protected function isValidFile($file)
    {
        if (!is_file($file) || !is_readable($file)) {
            throw new \InvalidArgumentException(sprintf(
                    'File "%s" Is Not Readable', (string) $file
            ));
        }
    }
protected function isValidFile($file)
    {
        if (!is_file($file) || !is_readable($file)) {
            throw new \InvalidArgumentException(sprintf(
                    'File "%s" Is Not Readable', (string) $file
            ));
        }
    }
protected function isValidFile ( $ file ) { if ( ! is_file ( $ file ) || ! is_readable ( $ file ) ) { throw new \ InvalidArgumentException ( sprintf ( 'File "%s" Is Not Readable' , ( string ) $ file ) ) ; } }
Check if the given string represents a path to a readable file

@param string $file

@throws \InvalidArgumentException
Check if the given string represents a path to a readable file