diff options
Diffstat (limited to 'docs/tutorials/016/page03.html')
| -rw-r--r-- | docs/tutorials/016/page03.html | 225 |
1 files changed, 0 insertions, 225 deletions
diff --git a/docs/tutorials/016/page03.html b/docs/tutorials/016/page03.html deleted file mode 100644 index 55bbb273f89..00000000000 --- a/docs/tutorials/016/page03.html +++ /dev/null @@ -1,225 +0,0 @@ -<!-- $Id$ --> -<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%"> -Ok, now we'll take a look at the definition of the class. You already -know how to use an ACE_Condition & it's not really that difficult. -Still, imagine how much more cluttered your code would be if it had to -include the mess I've got below! -<HR> -<PRE> - -<font color=red>// $Id$</font> - -<font color=red>// Get or declaration</font> -<font color=blue>#include</font> "<font color=green>Condition_i.h</font>" - -<font color=red>/* Initialize the condition variable and create the condition mutex. - Since I don't have any guarantees on the order of member variable - initialization, I have to new the condition mutex instead of - simply constructing it. - */</font> -<font color=#008888>Condition::Condition</font>(value_t _value) - : value_(_value) -{ - condition_ = new condition_t( this->mutex() ); -} - -<font color=#008888>Condition::~Condition</font>(void) -{ - <font color=red>// Be sure we don't have a memeory leak</font> - delete condition_; -} - -<font color=red>/* The cast operator is the easiest way to return a copy of the value - to clients of the class. It also allows us to use a private method - for getting a reference to the value when we need to modify it. - */</font> -<font color=#008888>Condition::operator</font> Condition::value_t (void) -{ - <font color=red>// Place a guard around the variable so that it won't change as</font> - <font color=red>// we're copying it back to the client.</font> - guard_t guard(mutex_); - return value(); -} - -<font color=red>/* Traditional prefix increment operator. - We place a guard around the operation so that we don't collide with - any other threads. After the modification, we broadcast() a - condition change to any waiting threads. You can also use signal() - but that will only tell one thread about the change. If that - thread, in turn, invokes signal() then all threads will eventually - find out. I just thought it would be easier to use broadcast() and - be done with it. - */</font> -Condition & <font color=#008888>Condition::operator</font>++ (void) -{ - guard_t guard(mutex_); - - ++value(); - - condition().broadcast(); - - return *this; -} - -<font color=red>/* The remaining operators all follow the same pattern that we have - above. They only differ in the modification they make to the value(). - */</font> - -Condition & <font color=#008888>Condition::operator</font>-- (void) -{ - guard_t guard(mutex_); - - --value(); - - condition().broadcast(); - - return *this; -} - -Condition & <font color=#008888>Condition::operator</font>+= (int _inc) -{ - guard_t guard(mutex_); - - value() += _inc; - - condition().broadcast(); - - return *this; -} - -Condition & <font color=#008888>Condition::operator</font>-= (int _inc) -{ - guard_t guard(mutex_); - - value() -= _inc; - - condition().broadcast(); - - return *this; -} - -Condition & <font color=#008888>Condition::operator</font>*= (int _inc) -{ - guard_t guard(mutex_); - - value() *= _inc; - - condition().broadcast(); - - return *this; -} - -Condition & <font color=#008888>Condition::operator</font>/= (int _inc) -{ - guard_t guard(mutex_); - - value() /= _inc; - - condition().broadcast(); - - return *this; -} - -Condition & <font color=#008888>Condition::operator</font>%= (int _inc) -{ - guard_t guard(mutex_); - - value() %= _inc; - - condition().broadcast(); - - return *this; -} - -Condition & <font color=#008888>Condition::operator</font>= ( value_t _value ) -{ - guard_t guard(mutex_); - - value() = _value; - - condition().broadcast(); - - return *this; -} - -<font color=red>/* Now we get into the comparison area. - Each one follows the pattern we've already established for - waiters. - */</font> - -<font color=red>/* - We begin with an equality operator that expects a function object. - In the while() test we pass a copy of the value to the function - object for evaluation. The object can then do any comparision it - wants to check for a desired condition. When the function object - returns non-zero, the condition is met and we leave. - */</font> -int <font color=#008888>Condition::operator</font>== ( Condition::Compare & _compare ) -{ - guard_t guard(mutex_); - - while( ! _compare(this->value()) ) - condition().wait(); - - return 0; -} - -<font color=red>// As long as the variable equals _value, we wait...</font> -int <font color=#008888>Condition::operator</font>== ( value_t _value ) -{ - guard_t guard(mutex_); - - while( value() == _value ) - condition().wait(); - - return 0; -} - -<font color=red>// As long as the variable is not equal to _value, we wait...</font> -int <font color=#008888>Condition::operator</font>!= ( value_t _value ) -{ - guard_t guard(mutex_); - - while( value() != _value ) - condition().wait(); - - return 0; -} - -<font color=red>// As long as the variable is less than or equal to _value, we wait...</font> -int <font color=#008888>Condition::operator</font><= ( value_t _value ) -{ - guard_t guard(mutex_); - - while( value() <= _value ) - condition().wait(); - - return 0; -} - -<font color=red>// As long as the variable is greater than or equal to _value, we wait...</font> -int <font color=#008888>Condition::operator</font>>= ( value_t _value ) -{ - guard_t guard(mutex_); - - while( value() >= _value ) - condition().wait(); - - return 0; -} -</PRE> -<P><HR WIDTH="100%"> -<CENTER>[<A HREF="../online-tutorials.html">Tutorial Index</A>] [<A HREF="page04.html">Continue This Tutorial</A>]</CENTER> |