diff options
Diffstat (limited to 'docs/tutorials/014/page05.html')
| -rw-r--r-- | docs/tutorials/014/page05.html | 215 |
1 files changed, 0 insertions, 215 deletions
diff --git a/docs/tutorials/014/page05.html b/docs/tutorials/014/page05.html deleted file mode 100644 index c654dd69a83..00000000000 --- a/docs/tutorials/014/page05.html +++ /dev/null @@ -1,215 +0,0 @@ -<HTML> -<HEAD> - <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> - <META NAME="Author" CONTENT="Bob McWhirter"> - <TITLE>ACE Tutorial 014</TITLE> -</HEAD> -<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F"> - -<CENTER><B><FONT SIZE=+2>ACE Tutorial 014</FONT></B></CENTER> - -<CENTER><B><FONT SIZE=+2>ACE_Stream Tutorial, Of Sorts</FONT></B></CENTER> - -<P> -<HR WIDTH="100%"> -<P> -Now we come to main(). In the previous task-chain tutorial - every thread pool had to have the same number of threads. This - time around, we leverage the construction method of ACE_Stream - and ACE_Module to customize the thread-pool size in each - ACE_Task of the stream. -<P> -Remember EndTask from the previous page? We create one here and push - it into the stream to take care of cleaning up the messages. - Technically, we could have replaced the default Tail task - created by the ACE framework but it seems to make more sense to - just push our "tail" onto the stream like the other tasks. The - caveat to this method is that you must be sure you don't push() - any other Modules behind the EndTask! -<P> -Once the stream of modules containing tasks is all setup then we can - put() some data into the stream for processing. The clever use - of Task::close() makes shutting downt the stream easier than - ever. No messing with hangup messages at the application level, - just close() when you're done! What could be simpler? -<P> -<HR WIDTH="100%"> -<PRE> - -// $Id$ - -// stream.cxx -// -// Tutorial regarding a way to use ACE_Stream. -// -// written by bob mcwhirter (bob@netwrench.com) -// -// - -#include "Task.h" -#include "EndTask.h" -// This is our specialized ACE_Task. - -#include <ace/Module.h> -#include <ace/Stream.h> -// These are the neccessary ACE headers. - - -typedef ACE_Module<ACE_MT_SYNCH> Module; -typedef ACE_Stream<ACE_MT_SYNCH> Stream; -// Just to avoid a lot of typing, typedefs -// are generally a good idea. - -int main(int argc, char *argv[]) -{ - cerr << __LINE__ << endl; - - int numberOfMessages = argc > 1 ? ACE_OS::atoi(argv[1]) : 3; - // unless otherwise specified, just send three messages - // down the stream. - - Stream theStream; - // the ACE_Stream itself. - - cerr << __LINE__ << endl; - - // Now, we instantiate 4 different Tasks. These do not - // need to be all the same class, but they do need to - // all derrive from the same flavor of ACE_Task. - // - // Also, we instantiate a fifth end-cap Task to clean - // up Message_Blocks as they reach the end. - - Task *taskOne; - Task *taskTwo; - Task *taskThree; - Task *taskFour; - Task *taskEnd; - - // Out Task's take two arguments: a name, and the number - // of threads to dedicate to the task. - - taskOne = new Task("Task No. 1", 1); - taskTwo = new Task("Task No. 2", 3); - taskThree = new Task("Task No. 3", 7); - taskFour = new Task("Task No. 4", 1); - - // Our EndTask only takes 1 argument, as it actually - // doesn't spawn any threads for processing. - - taskEnd = new EndTask("End Task"); - - Module *moduleOne; - Module *moduleTwo; - Module *moduleThree; - Module *moduleFour; - Module *moduleEnd; - - // ACE_Stream accepts ACE_Modules, which are simply a pair of - // ACE_Tasks. One is dedicated for writing, while the other - // is dedicated to reading. Think of the writing side as - // downstream, and the reading side as upstream. - // - // We're only working with a unidirection Stream today, - // so we'll only actually install a Task into the write - // side of the module, effectively downstream. - - cerr << __LINE__ << endl; - moduleOne = new Module("Module No. 1", taskOne); - moduleTwo = new Module("Module No. 2", taskTwo); - moduleThree = new Module("Module No. 3", taskThree); - moduleFour = new Module("Module No. 4", taskFour); - moduleEnd = new Module("Module End", taskEnd); - - cerr << __LINE__ << endl; - // Now we push the Modules onto the Stream. - // Pushing adds the module to the head, or - // otherwise prepends it to whatever modules - // are already installed. - - // So, you need to push() the modules on -backwards- - // from our viewpoint. - - if (theStream.push(moduleEnd) == -1) { - ACE_ERROR_RETURN ((LM_ERROR, "%p\n", "push"), -1); - } - - cerr << __LINE__ << endl; - if (theStream.push(moduleFour) == -1) { - ACE_ERROR_RETURN ((LM_ERROR, "%p\n", "push"), -1); - } - - // As we push a Module onto the Stream, it gets opened. - // When a Module open()s, it opens the Tasks that it contains. - // - // Since we cannot provide an argument to this embedded - // call to open(), we supplied specified the number of - // threads in the constructor of our Tasks. - - if (theStream.push(moduleThree) == -1) { - ACE_ERROR_RETURN ((LM_ERROR, "%p\n", "push"), -1); - } - - if (theStream.push(moduleTwo) == -1) { - ACE_ERROR_RETURN ((LM_ERROR, "%p\n", "push"), -1); - } - - if (theStream.push(moduleOne) == -1) { - ACE_ERROR_RETURN ((LM_ERROR, "%p\n", "push"), -1); - } - - cerr << __LINE__ << endl; - // Now that the Modules are open, the Tasks threads should - // be launching and entering their svc() loop, so we send - // some messages down the Stream. - - int sent = 1; - - ACE_Message_Block *message; - - while (sent <= numberOfMessages) { - - // First, create ourselves a Message_Block. - // see Tutorials 10-13 for more information - // about Message_Blocks and Message_Queues. - - message = new ACE_Message_Block(128); - - // Now, we grab the write-pointer from the Block, - // and sprintf() our text into it. - - ACE_OS::sprintf(message->wr_ptr(), "Message No. %d", sent); - - // All we have to do now is drop the Message_Block - // into the Stream. - - // It is always a good idea to duplicate() a Message_Block - // when you put it into any Message_Queue, as then - // you can always be allowed to release() your copy - // without worry. - - if (theStream.put(message->duplicate(), 0) == -1) { - ACE_ERROR_RETURN ((LM_ERROR, "%p\n", "put"), -1); - } - - message->release(); - ++sent; - } - - // Now that we've sent our Message_Blocks, close down - // the Stream. - // - // The Stream will automagically delete the Modules and - // the contained Tasks. We don't have to do that. - // - // This call will block (due to the way we've written our - // Task class) until all Message_Blocks have cleared the - // entire Stream, and all associated threads have exited. - - theStream.close(); - - return 0; -} -</PRE> -<P><HR WIDTH="100%"> -<CENTER>[<A HREF="..">Tutorial Index</A>] [<A HREF="page06.html">Continue This Tutorial</A>]</CENTER> |