OOP - PHP Klassen und Vererbung (extends) ...

class Mensch
{
    const ANZAHL_AUGEN = 2;




    public function gibAnzahlAugen()
    {
        echo 'Mensch hat '.self::ANZAHL_AUGEN.' Auge(n)<br>'; // 2
    }
}




class Mann extends Mensch
{
    const ANZAHL_AUGEN = 2;




    public function gibAnzahlAugen()
    {
        echo 'Mann hat '.self::ANZAHL_AUGEN.' Auge(n)<br>'; // 2
        echo 'sowie ein Mensch '.parent::ANZAHL_AUGEN.' Auge(n) hat<br>'; // 2
    }
}




class EinAuge extends Mann
{
    const ANZAHL_AUGEN = 1;




    public function gibAnzahlAugen()
    {
        echo 'EinAuge hat '.self::ANZAHL_AUGEN.' Auge(n)<br>'; // 1
        echo 'aber normalerweise hat ein Mann '.parent::ANZAHL_AUGEN.' Auge(n)<br>'; // 2
        echo 'sowie ein Mensch '.Mensch::ANZAHL_AUGEN.' Auge(n) hat<br>'; // 2
    }
}




$person = new EinAuge();
$person->gibAnzahlAugen();

class CallBack
{
    private static
        $ready,
        $callonready;




    final public static function is_ready($called_class=null)
    {
        $cc = ($called_class)
            ?$called_class
            :get_called_class();




        return (isset(self::$ready[$cc])and self::$ready[$cc] === true);
    }
    final public static function register($classname=null,$function,$para=null)
    {
        $cc = get_called_class();




        self::$callonready[$cc][] = array(
            'class' => $classname,
            'func' => $function,
            'para' => $para,
        );
        # if already ready -> call registered:
        if(self::is_ready($cc)){
            self::execRegistered($cc);
        }
        return;
    }
    final protected static function execRegistered($called_class=null)
    {
        $cc = ($called_class)
            ?$called_class
            :get_called_class();




        self::$ready[$cc] = true;




        if(isset(self::$callonready[$cc])and is_array(self::$callonready[$cc])and !empty(self::$callonready[$cc])){
            foreach(self::$callonready[$cc] as $key => $call){
                if($call['class']){
                    call_user_func_array(
                        array($call['class'],$call['func']),
                        ($call['para'])
                            ?array($call['para'])
                            :array()
                    );
                }else{
                    call_user_func(
                        $call['func'],
                        ($call['para'])
                            ?$call['para']
                            :array()
                    );
                }
                unset(self::$callonready[$cc][$key]);
            }
        }
        return;
    }
}




class Sql extends CallBack
{
    public static function connect()
    {
        # after connecting *whatEva*
        echo '<br>i am at '.__METHOD__.'(), just connected and gona execute possibly registered ... (this means i am ready now)';
        self::execRegistered();
        return;
    }
    public static function doSomething()
    {
        if(Something::is_ready() === true){
            echo '<br>i am at '.__METHOD__.'() and Something::is_ready() === true -- Something called me back!';
        }else{
            echo '<br>i am at '.__METHOD__.'() and tried to call Something. But Something::is_ready() !== true -- is not ready :(';
            Something::register(__CLASS__,__METHOD__,null);
            echo '<br>so i ('.__METHOD__.'()) just registered at class Something -- waiting for a call back!';
        }
        return;
    }
}




class Something extends CallBack
{
    public static function loadnMyOwnSh1t()
    {
        # after loading *whatEva*
        echo '<br>i am at '.__METHOD__.'(), loaded my sh1t and gona execute possibly registered ... (this means i am ready now)';
        self::execRegistered();
        return;
    }
    public static function printMeThatString($str=null)
    {
        if(Sql::is_ready() === true){
            echo '<br>i am at '.__METHOD__.'() and Sql::is_ready() === true -- Sql called me back!';
            echo '<br>by the way: i ('.__METHOD__.'()) got the parameter `'.$str.'` from Sql =)';
            self::loadnMyOwnSh1t();
        }else{
            echo '<br>i am at '.__METHOD__.'() and tried to call Sql. But Sql::is_ready() !== true -- is not ready :(';
            Sql::register(__CLASS__,__METHOD__,$str);
            echo '<br>so i ('.__METHOD__.'()) just registered at class Sql -- waiting for a call back!';
        }
        return;
    }
    public static function printMeThatArray($arr=null)
    {
        if(Sql::is_ready() === true){
            echo '<br>i am at '.__METHOD__.'() and Sql::is_ready() === true -- Sql called me back!';
            echo '<br>by the way: i ('.__METHOD__.'()) got the parameter `'.implode('`, `',$arr).'` from Sql =)';
        }else{
            echo '<br>i am at '.__METHOD__.'() and tried to call Sql. But Sql::is_ready() !== true -- is not ready :(';
            Sql::register(__CLASS__,__METHOD__,$arr);
            echo '<br>so i ('.__METHOD__.'()) just registered at class Sql -- waiting for a call back!';
        }
        return;
    }
}




Sql::doSomething();
echo '<hr>';
Something::printMeThatString('my parameter value');
echo '<hr>';
Something::printMeThatArray(array(0=>'1st string',1=>'2nd string'));
echo '<hr>';
Sql::connect();




/* OUTPUT:







i am at Sql::doSomething() and tried to call Something. But Something::is_ready() !== true -- is not ready :(
so i (Sql::doSomething()) just registered at class Something -- waiting for a call back!




i am at Something::printMeThatString() and tried to call Sql. But Sql::is_ready() !== true -- is not ready :(
so i (Something::printMeThatString()) just registered at class Sql -- waiting for a call back!




i am at Something::printMeThatArray() and tried to call Sql. But Sql::is_ready() !== true -- is not ready :(
so i (Something::printMeThatArray()) just registered at class Sql -- waiting for a call back!




i am at Sql::connect(), just connected and gona execute possibly registered ... (this means i am ready now)
i am at Something::printMeThatString() and Sql::is_ready() === true -- Sql called me back!
by the way: i (Something::printMeThatString()) got the parameter `my parameter value` from Sql =)
i am at Something::loadnMyOwnSh1t(), loaded my sh1t and gona execute possibly registered ... (this means i am ready now)
i am at Sql::doSomething() and Something::is_ready() === true -- Something called me back!
i am at Something::printMeThatArray() and Sql::is_ready() === true -- Sql called me back!
by the way: i (Something::printMeThatArray()) got the parameter `1st string`, `2nd string` from Sql =)




*/