public function checkDirectories()
{
$notWritable = array();
foreach ($this->mustBeWritable as $directory) {
$fullPath = $this->basePath . '/' . $directory;
if (!is_writable($fullPath)) {
$notWritable[] = $fullPath;
}
}
if (count($notWritable) > 0) {
return $notWritable;
}
return true;
}