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diff --git a/docs/tutorials/013/page05.html b/docs/tutorials/013/page05.html deleted file mode 100644 index c258bfcd56a..00000000000 --- a/docs/tutorials/013/page05.html +++ /dev/null @@ -1,149 +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 013</TITLE> -</HEAD> -<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F"> - -<CENTER><B><FONT SIZE=+2>ACE Tutorial 013</FONT></B></CENTER> - -<CENTER><B><FONT SIZE=+2>Multiple thread pools</FONT></B></CENTER> - - -<P> -<HR WIDTH="100%"> -<P> -On this page we have the code for the Data_Block and Message_Block -objects. As you probably suspect from the header on the previous -page, the complicated part is in the construction and destruction of -the Data_Block. -<P> -<HR WIDTH="100%"> -<PRE> -#include "block.h" - -/* - Construct a Dat_Block to contain a unit of work. Note the careful - construction of the baseclass to set the block type and the locking - strategy. - <i>Also notice that we don't use the data area of the baseclass at - all. If we wanted to, we could have taken a second ctor parameter to - allow us the use of that space.</i> - */ -Data_Block::Data_Block( Unit_Of_Work * _data ) - : inherited(0,ACE_Message_Block::MB_DATA,0,0,new Lock(),0,0) - ,data_(_data) -{ - ACE_DEBUG ((LM_DEBUG, "(%P|%t) 0x%x Data_Block ctor for 0x%x\n", (void *) this, (void*)data_)); -} - -/* - The Lock object created in the constructor is stored in the - baseclass and available through the locking_strategy() method. We - can cast it's value to our Lock object and invoke the destroy() to - indicate that we want it to go away when the lock is released. - <i>In other tutorials I've gone to quite a bit of trouble to avoid - the kind of cast you see here. If I had stuck to that form it might - look something like this: - ACE_Lock * ls = this->locking_stragety(); - Lock * my_lock = (Lock*)ls; - my_lock->destroy();</i> - */ -Data_Block::~Data_Block(void) -{ - ACE_DEBUG ((LM_DEBUG, "(%P|%t) 0x%x Data_Block dtor for 0x%x\n", (void *) this, (void*)data_)); - ((Lock*)locking_strategy())->destroy(); - delete data_; -} - -/* - Return the data -*/ -Unit_Of_Work * Data_Block::data(void) -{ - return this->data_; -} - -Data_Block::Lock::Lock(void) - : destroy_(0) -{ - ACE_DEBUG ((LM_DEBUG, "(%P|%t) 0x%x Lock ctor\n", (void *) this )); -} - -Data_Block::Lock::~Lock(void) -{ - ACE_DEBUG ((LM_DEBUG, "(%P|%t) 0x%x Lock dtor\n", (void *) this )); -} - -/* - Set our destroy_ flag so that the next lock release will cause us to - be deleted. -*/ -int Data_Block::Lock::destroy(void) -{ - ++destroy_; - return(0); -} - -/* - Mutexes have acquire() and release() methods. We've overridden the - latter so that when the object we're protecting goes away, we can - make ourselves go away after the lock is released. -*/ -int Data_Block::Lock::release(void) -{ - int rval = inherited::release(); - if( destroy_ ) - { - delete this; - } - return rval; -} - -/* - Create an baseclass unit of work when we instantiate a hangup message. -*/ -Message_Block::Message_Block( void ) - : inherited( new Data_Block( new Unit_Of_Work() ) ) -{ - ACE_DEBUG ((LM_DEBUG, "(%P|%t) 0x%x Message_Block ctor for shutdown\n", (void *) this )); - this->msg_type( MB_HANGUP ); -} - -/* - Store the unit of work in a Data_Block and initialize the baseclass - with that data. -*/ -Message_Block::Message_Block( Unit_Of_Work * _data ) - : inherited( new Data_Block(_data) ) -{ - ACE_DEBUG ((LM_DEBUG, "(%P|%t) 0x%x Message_Block ctor for 0x%x\n", (void *) this, (void*)_data)); -} - -Message_Block::~Message_Block( void ) -{ - ACE_DEBUG ((LM_DEBUG, "(%P|%t) 0x%x Message_Block dtor\n", (void *) this )); -} -</PRE> -<HR WIDTH="100%"> -<P> -I hope that wasn't too confusing. The locking strategy can be a bit -daunting at times. The worst problem is dealing with the fact -that the lock is held while the object being guarded by the lock is -being destroyed. But the only object that has a reference to the -(dynamically created) lock object is the very thing being deleted. We -would be in a world of hurt if the lock's release() method had not -been created virtual! By simply overridding that method we can get -ourselves out of a nasty situation. -<P> -The rest of the code is pretty cut and dried. We could have had the -hangup indicator create a data block with a null unit of work but it's -more orthgonal for the thread pool if we always have a valid pointer. -<P> -<HR WIDTH="100%"> -<CENTER>[<A HREF="..">Tutorial Index</A>] [<A HREF="page06.html">Continue -This Tutorial</A>]</CENTER> - -</BODY> -</HTML> |