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diff --git a/docs/tutorials/017/page03.html b/docs/tutorials/017/page03.html deleted file mode 100644 index 4513ed2260c..00000000000 --- a/docs/tutorials/017/page03.html +++ /dev/null @@ -1,90 +0,0 @@ -<HTML> -<HEAD> - <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> - <META NAME="Author" CONTENT="James CE Johnson"> - <TITLE>ACE Tutorial 017</TITLE> -</HEAD> -<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F"> - -<CENTER><B><FONT SIZE=+2>ACE Tutorial 017</FONT></B></CENTER> - -<CENTER><B><FONT SIZE=+2>Using the ACE_Barrier synch object</FONT></B></CENTER> - -<P> -<HR WIDTH="100%"> -The Barrier class used by the test task is a simple wrapper around -ACE_Barrier. One of the things about ACE_Barrier is that you have to -tell it how many threads it will be managing. Since that number -usually isn't known when you create your Task derivative, you have to -dynamically allocate the ACE_Barrier. My Barrier wrapper takes care -of that for you and even provides for a clean way to delete the -ACE_Barrier instance if you want to save a few bytes. -<P> -An interesting extension of this Barrier class would be to wrap it up -in a smart pointer. You could then have the Barrier destructor invoke -wait() as a now-protected method. The result would allow you to treat -the Barrier object almost as a "synchronization guard". -<HR> -<PRE> - -<font color=red>// $Id$</font> - -<font color=blue>#ifndef</font> <font color=purple>BARRIER_H</font> -<font color=blue>#define</font> <font color=purple>BARRIER_H</font> - -<font color=blue>#include</font> "<font color=green>ace/Synch.h</font>" - -<font color=red>/* Barrier is a simple wrapper for the ACE_Barrier synchronization - class. The ACE_Barrier is already pretty easy to use but I thought - I'd wrap it up to create just a bit more abstraction at the - application level. - */</font> -class Barrier -{ -public: - <font color=red>// Basic constructor and destructor. If you only need to</font> - <font color=red>// synch the start of your threads, you can safely delete your </font> - <font color=red>// Barrier object after invoking done(). Of course, you</font> - <font color=red>// should be careful to only delete the object once!</font> - Barrier(void); - ~Barrier(void); - - <font color=red>// Set and get the number of threads that the barrier will</font> - <font color=red>// manage. If you add or remove threads to your application</font> - <font color=red>// at run-time you can use the mutator to reflect that</font> - <font color=red>// change. Note, however, that you can only do that from the</font> - <font color=red>// thread which first created the Barrier. (This is a</font> - <font color=red>// limitation of my Barrier object, not the ACE_Barrier.)</font> - <font color=red>// The optional _wait parameter will cause wait() to be</font> - <font color=red>// invoked if there is already a valid threads value.</font> - int threads( u_int _threads, int _wait = 0); - u_int threads(void); - - <font color=red>// Wait for all threads to reach the point where this is</font> - <font color=red>// invoked. Because of the snappy way in which ACE_Barrier is </font> - <font color=red>// implemented, you can invoke these back-to-back with no ill-effects.</font> - int wait(void); - - <font color=red>// done() will invoke wait(). Before returning though, it</font> - <font color=red>// will delete the barrier_ pointer below to reclaim some memory.</font> - int done(void); - -protected: - <font color=red>// The number of threads we're synching</font> - ACE_Atomic_Op<ACE_Mutex,u_int> threads_; - - <font color=red>// The ACE_Barrier that does all of the work</font> - ACE_Barrier * barrier_; - - <font color=red>// The thread which created the Barrier in the first place.</font> - <font color=red>// Only this thread can change the threads_ value.</font> - ACE_thread_t owner_; - - <font color=red>// An internal method that constructs the barrier_ as needed.</font> - int make_barrier( int _wait ); -}; - -<font color=blue>#endif</font> <font color=red>// BARRIER_H</font> -</PRE> -<P><HR WIDTH="100%"> -<CENTER>[<A HREF="..">Tutorial Index</A>] [<A HREF="page04.html">Continue This Tutorial</A>]</CENTER> |