import javax.servlet.*; import javax.servlet.http.*; import java.io.*; import java.util.*; import java.sql.*; // This servlet demonstrates how an entire form can be generated // from a database. It would typically be called directly from // another web page (possibly as a redirect). public class ACMEForm extends HttpServlet implements SingleThreadModel { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { Connection con; PrintWriter out = response.getWriter(); response.setContentType("text/html"); try { // Register the driver (or the bridge). Class.forName("sun.jdbc.odbc.JdbcOdbcDriver"); //Class.forName("com.mysql.jdbc.Driver"); // Make the connection. con = DriverManager.getConnection("jdbc:odbc:ACME"); // con = DriverManager.getConnection("jdbc:mysql://localhost/ACME"); } // If there is a problem connecting, return an error message. catch(Exception ex) { out.println("

Error -- Database unreachable!

"); return; } // Construct a query that gets all items and their prices // from the Stock database, in order to create the form. String queryString = "SELECT Stock.Item, Stock.Price " + "FROM Stock"; try { // Create a new statement object. Statement s = con.createStatement(); // Execute the query on it. ResultSet rs = s.executeQuery(queryString); // Create the header information and start the form out.println("

ACME On-line Purchases

"); out.println("
"); out.println("Customer name:

"); out.println(""); // Cycle through the result set until no more records, and // build a simple html table to display the data, as well as // form elements to get quantity ordered. while (rs.next()) { // Extract the named fields from the current record String item = rs.getString("Item"); double price = rs.getDouble("Price"); // Write as a new table row out.println(""); out.println(""); // Note that for convenience we give the input element the // same name as the item. out.println(""); } // Close table and form, adding submit button out.println("
ITEMPRICEQUANTTIY
" + item + "$" + price + "


"); out.println("
"); // Close everything rs.close(); s.close(); con.close(); } // If the SQL string is not in the correct form, this will result // (it must be handled). The user should never be able to cause this. catch(SQLException ex) { out.println("

Error handling request!

"); return; } } }