php: autoload exception handling.

Question

Hello again, I'm extending my previous question (Handling exceptions within exception handle) to address my bad coding practice. I'm trying to delegate autoload errors to a exception handler.

<?php
function __autoload($class_name) {
    $file = $class_name.'.php';
    try {
        if (file_exists($file)) {
            include $file;  
        }else{
            throw new loadException("File $file is missing");
        }
        if(!class_exists($class_name,false)){
            throw new loadException("Class $class_name missing in $file");
        }
    }catch(loadException $e){
        header("HTTP/1.0 500 Internal Server Error");
        $e->loadErrorPage('500');
        exit;
    }
    return true;
}
class loadException extends Exception {
    public function __toString()
    {
        return get_class($this) . " in {$this->file}({$this->line})".PHP_EOL
                                ."'{$this->message}'".PHP_EOL
                                . "{$this->getTraceAsString()}";
    }
    public function loadErrorPage($code){
        try {
            $page = new pageClass();
            echo $page->showPage($code);
        }catch(Exception $e){
            echo 'fatal error: ', $code;
        }
    }
}



$test = new testClass();
?>

the above script is supposed to load a 404 page if the testClass.php file is missing, and it works fine, UNLESS the pageClass.php file is missing as well, in which case I see a

"Fatal error: Class 'pageClass' not found in D:\xampp\htdocs\Test\PHP\errorhandle\index.php on line 29" instead of the "fatal error: 500" message

I do not want to add a try/catch block to each and every class autoload (object creation), so i tried this.

What is the proper way of handling this?

Answer 1

Have you tried checking for pageClass early on in the process, since it seems to be necessary even to get the error page out? If it doesn't exist, and if you don't want to write the 404 page w/o any objects (e.g. just HTML), bombing out of execution where that class doesn't exist would seem to be a good path.

Hope that helps.

Thanks, Joe