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diff --git a/docs/tutorials/005/page04.html b/docs/tutorials/005/page04.html deleted file mode 100644 index 2b117894588..00000000000 --- a/docs/tutorials/005/page04.html +++ /dev/null @@ -1,145 +0,0 @@ -<HTML> -<HEAD> -<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> -<META NAME="GENERATOR" CONTENT="Mozilla/4.04 [en] (X11; I; Linux 2.0.32 i486) [Netscape]"> -<META NAME="Author" CONTENT="Billy Quinn"> -<META NAME="Description" CONTENT="A first step towards using ACE productively"> -<TITLE>ACE Tutorial 005</TITLE> -</HEAD> -<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F"> - -<CENTER><B><FONT SIZE=+2>ACE Tutorial 005</FONT></B></CENTER> - -<CENTER><B><FONT SIZE=+2>On the road to a multithreaded server</FONT></B></CENTER> - - -<P> -<HR WIDTH="100%"> - -<P>Ok, so we've got a main() loop that sets up the acceptor and we've seen -how easy it is to create the acceptor object. So far, we've hardly -written any code at all. Well, that's just about to change... - -<P>First, we look at <I><A HREF="client_handler.h">client_handler.h</A></I> -for the declaration of the Client_Handler object. Then we look at -the definition where all of the real work of the application takes place. - -<P> -<HR WIDTH="100%"> - -<pre><FONT FACE="Arial,Helvetica"> -#ifndef CLIENT_HANDLER_H -#define CLIENT_HANDLER_H - -/* - Our client handler must exist somewhere in the ACE_Event_Handler object - hierarchy. This is a requirement of the ACE_Reactor because it maintains - ACE_Event_Handler pointers for each registered event handler. You could - derive our Client_Handler directly from ACE_Event_Handler but you still have - to have an ACE_SOCK_Stream for the actually connection. With a direct - derivative of ACE_Event_Handler, you'll have to contain and maintain an - ACE_SOCK_Stream instance yourself. With ACE_Svc_Handler (which is a - derivative of ACE_Event_Handler) some of those details are handled for you. - - */ - -#include "ace/Svc_Handler.h" - -#if !defined (ACE_LACKS_PRAGMA_ONCE) -# pragma once -#endif /* ACE_LACKS_PRAGMA_ONCE */ - -#include "ace/SOCK_Stream.h" - -/* - Another feature of ACE_Svc_Handler is it's ability to present the ACE_Task<> - interface as well. That's what the ACE_NULL_SYNCH parameter below is all - about. That's beyond our scope here but we'll come back to it in the next - tutorial when we start looking at concurrency options. - */ -class Client_Handler : public ACE_Svc_Handler < ACE_SOCK_STREAM, ACE_NULL_SYNCH > -{ -public: - - // Constructor... - Client_Handler (void); - - /* - The destroy() method is our preferred method of destruction. We could - have overloaded the delete operator but that is neither easy nor - intuitive (at least to me). Instead, we provide a new method of - destruction and we make our destructor protected so that only ourselves, - our derivatives and our friends can delete us. It's a nice - compromise. - */ - void destroy (void); - - /* - Most ACE objects have an open() method. That's how you make them ready - to do work. ACE_Event_Handler has a virtual open() method which allows us - to create this overrride. ACE_Acceptor<> will invoke this method after - creating a new Client_Handler when a client connects. Notice that the - parameter to open() is a void*. It just so happens that the pointer - points to the acceptor which created us. You would like for the parameter - to be an ACE_Acceptor<>* but since ACE_Event_Handler is generic, that - would tie it too closely to the ACE_Acceptor<> set of objects. In our - definition of open() you'll see how we get around that. - */ - int open (void *_acceptor); - - /* - When there is activity on a registered handler, the handle_input() method - of the handler will be invoked. If that method returns an error code (eg - -- -1) then the reactor will invoke handle_close() to allow the object to - clean itself up. Since an event handler can be registered for more than - one type of callback, the callback mask is provided to inform - handle_close() exactly which method failed. That way, you don't have to - maintain state information between your handle_* method calls. The _handle - parameter is explained below... - As a side-effect, the reactor will also invoke remove_handler() - for the object on the mask that caused the -1 return. This means - that we don't have to do that ourselves! - */ - int handle_close (ACE_HANDLE _handle, ACE_Reactor_Mask _mask); - -protected: - - /* - When we register with the reactor, we're going to tell it that we want to - be notified of READ events. When the reactor sees that there is read - activity for us, our handle_input() will be invoked. The _handleg - provided is the handle (file descriptor in Unix) of the actual connection - causing the activity. Since we're derived from ACE_Svc_Handler<> and it - maintains it's own peer (ACE_SOCK_Stream) object, this is redundant for - us. However, if we had been derived directly from ACE_Event_Handler, we - may have chosen not to contain the peer. In that case, the _handleg - would be important to us for reading the client's data. - */ - int handle_input (ACE_HANDLE _handle); - - /* - This has nothing at all to do with ACE. I've added this here as a worker - function which I will call from handle_input(). That allows me to - introduce concurrencly in later tutorials with a no changes to the worker - function. You can think of process() as application-level code and - everything elase as application-framework code. - */ - int process (char *_rdbuf, int _rdbuf_len); - - /* - We don't really do anything in our destructor but we've declared it to be - protected to prevent casual deletion of this object. As I said above, I - really would prefer that everyone goes through the destroy() method to get - rid of us. - */ - ~Client_Handler (void); -}; - -#endif // CLIENT_HANDLER_H -</pre> -<HR WIDTH="100%"> -<CENTER>[<A HREF="..">Tutorial -Index</A>] [<A HREF="page05.html">Continue This Tutorial</A>]</CENTER> - -</BODY> -</HTML> |