NullPointerException when executeBatch is called, and batch list is empty

try {

Class.forName("org.mariadb.jdbc.Driver");

String dbUrl = "jdbc:mysql://host:3306/db";

Connection con = DriverManager.getConnection(dbUrl, "user", "pwd");

Statement stmt = con.createStatement();

// do not add any batch entries!

stmt.executeBatch(); // -> NullPointerException

con.close();

}

catch(Exception ex) {

ex.printStackTrace();

}