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The Phases of the Request-Response Loop

When the adaptor receives a request for a page from the HTTP server, it sends the message handleRequest: to the WebObjects application that "owns" the page. This message sets in motion a cycle of the request-response loop. This cycle consists of three phases:

Each phase is associated with a message originated by the application object. Each message passes from application to session, from session to component, and from component to (potentially) each HTML element the component contains.

A note on terminology: In WebObjects, a page in a browser is represented by a WOComponent object, or simply, a component. Conceptually, this relationship is so strong, that "page" and "component" are synonymous in many of the discussions that follow. In other words, "request page" usually refers to the same thing as "request component." However, components are not always identified with an entire page; you can have nested components, called subcomponents or reusable components, that occupy only a portion of a page. See "Subcomponents and Component References" for more on subcomponents.

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