Chapter 18: Components; Component Basics - MACROMEDIA DREAMWEAVER 8-EXTENDING DREAMWEAVER Manual

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CHAPTER 18
Components
Macromedia Dreamweaver supports the creation of many of the most popular types of
components. In addition, Dreamweaver lets you extend the types of components that appear
in the Components panel.

Component basics

Programmers use various strategies to encapsulate their work. You can think of encapsulation
as creating an entity that exists in a virtual black box. To use it, you don't need to know how it
works; you only need to know what information it needs to do its job and what information it
will output after its job is complete. For example, a programmer might create a program that
gets information from an employee database. Anyone, including other programs, can then use
that program to query that database. Thus, the program is reusable.
Experience shows that well-organized programs that use encapsulation are easier to maintain,
enhance, and reuse. Different technologies offer programmers different ways to accomplish
this encapsulation, and different names describe these strategies: functions, modules, and
others. Macromedia Dreamweaver 8 uses the term component to refer to some of the more
popular and modern encapsulation strategies, including web services, JavaBeans, and
ColdFusion components (CFCs). So, when users build web applications in Dreamweaver, the
Components panel assists them in using available web services, JavaBeans, and CFCs.
Components from recent technologies (such as web services, JavaBeans, or CFCs) can
describe themselves. Usually there is information about the component embedded in the files
that constitute the component. The ability of a component to publish or share this
information is called introspection. In other words, a program such as Dreamweaver can ask a
component for a list of the functions it exposes (that is, functions that can be invoked from
another program). Depending on the technology in use, a component can reveal other
information about itself. For example, a web service might describe new data types.
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