This is a simple servlet to test everything is working ok. If this fails you have configuration problems. Best to keep it simple here so its easier to debug any config problems.
1. Start kawa.
Create a new file (name it DBConnection.java) and copy the text below or download the files here.
import javax.servlet.*;
import
javax.servlet.http.*;
import java.io.*;
import java.sql.*;
public class DBConnection extends
HttpServlet
{
public void doGet(HttpServletRequest req,
HttpServletResponse
res)
throws ServletException,
IOException
{
res.setContentType("text/html");
PrintWriter out = new
PrintWriter(res.getOutputStream());
try
{
Class.forName("org.gjt.mm.mysql.Driver").newInstance();
}
catch (Exception E)
{
out.println("Unable to load
driver.");
E.printStackTrace();
}
try
{
Connection conn =
DriverManager.getConnection("jdbc:mysql://localhost/javatutes?user=username&password=passwd");
// Do
something with the
Connection
try
{
// Use some connection
we've already created
Statement stmt =
conn.createStatement();
ResultSet rs =
stmt.executeQuery("SELECT jtutes_users.user_name FROM
jtutes_users");
out.println("<html>");
out.println("<head>");
out.println("<title>search
engine</title>");
out.println("</head>");
out.println("<body>");
out.println("<br>test
database connection");
while (rs.next())
{
out.println("<br>debug
user_name" +
rs.getString("user_name"));
}
out.println("</body>");
out.println("</html>");
// Clean up after
ourselves
rs.close();
stmt.close();
conn.close();
}
catch (SQLException E)
{
out.println("SQLException: " +
E.getMessage());
out.println("SQLState: " +
E.getSQLState());
out.println("VendorError: " +
E.getErrorCode());
}
}
catch
(SQLException E)
{
out.println("SQLException: " +
E.getMessage());
out.println("SQLState:
" + E.getSQLState());
out.println("VendorError: " +
E.getErrorCode());
}
out.close();
}
public String
getServletInfo()
{
return "Database
connection servlet";
}
}
3. Upload the directories and add the web.xml config file.
\webapps\jtutes\WEB-INF\web.xml
\webapps\jtutes\WEB-INF\classes
\webapps\jtutes\jsp\
4. restart tomcat
5. update mod_jk.conf-auto if your using manual configuration (ie a copy of this file is imported into apache httpd.conf)
6. restart tomcat
7. add the class files to your new context.
8. test the changes, should work like this.
9. Add some data, lets create an access database on our local development machine and connect to the mysql database on the remote linux server (across the internet). Create an access linked table.
10. choose odbc connection.
11. choose machine data source.
12. Add all the tables and select save password.
13. Edit the mysql database and check the changes using the servlet above, too easy.
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