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diff --git a/docs/tutorials/016/page04.html b/docs/tutorials/016/page04.html deleted file mode 100644 index 75c953961cc..00000000000 --- a/docs/tutorials/016/page04.html +++ /dev/null @@ -1,272 +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 016</TITLE> -</HEAD> -<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F"> - -<CENTER><B><FONT SIZE=+2>ACE Tutorial 016</FONT></B></CENTER> - -<CENTER><B><FONT SIZE=+2>Making ACE_Condition easier to use</FONT></B></CENTER> - -<P> -<HR WIDTH="100%"> -We finally get to the main() application. I create a simple Task -derivative that will serve as a baseclass for other objects that test -specific functions of the Condition class. Notice how easy it is to -integrate a Condition into the application without keeping track of -three related member variables. -<HR><PRE> - -<font color=red>// $Id$</font> - -<font color=blue>#include</font> "<font color=green>Condition_i.h</font>" -<font color=blue>#include</font> "<font color=green>ace/Task.h</font>" - -<font color=red>/* In order to test our Condition we'll derive from ACE_Task<> so that - we can have several threads accessing the condition variable - together. - */</font> -class Test : public ACE_Task<ACE_NULL_SYNCH> -{ -public: - <font color=red>// Construct the condition variable with an initial value.</font> - Test( <font color=#008888>Condition::value_t</font> _value ); - ~Test(void); - - <font color=red>// Open the Task with enough threads to make a useful test.</font> - int open(void); - -protected: - <font color=red>// Each thread will do work on the Condition.</font> - int svc(void); - - <font color=red>// Override this method to modify the Condition in some way.</font> - virtual void modify(void) = 0; - <font color=red>// Override this to test the Condition in some way.</font> - virtual void test(void) = 0; - - <font color=red>// How many threads to use in the test. This is also used in the</font> - <font color=red>// modify() and test() methods of the derivatives.</font> - static const int max_threads_; - - <font color=red>// We want to sleep for a random amount of time to simulate</font> - <font color=red>// work. The seed is necessary for proper random number generation.</font> - ACE_RANDR_TYPE seed_; - - <font color=red>// This is the actual condition variable set.</font> - Condition condition_; -}; - -<font color=red>// Set the number of threads.</font> -const int <font color=#008888>Test::max_threads_</font> = 5; - -<font color=red>// Initialize the condition variable.</font> -<font color=#008888>Test::Test</font>( Condition::value_t _value ) - : condition_(_value) -{ - ; -} - -<font color=#008888>Test::~Test</font>(void) -{ - ; -} - -<font color=red>// Seed the random number generator and start the threads.</font> -int <font color=#008888>Test::open</font>(void) -{ - seed_ = <font color=#008888>ACE_OS::gettimeofday</font>().usec(); - - <font color=#008888>ACE_OS::srand</font>( seed_ ); - - return this->activate(THR_NEW_LWP, max_threads_); -} - -<font color=red>/* Each thread will modify the condition variable in some way and then - wait for the condition to be satisfied. The derived classes - overload modify() and test() to implement a specific test of the - Condition class. - */</font> -int <font color=#008888>Test::svc</font>(void) -{ - <font color=red>// Take a moment before we modify the condition. This will</font> - <font color=red>// cause test() in other threads to delay a bit.</font> - int stime = <font color=#008888>ACE_OS::rand_r</font>( seed_ ) % 5; - <font color=#008888>ACE_OS::sleep</font>(abs(stime)+2); - - ACE_DEBUG ((LM_INFO, "<font color=green>(%P|%t|%T)\<font color=#008888>tTest::svc</font>() befor modify, condition_ is: %d\n</font>", (int)condition_ )); - - <font color=red>// Change the condition variable's value</font> - modify(); - - ACE_DEBUG ((LM_INFO, "<font color=green>(%P|%t|%T)\<font color=#008888>tTest::svc</font>() after modify, condition_ is: %d\n</font>", (int)condition_ )); - - <font color=red>// Test for the condition we want</font> - test(); - - ACE_DEBUG ((LM_INFO, "<font color=green>(%P|%t|%T)\<font color=#008888>tTest::svc</font>() leaving.\n</font>" )); - - return(0); -} - -<font color=red>/* Test <font color=#008888>Condition::operator</font>!=() - The task's svc() method will increment the condition variable and - then wait until the variable's value reaches max_threads_. - */</font> -class Test_ne : public Test -{ -public: - <font color=red>// Initialize the condition variable to zero since we're counting up.