Java Reference
In-Depth Information
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Note
I want to stress that you will not be building a production-quality application. Some features and
functionality will be missing. This is due mainly to the fact that this is a beginning-level book, and we want to
demonstrate just the basics and not overwhelm you with endless lines of rote code. Try not to focus too much
on the functional requirements.
Technical Specifications
One of the great things about Google App Engine is that it supports so many
languages, libraries, and frameworks, giving you a large number of tools with which
to build your application. To implement your functional requirements you are going
to use GWT and several services and technologies provided by Google and App
Engine.
Authentication
Since you are using Java, you can roll your own authentication framework using
the servlet session interface, App Engine's data store, and its caching service. An
easier way, and the one you'll implement, is to use Google Accounts service. This
service allows App Engine to authenticate your users with Google Accounts,
providing for a much cleaner experience. App Engine can determine whether your
application's user has logged in with their Google accounts, and can redirect them
to the standard Google Accounts login page or allow them to create a new
account. App Engine can also detect whether the current user is a Google
Accounts administrator, making it easy to present them with content or
functionality applicable to their access level. You'll use Google Accounts to set up
authentication for your application in Chapter 6.
Presentation
App Engines supports a number of frameworks that should be familiar to the average
Java developer. Other frameworks are either totally incompatible (for example,
RichFaces) or semicompatible (for example, JBoss Seam, Wicket). As you saw in
Chapter 4, the App Engine environment provides you with a Java 6 JVM, a Java
servlets interface, and support for standard interfaces. This makes writing MVC web
applications very straightforward if you are familiar with servlets and JavaServer
Pages (JSPs).). Servlets and JSPs have their pros and cons but most seasoned
developers can get an application up and running in no time.
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