Testing a custom BCryptPasswordEncoder class

I have a class that looks like this

@Component
public class SecurityUtility {

    private final String SALT = "salt";

    @Bean
    public BCryptPasswordEncoder passwordEncoder() {
        return new BCryptPasswordEncoder(12, new SecureRandom(SALT.getBytes()));
    }

    @Bean
    public String randomPassword() {
        String SALTCHARS = "ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890";
        StringBuilder salt = new StringBuilder();
        Random rnd = new Random();

        while (salt.length() < 18) {
            int index = (int) (rnd.nextFloat() * SALTCHARS.length());
            salt.append(SALTCHARS.charAt(index));
        }
        String saltStr = salt.toString();
        return saltStr;
    }
}

What can I do to test such a class and how do I go about it , normally I have been doing unit tests but this class , don't know what type of test or how to go about it . Thank you in advance for any suggestion