Macromedia dreamweaver 8-extending dreamweaver User 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: functionsmodules, 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.