HTTP protocol execution framework. Apart from simply sending and receiving messages, there are a lot of things to consider when communicating with HTTP. Many details such as transport encodings or connection management are handled by setting up or interpreting {@link org.apache.http.Header headers} in the messages. In order to relieve applications from the responsibility of implementing these nitty-gritty details of the protocol, HTTP components provides an execution framework that sets up some of the headers before sending a message, and interprets headers when a message has been received.
An HTTP {@link org.apache.http.protocol.HttpProcessor processor} typically keeps lists of so-called interceptors that will be executed before a message is sent and after it has been received. An application should initialize a processor, set up the lists with the required and desired processors, and then communicate through that processor. There are four kinds of interceptors, depending on whether they act on {@link org.apache.http.HttpRequestInterceptor requests} or {@link org.apache.http.HttpResponseInterceptor responses}, on the client or server side:

	Client	Server
Request	prepares headers before a request is sent	interprets headers when a request is received
Response	interprets headers when a response is received	prepares headers before a response is sent

{@link org.apache.http.protocol.HttpRequestExecutor HttpRequestExecutor} is a processor for the client side, {@link org.apache.http.protocol.HttpService HttpService} for the server side. On the client side, a {@link org.apache.http.protocol.HttpContext context} is used to tie together a request, the response to it, and other data that might be associated with the request execution. It is passed to the request executor whenever needed.

Information about required and recommended interceptors for the client side will be provided elsewhere. For the time being, please refer to the comments in the example applications or ask on one of the mailing lists.

Note: If you want to develop a server-side application, we recommend that you implement your application as a servlet running in a servlet engine like Tomcat or full-blown JSEE container like Geronimo. If you prefer to implement a server-side application based on our {@link org.apache.http.protocol.HttpService HttpService}, we'll assume that you know what you're doing and that you don't need help in figuring out which interceptors need to be configured.