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Servlet Update Database

import java.io.*; import java.sql.*; import javax.servlet.*; import javax.servlet.http.*; public class MyServlet extends HttpServlet {   public void doPost(HttpServletRequest req, HttpServletResponse res)                                 throws ServletException, IOException {     res.setContentType("text/plain");     PrintWriter out = res.getWriter();     Connection con = null;     try {       Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");       con = DriverManager.getConnection("jdbc:odbc:ordersdb", "user", "passwd");       // Turn on transactions       con.setAutoCommit(false);       Statement stmt = con.createStatement();       stmt.executeUpdate("UPDATE INVENTORY SET STOCK = (STOCK - 10) ");       stmt.executeUpdate("UPDATE SHIPPING SET SHIPPED = (SHIPPED + 10)");       con.commit();       out.println("Order successful!  Thanks for your business!");     }     catch (Exception e) {       // Any error is grounds for rollback       try {         con.rollback();       }       catch (SQLException ignored) { }       out.println("Order failed. Please contact technical support.");     }     finally {       // Clean up.       try {         if (con != null) con.close();       }       catch (SQLException ignored) { }     }   } } <?xml version="1.0" encoding="iso-8859-1"?> <!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN" "http://java.sun.com/dtd/web-app_2_3.dtd"> <web-app>     <servlet><servlet-name>MyServletName</servlet-name>              <servlet-class>MyServlet</servlet-class>     </servlet>          <servlet-mapping><servlet-name>MyServletName</servlet-name>         <url-pattern>*.htm</url-pattern>     </servlet-mapping>   <context-param>     <param-name>javax.servlet.jsp.jstl.fmt.timeZone</param-name>     <param-value>US/Central</param-value>   </context-param>   <context-param>     <param-name>database-driver</param-name>     <param-value>org.gjt.mm.mysql.Driver</param-value>   </context-param>   <context-param>     <param-name>database-url</param-name>     <param-value>     jdbc:mysql://localhost/forum?user=forumuser</param-value>   </context-param> </web-app>