You can’t possibly know all the Java technologies out there because no company will give you a chance to. One company will swear by the Spring framework while other companies like LinkedIn have moved on and are into the PlayFramework.
However, let me give you a list of 10 technologies that will always pitch you ahead of your competition regardless of the company.
10 Skills that will make you a great Java Developer:
- At least one MVC Framework like JSF, Playframework, Struts, or Spring MVC
- Hibernate or JPA for databases
- Dependency Injection (@Resource)
- SOAP based Web Services (JAX-WS)
- Some build tool (Ant, Maven, etc.)
- JUnit (or other Unit Testing framework)
- Version Control mostly Git
- JSTL
- Application server/container configuration management and application deployment (whether it is WebSphere, Tomcat, JBoss, etc. you need to know where your application runs and how to improve its execution)
- AJAX
Nonetheless being a smart Java developer takes more that just knowing your stuck.
Success!