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diff --git a/docs/tutorials/007/page07.html b/docs/tutorials/007/page07.html deleted file mode 100644 index 4c6905ebf33..00000000000 --- a/docs/tutorials/007/page07.html +++ /dev/null @@ -1,197 +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>Two new files this time. The first is <A HREF="thread_pool.h">thread_pool.h</A> -where we declare our Thread_Pool object. This is responsible for -abstracting away the thread pool implementation details and allowing us -to make so few changes to the rest of the code. - -<P> -<HR WIDTH="100%"><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica">// $Id: thread_pool.h,v 1.1 1998/08/30 -16:04:12 jcej Exp $</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica">#ifndef THREAD_POOL_H</FONT> -<BR><FONT FACE="Arial,Helvetica">#define THREAD_POOL_H</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica">/*</FONT> -<BR><FONT FACE="Arial,Helvetica"> In order to implement a thread -pool, we have to have an object that can create</FONT> -<BR><FONT FACE="Arial,Helvetica"> a thread. The ACE_Task<> -is the basis for doing just such a thing.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT> -<BR><FONT FACE="Arial,Helvetica">#include "ace/Task.h"</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica">/*</FONT> -<BR><FONT FACE="Arial,Helvetica"> We need a forward reference -for ACE_Event_Handler so that our enqueue() method</FONT> -<BR><FONT FACE="Arial,Helvetica"> can accept a pointer to one.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT> -<BR><FONT FACE="Arial,Helvetica">class ACE_Event_Handler;</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica">/*</FONT> -<BR><FONT FACE="Arial,Helvetica"> Although we modified the -rest of our program to make use of the thread pool</FONT> -<BR><FONT FACE="Arial,Helvetica"> implementation, if you look -closely you'll see that the changes were rather</FONT> -<BR><FONT FACE="Arial,Helvetica"> minor. The "ACE way" -is generally to create a helper object that abstracts</FONT> -<BR><FONT FACE="Arial,Helvetica"> away the details not relevant -to your application. That's what I'm trying</FONT> -<BR><FONT FACE="Arial,Helvetica"> to do here by creating the -Thread_Pool object.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT> -<BR><FONT FACE="Arial,Helvetica">class Thread_Pool : public ACE_Task<ACE_MT_SYNCH></FONT> -<BR><FONT FACE="Arial,Helvetica">{</FONT> -<BR><FONT FACE="Arial,Helvetica">public:</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> -/*</FONT> -<BR><FONT FACE="Arial,Helvetica"> -Provide an enumeration for the default pool size. By doing this, -other objects</FONT> -<BR><FONT FACE="Arial,Helvetica"> -can use the value when they want a default.</FONT> -<BR><FONT FACE="Arial,Helvetica"> -*/</FONT> -<BR><FONT FACE="Arial,Helvetica"> -enum size_t</FONT> -<BR><FONT FACE="Arial,Helvetica"> -{</FONT> -<BR><FONT FACE="Arial,Helvetica"> -default_pool_size_ = 5</FONT> -<BR><FONT FACE="Arial,Helvetica"> -};</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> -// Basic constructor</FONT> -<BR><FONT FACE="Arial,Helvetica"> -Thread_Pool(void);</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> -/*</FONT> -<BR><FONT FACE="Arial,Helvetica"> -Opening the thread pool causes one or more threads to be activated. -When activated,</FONT> -<BR><FONT FACE="Arial,Helvetica"> -they all execute the svc() method declared below.</FONT> -<BR><FONT FACE="Arial,Helvetica"> -*/</FONT> -<BR><FONT FACE="Arial,Helvetica"> -int open( int _pool_size = default_pool_size_ );</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> -/*</FONT> -<BR><FONT FACE="Arial,Helvetica"> -When you're done wit the thread pool, you have to have some way to shut -it down.</FONT> -<BR><FONT FACE="Arial,Helvetica"> -This is what close() is for.</FONT> -<BR><FONT FACE="Arial,Helvetica"> -*/</FONT> -<BR><FONT FACE="Arial,Helvetica"> -int close(void);</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> -/*</FONT> -<BR><FONT FACE="Arial,Helvetica"> -To use the thread pool, you have to put some unit of work into it. -Since we're</FONT> -<BR><FONT FACE="Arial,Helvetica"> -dealing with event handlers (or at least their derivatives), I've chosen -to provide</FONT> -<BR><FONT FACE="Arial,Helvetica"> -an enqueue() method that takes a pointer to an ACE_Event_Handler. -The handler's</FONT> -<BR><FONT FACE="Arial,Helvetica"> -handle_input() method will be called, so your object has to know when it -is being</FONT> -<BR><FONT FACE="Arial,Helvetica"> -called by the thread pool.</FONT> -<BR><FONT FACE="Arial,Helvetica"> -*/</FONT> -<BR><FONT FACE="Arial,Helvetica"> -int enqueue( ACE_Event_Handler * _handler );</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica">protected:</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> -/*</FONT> -<BR><FONT FACE="Arial,Helvetica"> -Our svc() method will dequeue the enqueued event handler objects and invoke -the</FONT> -<BR><FONT FACE="Arial,Helvetica"> -handle_input() method on each. Since we're likely running in more -than one thread,</FONT> -<BR><FONT FACE="Arial,Helvetica"> -idle threads can take work from the queue while other threads are busy -executing</FONT> -<BR><FONT FACE="Arial,Helvetica"> -handle_input() on some object.</FONT> -<BR><FONT FACE="Arial,Helvetica"> -*/</FONT> -<BR><FONT FACE="Arial,Helvetica"> -int svc(void);</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> -/*</FONT> -<BR><FONT FACE="Arial,Helvetica"> -Another handy ACE template is ACE_Atomic_Op<>. When parameterized, -this allows</FONT> -<BR><FONT FACE="Arial,Helvetica"> -is to have a thread-safe counting object. The typical arithmetic -operators are</FONT> -<BR><FONT FACE="Arial,Helvetica"> -all internally thread-safe so that you can share it across threads without -worrying</FONT> -<BR><FONT FACE="Arial,Helvetica"> -about any contention issues.</FONT> -<BR><FONT FACE="Arial,Helvetica"> -*/</FONT> -<BR><FONT FACE="Arial,Helvetica"> -typedef ACE_Atomic_Op<ACE_Mutex,int> counter_t;</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> -/*</FONT> -<BR><FONT FACE="Arial,Helvetica"> -We use the atomic op to keep a count of the number of threads in which -our svc()</FONT> -<BR><FONT FACE="Arial,Helvetica"> -method is running. This is particularly important when we want to -close() it down!</FONT> -<BR><FONT FACE="Arial,Helvetica"> -*/</FONT> -<BR><FONT FACE="Arial,Helvetica"> -counter_t active_threads_;</FONT> -<BR><FONT FACE="Arial,Helvetica">};</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica">#endif // THREAD_POOL_H</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P> -<HR WIDTH="100%"> - -<P>Well, that doesn't look too complex. What about the implementation? - -<P> -<HR WIDTH="100%"> -<CENTER>[<A HREF="..">Tutorial Index</A>] [<A HREF="page08.html">Continue -This Tutorial</A>]</CENTER> - -</BODY> -</HTML> |