You have to open and close a JDBC connection in server side code like a RemoteServiceServlet subclass. You can find an example in http://www.gwtorm.com/mail/Mail.html. Source code is also available in http://code.google.com/p/dreamsource-orm/downloads/list.
You can use Dreamsource ORM for your GWT application. Jim Xie http://www.gwtorm.com http://code.google.com/p/dreamsource-orm/downloads/list On Apr 26, 8:06 am, barclay allen <[email protected]> wrote: > I'm starting a high traffic web application. I just setup a MySQL > server for GWT app. > > 1. Is the practical way still opening and closing a connection like > below? What about database connectivity with RPC? Below, for every > RPC service method call, I open a database connection, make a query, > and close connection. Is there a good practice way a web app is doing > database connectivity? Should I leave the connection open in the RPC > service since there will be a lot of RPC calls and just change the > query string? > > public class DB_QueryTest { > public static String query() { > String Query = "SELECT * FROM `tester`;"; > String resultString = ""; > try { > Connection connection = DB_Conn.getConn(); > Statement select = connection.createStatement(); > ResultSet result = select.executeQuery(Query); > > while (result.next()) { > resultString += result.getString(1); > } > connection.close(); > > } catch(Exception e) { > e.printStackTrace(); > } > return resultString; > } > > } > > --------------------------------------------------------------------------- > -------------------------------------------------------- > > //GreetingServiceImpl.java from GWT 1.6 RPC example, called when Send > button is clicked > @SuppressWarnings("serial") > public class GreetingServiceImpl extends RemoteServiceServlet > implements > GreetingService { > public String greetServer(String input) { > String serverInfo = getServletContext().getServerInfo(); > String userAgent = > getThreadLocalRequest().getHeader("User-Agent"); > > count++; > return "Hello, " + input + "!<br><br>I am running " + > serverInfo > + ".<br><br>It looks like you are using:<br>" > + userAgent > + "<br><br>My Query: " + DB_QueryTest.query(); > } > > } --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Google Web Toolkit" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/Google-Web-Toolkit?hl=en -~----------~----~----~----~------~----~------~--~---
