Question

Let’s say were using custom extensions of the Exception class to handle custom exceptions,
like this for example:

$testObject = new testClass();

and a autoload like this:

function __autoload($class_name) {
    $file = $class_name.'.php';
    if (file_exists($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");
    }
    return true;
}

try {
    $testObject = new testClass();
}catch(loadException $e){
    exit('<pre>'.$e.'</pre>');
}

the file testClass.php does not exist, so a loadException is called with the message:
File testClass.php is missing. (and all the other details…line number etc)

all was fine, until i decided to hide all the errors and instead display a 404 page (or a 500 page…), so naturally i thought to add a loadErrorPage function.

class loadException {

...

    function loadErrorPage($code){
        $page = new pageClass();
        echo $page->showPage($code);
    }
}

...

try {
    $testObject = new testClass();
}catch(loadException $e){
    $e->loadErrorPage(500);
}

but this has the obvious problem that if the testClass.php AND pageClass.php files are missing, then a fatal error is shown instead of the preferred 404 page.

I’m confused :S
How do I elegantly handle this exception within a exception handle?

Answer 1

If class pageClass does not exist and cannot be loaded by your autloader $page = new pageClass(); in your method loadErrorPage() will cause another exception. You’d have to catch this exception and then do something without that class.

function loadErrorPage($code){
  try {
    $page = new pageClass();
    echo $page->showPage($code);
  }
  catch(Exception $e) {
    // header(...500);
    echo 'fatal error: ', $code;
  }
}