开始使用Google App Engine Java - 从哪个框架开始？

Question

I am new to both JAVA and Google App Engine. My Interest in Java stems from its compiled nature, speed and widespread enterprise use, whereas my interest in app engine is mainly because of it's initial free nature along with scalalbility.

I have been through Google's Getting Started and FAQ , I have modified the guestbook app and generally played around with the datastore, creating a simple entry system for use at work, using database schemas similar to the guestbook app. I come from a hackish PHP background, and most of my app consists of JSP pages with HTML and scriptlets mixed, with classes for the datastore stuff.

I have read about JSP, JSTL & JSF(not much) and also the basics of appengine, it's limitations,strengths and quotas. I also understand that my current approach is flawed. I have searched for JAVA frameworks and found one too many. I have been through the Will it play in App Engine list , but I do no half of the stuff mentioned there. I understand that webapp(used in the overview) is a framework and so is GWT. I understand I have to learn core java first. What framework should I begin with which is easy to use and also robust/secure enough to handle a financial app? The framework should also have value, if I were to host it in a pure J2EE environment independent of App Engine. I would appreciate a word on study resources too. Currently I see this book on amazon as a resource but are there cheaper alternatives like a library with a monthly subscription from where I can peruse similar books.(and I know that Google is a real good resource.) Are there any developers here who have apps hosted on appengine java and would like to share their personal experience of appengine java with a beginner?

I use Eclipse with the Google App Engine plugin to develop and upload my apps.

Answer 1

Regardless of what you want to do in Java you absolutely need to learn your way around the core language and the basic part of the runtime library.

The Java Tutorial covers this and is pretty straightforward.

Then you need to learn the Servlet API which underlies almost all Java-based web solutions today. Sun puts this in the full Java EE tutorial (which is a bit heavy) so have a look at this quick overview .

When you have gotten so far, you have a much better idea of what your basic toolbox is, and can give information allowing to give better advice on what technologies you should choose.

Sorry for the steep learning curve, but the view on top is fantastic.

Answer 2

If you aren't doing Java development currently, and/or haven't done much web development. I definitely wouldn't complicate things with adding frameworks.

What are you trying to accomplish that you need a framework for outside of the Google App Engine stack?

I've been developing with Java for years and only started using Spring with my Google App Engine app because I need a good security and authentication option. I wish I didn't have to use it since it's a rather steep learning curve.

You should be able to do most everything you need to for a simple app with JSP. If done correctly you can even do it in MVC if you wish.

Answer 3

On top of everything else people have recommended, I suggest you take a look at Objectify , a much simpler datastore API than the JDO/JPA ones included in the App Engine SDK.

This is, of course, after you've gotten familiar with the core of Java first.