
If you type 'javac' (which means java compiler) at terminal, you can see the following message:
jaeheon@ubuntu:~$ javac
'javac' 프로그램은 다음 꾸러미들에서 찾을 수 있습니다:
* openjdk-6-jdk
* ecj
* gcj-4.3
* java-gcj-compat-dev
* gcj-4.2
* jikes-classpath
* jikes-kaffe
* kaffe
* sun-java5-jdk
* sun-java6-jdk
I recommend the Java Development Kit supported by Sun Microsystems. The latest version is 6. So we can install it with,
jaeheon@ubuntu:~$ sudo apt-get install sun-java6-jdk