I know this is a little off topic, but what language is that? Looks like java, but I am not sure.
To help, it looks like everything is in order. PASS first with the included oauth:token and then the NICK username.
Can I ask how you are generating your token? Are you using the Twitch OAuth Token Generator for it? Maybe the token is invalid and you aren’t getting the errors. You should use the https://id.twitch.tv/oauth2/validate hook before logging into IRC anyways per the Twitch API TOS. If you can’t do that, then telnet into irc.twitch.tv and run through it manually to see what errors you get.