JDBC in artifact

Hello, 

I changed sqlite to mysql and since then,I can't solve this problem. Sqlite used to work perfectly.

In IDE is all right, in jar not.

I tried these before connection

Class.forName("com.mysql.cj.jdbc.Driver").newInstance();
Class.forName("com.mysql.cj.jdbc.Driver");
Class.forName("com.mysql.jdbc.Driver").newInstance();
Class.forName("com.mysql.jdbc.Driver");
and without (connector v. 8.0.16) - just

String url = "jdbc:mysql://localhost:3306/jawler";
conn = DriverManager.getConnection(url, "name", "pass");

What am I doing wrong?

Thanks, Filip