Apple WebObjects 5 - Manual (Page 37)

A Programmer’s View of WebObjects 37
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Apple Computer, Inc. January 2002
C H A P T E R 4
4 HTML-Based Applications
The HTML-based application approach allows you to create applications that
dynamically generate HTML pages. WebObjects provides graphical tools and a set
of flexible frameworks with which you can develop elaborate applications. This
chapter describes how a WebObjects HTML application works, the parts of a
WebObjects application the programmer sees, the advantages of using this
approach, and what the development process is like.
A Programmer’s View of WebObjects
The following features of WebObjects ease the development of HTML-based Web
applications:
■ The HTML and code reside in separate files. An object called a component
represents a Web page and consists of separate files for HTML and Java code.
■ WebObjects provides dynamic versions of static HTML elements. These are
called dynamic elements.
■ You can reuse HTML and Java code. Components can be embedded within
other components as if they were dynamic elements.
■ WebObjects automatically maintains state information. WebObjects
overcomes the inherent statelessness of HTTP and maintains session state (like
a shopping cart) and application state (like application statistics).
■ Your presentation code remains separate from your business logic. Enterprise
objects, discussed in “Enterprise Objects” (page 25), contain all of your business
logic. This allows you to reuse your business logic in multiple Web pages and
even multiple applications.