Stephan, You need to make a request to the server for the data. The server can connect to the database and return the results to the browser. If your server is running Java, then GWT RPC is a good method. For non-Java servers, JSON could work for you.
See: http://code.google.com/webtoolkit/doc/1.6/DevGuideServerCommunication.html Hope that helps. - Isaac On Wed, Sep 2, 2009 at 10:24 PM, GumbyGWTBeginner<[email protected]> wrote: > > Can you guys point in the direction of either a concept on how I would > do this or a sample project for Ecllipse / GWT that I can go thru. > > Keeping in mind I am new at this too. > > I can figure most things out with sample code. > > My Secario: > I have installed MySQL Database on my PC > Trying to make a GWT application to interact with this Database > > In the hope to Base this on the same senario but on a web based > system. i.e. MySQL on a website and the GWT app interacting with this. > > Any help would greatly appricated. > > Thanks for the help thus far. > > Stephan > > > On Sep 3, 9:44 am, Isaac Truett <[email protected]> wrote: >> Hi, >> >> The problem is that you're trying to mix GWT and java.sql. That's not >> going to work. JS in the browser can't connect to your database. >> >> The cause of your specific error is that Class.forName() is not a part >> of the JRE that GWT emulates. >> >> See also:http://code.google.com/webtoolkit/doc/1.6/RefJreEmulation.html >> >> - Isaac >> >> On Wed, Sep 2, 2009 at 7:21 PM, >> >> >> >> GumbyGWTBeginner<[email protected]> wrote: >> >> > Hi Guys, >> >> > Was wondering if anyone could answer a small question? >> >> > I have created a class called DBFlow (Code below) which connects to >> > a MySQL DB and retrieve the number of rows in a DB. >> >> > I am new at this could anyone throw some light on the subject. >> >> > ****************Error Message**************** >> >> > [ERROR] Line 51: The method forName(String) is undefined for the type >> > Class >> >> > ****************Code to Call Class**************** >> >> > DBFlow TestTheDB = new DBFlow(); >> > TestTheDB.main(); >> >> > ****************Class Code**************** >> >> > import java.sql.Connection; >> > import java.sql.DriverManager; >> > import java.sql.ResultSet; >> > import java.sql.SQLException; >> > import java.sql.Statement; >> > import java.lang.Class; >> > import com.google.gwt.user.client.Window; >> >> > public class DBFlow { >> >> > public void onModuleLoad() { >> > //sdsd >> >> > } >> >> > public DBFlow() { >> > //sdsd >> >> > } >> >> > public void main() { >> > Connection conn = null; >> > try { >> > conn = getConnection(); >> > String tableName = "family"; >> > Window.alert("tableName=" + tableName); >> > Window.alert("conn=" + conn); >> > Window.alert("rowCount=" + countRows(conn, >> > tableName)); >> > } catch (Exception e) { >> > Window.alert("No Connect"); >> > e.printStackTrace(); >> > //System.exit(1); // Edit out as it is an erro >> > } finally { >> > // release database resources >> > try { >> > conn.close(); >> > } catch (SQLException e) { >> > e.printStackTrace(); >> > } >> > } >> > } >> >> > public Connection getConnection() throws Exception { >> > String driver = "com.mysql.jdbc.Driver"; >> > String url = "jdbc:mysql://localhost:3306/dogs"; >> > String username = "root"; >> > String password = "mypass"; >> >> > Class.forName(driver); // load MySQL driver >> > ***************************************Error here apprantly >> > Connection conn = DriverManager.getConnection(url, username, >> > password); >> > return conn; >> > } >> >> > public int countRows(Connection conn, String tableName) throws >> > SQLException { >> > // select the number of rows in the table >> > Statement stmt = null; >> > ResultSet rs = null; >> > int rowCount = -1; >> > try { >> > stmt = conn.createStatement(); >> > rs = stmt.executeQuery("SELECT COUNT(*) FROM " + >> > tableName); >> > // get the number of rows from the result set >> > rs.next(); >> > rowCount = rs.getInt(1); >> > } finally { >> > rs.close(); >> > stmt.close(); >> > } >> > return rowCount; >> > } >> >> > }- Hide quoted text - >> >> - Show quoted text - > > > --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
