first step you should cetain that your sql  server driver  is ok on your machine
and then you should create odbc  with your sql server  driver and test to connect  it correctly and then you could implement your jdbc :

private static final String driver = "sun.jdbc.odbc.JdbcOdbcDriver";
private static final String dsn = "jdbc:odbc:yourODBCname";
private Connection conn;

public static void main(String[] args) {

try {
  Class.forName(driver);
  conn = DriverManager.getConnection(dsn, "username", "password");
} catch(Exception e) {
    e.printStackTrace();
}
}