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diff --git a/docs/tutorials/007/page05.html b/docs/tutorials/007/page05.html deleted file mode 100644 index c797b188cec..00000000000 --- a/docs/tutorials/007/page05.html +++ /dev/null @@ -1,208 +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="James CE Johnson"> - <META NAME="Description" CONTENT="A first step towards using ACE productively"> - <TITLE>ACE Tutorial 007</TITLE> -</HEAD> -<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F"> - -<CENTER><B><FONT SIZE=+2>ACE Tutorial 007</FONT></B></CENTER> - -<CENTER><B><FONT SIZE=+2>Creating a thread-pool server</FONT></B></CENTER> - - -<P> -<HR WIDTH="100%"> - -<P>As you might expect, <A HREF="client_handler.h">client_handler.h</A> -is next. - -<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" - -class Client_Acceptor; -class Thread_Pool; - -/* - 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: - typedef ACE_Svc_Handler < ACE_SOCK_STREAM, ACE_NULL_SYNCH > inherited; - - // 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 an ACE_Task<> object falls out of the svc() method, the framework - will call the close() method. That's where we want to cleanup ourselves - if we're running in either thread-per-connection or thread-pool mode. - */ - int close(u_long flags = 0); - - /* - 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); - - /* - 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); - -protected: - - /* - If the Client_Acceptor which created us has chosen a thread-per-connection - strategy then our open() method will activate us into a dedicate thread. - The svc() method will then execute in that thread performing some of the - functions we used to leave up to the reactor. - */ - int svc(void); - - /* - 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); - - /* - When we get to the definition of Client_Handler we'll see that there are - several places where we go back to the Client_Acceptor for information. - It is generally a good idea to do that through an accesor rather than - using the member variable directly. - */ - Client_Acceptor * client_acceptor( void ) - { return this->client_acceptor_; } - - /* - And since you shouldn't access a member variable directly, neither should you - set (mutate) it. Although it might seem silly to do it this way, you'll thank - yourself for it later. - */ - void client_acceptor( Client_Acceptor * _client_acceptor ) - { this->client_acceptor_ = _client_acceptor; } - - /* - The concurrency() accessor tells us the current concurrency strategy. It actually - queries the Client_Acceptor for it but by having the accessor in place, we could - change our implementation without affecting everything that needs to know. - */ - int concurrency(void); - - /* - Likewise for access to the Thread_Pool that we belong to. - */ - Thread_Pool * thread_pool(void); - - - Client_Acceptor * client_acceptor_; - - /* - For some reason I didn't create accessor/mutator methods for this. So much for - consistency.... - - This variable is used to remember the thread in which we were created: the "creator" - thread in other words. handle_input() needs to know if it is operating in the - main reactor thread (which is the one that created us) or if it is operating in - one of the thread pool threads. More on this when we get to handle_input(). - */ - ACE_thread_t creator_; -}; - -#endif // CLIENT_HANDLER_H -</pre> -<HR WIDTH="100%"> - -<P>Still, we're just not seeing a lot of changes due to intruduction of -the thread pool. That's a good thing! You don't want to go turning -your application upside down just because you changed thread models. - -<P> -<HR WIDTH="100%"> -<CENTER>[<A HREF="..">Tutorial -Index</A>] [<A HREF="page06.html">Continue -This Tutorial</A>]</CENTER> - -</BODY> -</HTML> |