I not only studied Java but also worked with it a good few times. In overall I like the system, my expertise is based upon the following:
- Persistence(JPA/Toplink) and JDBC
- JSP, JSF and Velocity templates
- Java Swing - though I haven't done that for a while...
- Tomcat configurations and management
- NetBeans and Eclipse use
- GIT Source control management
- ...again...pretty much anything