在标准Java之后启动Java EE项目

Question

My task is to make a small a project for start my ee studies. Till now, I learned standard java, but i don't get what ee means exactly, how my project would be an enterprise stuff. Has it a different syntax or different setup in IDE? I know it's not a clever question, but I really don't know where to start. Do you have any idea for start a project?

Answer 1

Java EE is no different language or has no different syntax than Java SE. It's built on top of Java SE and comprises a set of standardized APIs and libraries that are helpful for solving problems in an enterprise context.

To name a few:

• Web Applications (Servlets, JSPs, JSF, WAR-packaging)
• RESTful- and WebServices (Jax-RS, Jax-WS)
• Persistence (EJB, JPA)
• Context Dependency Injection (CDI)
• Security
• Batch
• Messaging
• ...

Further it defines a runtime environment - an Application Server - to run enterprise applications. Nevertheless, the classic application server model has become somewhat obsolet, nowadays you either run a single application in an application server or use only parts of the libraries and APIs and embedd those in your applications.

So basically, all you need is an IDE and the libraries. When you're using maven as build environment, all you need is the java-ee maven dependency, see Maven Central

Usually you don't need to know all the libraries and APIs of Java EE in detail, it's good to know what is available out-of-the-box (so you don't reinvent the wheel), but you hardly will need all of them in all of your projects. I personally avoid JSF, hardly have to deal with JPA, only occasionally do something with Batch or EJBs. More common are CDI, Restful or WebServices and WebApps, and usually a bit of Security.

And a good example for a Java EE Projects, a simple one with some typical use cases and very little code is Adam Bien's Guestbook2.0 , which only requires Docker to run.