</font> - Test_ne(void) - : Test(0) - { - ACE_DEBUG ((LM_INFO, "<font color=green>\n(%P|%t|%T)\tTesting condition_ != %d\n</font>", max_threads_)); - } - - <font color=red>// Increment the variable</font> - void modify(void) - { - ++condition_; - } - - <font color=red>// Wait until it equals max_threads_</font> - void test(void) - { - condition_ != max_threads_; - } -}; - -<font color=red>/* Test <font color=#008888>Condition::operator</font>>=() - Each svc() method will decrement the condition variable and wait - until it is less than max_threads_. To do this correctly, we have - to be careful where we start the condition variable. - */</font> -class Test_ge : public Test -{ -public: - <font color=red>// For max_threads_ == 5, we will start the condition variable at </font> - <font color=red>// the value 9. When the "<font color=green>last</font>" thread decrements it, the value</font> - <font color=red>// will be 4 which satisfies the condition.</font> - Test_ge(void) - : Test(max_threads_*2-1) - { - ACE_DEBUG ((LM_INFO, "<font color=green>\n(%P|%t|%T)\tTesting condition_ >= %d\n</font>", max_threads_)); - } - - <font color=red>// Decrement by one...</font> - void modify(void) - { - --condition_; - } - - <font color=red>// while( value >= max_threads_ ) wait();</font> - void test(void) - { - condition_ >= max_threads_; - } -}; - -<font color=red>/* Test <font color=#008888>Condition::operator</font><=() - This time we will increment the condition until it is greater than - max_threads_. Again, we have to be careful where we start the - value and how we increment. - */</font> -class Test_le : public Test -{ -public: - <font color=red>// I'm starting the value at 1 so that if we increment by one in</font> - <font color=red>// each thread, the "<font color=green>last</font>" thread (of 5) will set the value to</font> - <font color=red>// 6. Since I actually increment by 2, we could start somewhat lower.</font> - Test_le(void) - : Test(1) - { - ACE_DEBUG ((LM_INFO, "<font color=green>\n(%P|%t|%T)\tTesting condition_ <= %d\n</font>", max_threads_)); - } - - <font color=red>// Try out <font color=#008888>Condition::operator</font>+=(int)</font> - <font color=red>// This will cause the third thread to satisfy the condition.</font> - void modify(void) - { - condition_ += 2; - } - - <font color=red>// while( value <= max_threads_ ) wait();</font> - void test(void) - { - condition_ <= max_threads_; - } -}; - -<font color=red>/* For our final test, we'll go after <font color=#008888>Condition::operator</font>=(Condition::Compare) - By deriving from <font color=#008888>Condition::Compare</font> we can perform any arbitrary - test on the value of the condition variable. - */</font> -class Test_fo : public Test -{ -public: - <font color=red>// We'll be using operator*=(int) to increment the condition</font> - <font color=red>// variable, so we need to start with a non-zero value.</font> - Test_fo(void) - : Test(1) - { - ACE_DEBUG ((LM_INFO, "<font color=green>\n(%P|%t|%T)\tTesting condition_ == FunctionObject\n</font>" )); - } - - <font color=red>// Double the value for each thread that we have.</font> - void modify(void) - { - condition_ *= 2; - } - - <font color=red>/* Derive our CompareFunction and provide the operator() that - performs our test. In this case, we'll compare the value to - the number 32. - */</font> - class CompareFunction : public <font color=#008888>Condition::Compare</font> - { - public: - <font color=red>// When this returns non-zero, the condition test operator</font> - <font color=red>// will unblock in each thread.</font> - int operator() ( <font color=#008888>Condition::value_t</font> _value ) - { - return _value == 32; - } - }; - - <font color=red>// Create the CompareFunction and wait for the condition variable </font> - <font color=red>// to reach the state we want.</font> - void test(void) - { - CompareFunction compare; - condition_ == compare; - } -}; - -<font color=red>/* In main() we just instantiate each of the four test objects that we - created. After open()ing each, we wait() for it's threads to exit. - */</font> -int main(int, char **) -{ - Test_ne test_ne; - test_ne.open(); - test_ne.wait(); - - Test_ge test_ge; - test_ge.open(); - test_ge.wait(); - - Test_le test_le; - test_le.open(); - test_le.wait(); - - Test_fo test_fo; - test_fo.open(); - test_fo.wait(); - - return(0); -} -</PRE> -<P><HR WIDTH="100%"> -<CENTER>[<A HREF="../online-tutorials.html">Tutorial Index</A>] [<A HREF="page05.html">Continue This Tutorial</A>]</CENTER> |