hoge999.php

<?php

abstract class Foo {
    abstract public function func(int $y);
}

class Bar extends Foo {
    public function func(int $y) {
        return 1;
    }
}

class Baz extends Bar {
    public function func(int $y) {
    }
}

$cl = new ReflectionClass(new Baz());
$methods = $cl->getMethods();
foreach ($methods as $mt) {
    printf("method: class=%s, name=%s\n", $mt->getDeclaringClass()->getName(), $mt->getName());
    $proto = $mt->getPrototype();
    printf("prototype: class=%s name=%s\n", $proto->getDeclaringClass()->getName(), $proto->getName());
}