$re = '/(?s).*class\s+\w+\s*<.*,.*,.*>.*{/U';
$str = 'class ClazzA<R extends A,
S extends B<T>, T extends C<T>,
U extends D, W extends E,
X extends F, Y extends G, Z extends H>
extends OtherClazz<S> implements I<T> {
public void method(Type<Q, R> x) {
// ... code ...
}
}
';
preg_match($re, $str, $matches, PREG_OFFSET_CAPTURE, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php