This plugin gives random effect everytime after executing /randomeffect, Helpful for streamers to use the plugin on their own server
PotionEffectType randomEffect = validEffects.get(random.nextInt(validEffects.size()));
int durationSeconds = 10 + random.nextInt(111);
int durationTicks = durationSeconds * 20;
int amplifier = 1;
player.addPotionEffect(new PotionEffect(randomEffect, durationTicks, amplifier));