error in netbeans IDE 7.0 ,can not nonnected to databse(sql server2005)

import java.sql.*;

public class JavaApplication4 {

    /**
     * @param args the command line arguments
     */
    private static Connection link;
    
    public static void main(String[] args) {
try 
            {
                Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
                link = DriverManager.getConnection("jdbc:odbc: asd ","","");
                
                System.out.println("Connected to database");
            }
                catch(ClassNotFoundException cnfEx) 
                {
                    System.out.println("* Unable to load driver! *");
                    System.exit(1);
                }
                catch(SQLException sqlEx) 
                {
                    System.out.println("* Cannot connect to database! *");
                   System.out.println(sqlEx.getMessage());
                    System.exit(1);
                }

            try 
            {
                link.close();
                System.out.println("Disconnected to database");
            }
                catch(SQLException sqlEx) 
                {
                    System.out.println("* Unable to disconnect! *");
                    System.exit(1);
                }
         }
   }

* Cannot connect to database! *
[Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified