I have been searching for a good Java IRC client for a while and I finally found one. It’s called jIRCii. Being a Java application, no installation is needed. You only need to have Java runtime installed. DCC file transfer and CTCP are supported. The program also includes 70 built-in server aliases. I was able to logon to my favorite server and start using it right away. I am very impressed.
You can download it here.