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diff --git a/docs/tutorials/006/page04.html b/docs/tutorials/006/page04.html deleted file mode 100644 index a43304af2e4..00000000000 --- a/docs/tutorials/006/page04.html +++ /dev/null @@ -1,153 +0,0 @@ -<!-- $Id$ --> -<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 006</TITLE> -</HEAD> -<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F"> - -<CENTER><B><FONT SIZE=+2>ACE Tutorial 006</FONT></B></CENTER> - -<CENTER><B><FONT SIZE=+2>Creating a thread-per-connection server</FONT></B></CENTER> - - -<P> -<HR WIDTH="100%"> -<P><A HREF="client_handler.h">client_handler.h</A> -shows a few more changes than the previous sources. The important -change is the addition of a svc() method where our connection thread will -exist. - -<P> -<HR WIDTH="100%"> -<PRE> -<font color=red>// $Id$</font> - -<font color=blue>#ifndef</font> <font color=purple>CLIENT_HANDLER_H</font> -<font color=blue>#define</font> <font color=purple>CLIENT_HANDLER_H</font> - -<font color=red>/* 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. - - */</font> - -<font color=blue>#include</font> "<A HREF="../../../ace/Svc_Handler.h">ace/Svc_Handler.h</A>" - -<font color=blue>#if !defined</font> (<font color=purple>ACE_LACKS_PRAGMA_ONCE</font>) -<font color=blue># pragma</font> <font color=purple>once</font> -<font color=blue>#endif</font> <font color=red>/* ACE_LACKS_PRAGMA_ONCE */</font> - -<font color=blue>#include</font> "<A HREF="../../../ace/SOCK_Stream.h">ace/SOCK_Stream.h</A>" - -<font color=red>/* 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. If our Client_Acceptor has chosen - thread-per-connection then our open() method will activate us into - a thread. At that point, our svc() method will execute. We still - don't take advantage of the things ACE_NULL_SYNCH exists for but - stick around for Tutorial 7 and pay special attention to the - Thread_Pool object there for an explanation. */</font> -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; - - <font color=red>// Constructor...</font> - Client_Handler (void); - - <font color=red>/* 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. */</font> - void destroy (void); - - <font color=red>/* 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. */</font> - int open (void *acceptor); - - <font color=red>/* 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. */</font> - int close (u_long flags = 0); - - <font color=red>/* 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! */</font> - virtual int handle_close (ACE_HANDLE handle = ACE_INVALID_HANDLE, - ACE_Reactor_Mask mask = <font color=#008888>ACE_Event_Handler::ALL_EVENTS_MASK</font>); - -protected: - - <font color=red>/* 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. */</font> - int svc (void); - - <font color=red>/* 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 <handle> would - be important to us for reading the client's data. */</font> - int handle_input (ACE_HANDLE handle); - - <font color=red>/* 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(). As - promised in Tutorial 5 I will use this now to make it easier to - switch between our two possible concurrency strategies. */</font> - int process (char *rdbuf, int rdbuf_len); - - <font color=red>/* 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. */</font> - ~Client_Handler (void); -}; - -<font color=blue>#endif</font> <font color=red>/* CLIENT_HANDLER_H */</font> -</PRE> -<HR WIDTH="100%"> - -<P>So... we've added a svc() method and alluded to changes in open(). -Let's move on to the object definition and see what all the fuss is about. - -<P> -<P><HR WIDTH="100%"> -<CENTER>[<A HREF="../online-tutorials.html">Tutorial Index</A>] [<A HREF="page05.html">Continue This Tutorial</A>]</CENTER> |