Java EE (Java Enterprise Edition) General Discussion

I'm working with struts and mssql and i'm trying to insert data into db. select is workin fine, but insert does not. strange things is that i get no error message. this is the code i use:

Connection conn = null;
Statement stmt = null;

try
{
DataSource dataSource = (DataSource)servlet.getServletContext().getAttribute("org.apache.struts.action.DATA_SOURCE");
conn = dataSource.getConnection();
stmt = conn.createStatement();

stmt.executeUpdate("insert into wfKorisnik values('40', 'add1','city1','state1','country1','555','666','777','888')");
stmt.close();
conn.close();
}

catch(Exception e){
e.printStackTrace();
}


code that work:

DataSource dataSource = (DataSource)servlet.getServletContext().getAttribute("org.apache.struts.action.DATA_SOURCE");
try {
conn = dataSource.getConnection();
stmt = conn.createStatement();
int id = 0;
rs = stmt.executeQuery("select * from wfKorisnik");
rs.close();
stmt.close();
conn.close();
}
catch(Exception e){
e.printStackTrace();
}