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diff --git a/docs/tutorials/007/page07.html b/docs/tutorials/007/page07.html deleted file mode 100644 index d200d598791..00000000000 --- a/docs/tutorials/007/page07.html +++ /dev/null @@ -1,132 +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> -<HR> -<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> - -<PRE> - -<font color=red>// $Id$</font> - -<font color=blue>#ifndef</font> <font color=purple>THREAD_POOL_H</font> -<font color=blue>#define</font> <font color=purple>THREAD_POOL_H</font> - -<font color=red>/* - In order to implement a thread pool, we have to have an object that can create - a thread. The ACE_Task<> is the basis for doing just such a thing. - */</font> -<font color=blue>#include</font> "<font color=green>ace/Task.h</font>" - -<font color=blue>#if !defined</font> (<font color=purple>ACE_LACKS_PRAGMA_ONCE</font>) -# pragma once -<font color=blue>#endif</font> <font color=red>/* ACE_LACKS_PRAGMA_ONCE */</font> - -<font color=red>/* - We need a forward reference for ACE_Event_Handler so that our enqueue() method - can accept a pointer to one. - */</font> -class ACE_Event_Handler; - -<font color=red>/* - Although we modified the rest of our program to make use of the thread pool - implementation, if you look closely you'll see that the changes were rather - minor. The "<font color=green>ACE way</font>" is generally to create a helper object that abstracts - away the details not relevant to your application. That's what I'm trying - to do here by creating the Thread_Pool object. - */</font> -class Thread_Pool : public ACE_Task<ACE_MT_SYNCH> -{ -public: - - typedef ACE_Task<ACE_MT_SYNCH> inherited; - - <font color=red>/* - Provide an enumeration for the default pool size. By doing this, other objects - can use the value when they want a default. - */</font> - enum size_t - { - default_pool_size_ = 5 - }; - - <font color=red>// Basic constructor</font> - Thread_Pool(void); - - <font color=red>/* - Opening the thread pool causes one or more threads to be activated. When activated, - they all execute the svc() method declared below. - */</font> - int open( int _pool_size = default_pool_size_ ); - - <font color=red>/* - Some compilers will complain that our open() above attempts to - override a virtual function in the baseclass. We have no - intention of overriding that method but in order to keep the - compiler quiet we have to add this method as a pass-thru to the - baseclass method. - */</font> - virtual int open(void * _void_data) - { return <font color=#008888>inherited::open</font>(_void_data); } - - <font color=red>/* - */</font> - int close( u_long flags = 0 ); - - <font color=red>/* - To use the thread pool, you have to put some unit of work into it. Since we're - dealing with event handlers (or at least their derivatives), I've chosen to provide - an enqueue() method that takes a pointer to an ACE_Event_Handler. The handler's - handle_input() method will be called, so your object has to know when it is being - called by the thread pool. - */</font> - int enqueue( ACE_Event_Handler * _handler ); - - <font color=red>/* - Another handy ACE template is ACE_Atomic_Op<>. When parameterized, this allows - is to have a thread-safe counting object. The typical arithmetic operators are - all internally thread-safe so that you can share it across threads without worrying - about any contention issues. - */</font> - typedef ACE_Atomic_Op<ACE_Mutex,int> counter_t; - -protected: - - <font color=red>/* - Our svc() method will dequeue the enqueued event handler objects and invoke the - handle_input() method on each. Since we're likely running in more than one thread, - idle threads can take work from the queue while other threads are busy executing - handle_input() on some object. - */</font> - int svc(void); - - <font color=red>/* - We use the atomic op to keep a count of the number of threads in which our svc() - method is running. This is particularly important when we want to close() it down! - */</font> - counter_t active_threads_; -}; - -<font color=blue>#endif</font> <font color=red>// THREAD_POOL_H</font> -</PRE> -<HR WIDTH="100%"> - -<P>Well, that doesn't look too complex. What about the implementation? - -<P><HR WIDTH="100%"> -<CENTER>[<A HREF="../online-tutorials.html">Tutorial Index</A>] [<A HREF="page08.html">Continue This Tutorial</A>]</CENTER> |