAME); } } </code></pre> <p>He explained that you have this class and the connection will start once for all the servlets, so I thought it's a good practice to do it.</p> <p>Now, my problem is that I do not know how to bring the database connection which is set up in the Config, the context.xml file, etc. to work in the servlet.</p> <p>Here's what I have attempted but it is not working out:</p> <pre><code>Connection con = null; Config a = new Config(); con = (Connection) a.getDataSource(); DBConnect dbConnect = new DBConnect(); con = dbConnect.getConnection(); stmt = con.createStatement(); rs = stmt.executeQuery("SELECT * FROM members"); </code></pre> <p>I hope someone can tell me how to bring the connection into my doPost Servlet.</p>
 

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