Getting all objects with same key from a MultiValueMap

I have a MultiValueMap<Integer, Path> from which I am trying to get [print for the purpose of this question] out all the paths which were put in the map using the same key.

This is my current solution:

MultiValueMap<Integer, Path> duplicates = duplicateFinder.getDuplicates();

for (Map.Entry<Integer, Object> entry: duplicates.entrySet()) {
  final Integer key = entry.getKey();
  final Object obj = entry.getValue();
  for (Object o: (LinkedList)((ArrayList)entry.getValue()).get(0))
    System.out.println(o);
  System.out.println();
}

I feel my solution is dangerous (casting and magic number 0) and would like to avoid it. How can I achieve the desired result in a more readable/safe manner?

The entry set seems to be declared with an unfortunate signature. But you could iterate over the keys instead, and call getCollection for each:

for (Integer key : duplicates.keySet()) {
    Collection<Path> paths = duplicates.getCollection(key);
    System.out.println("Paths for " + key);
    for (Path path : paths) {
        System.out.println("  " + path);
    }
    System.out.println();
}

(Note that Guava's Multimap would allow you to use duplicates.asMap().entrySet() instead, and each entry would have a Collection<V> as a value...)