How to swap arrayMap values and keys in Java

Question

I\'m having a bit of trouble reversing a given map and storing its reversed keys and values into another map. I have a method prototype as follows:

public st         


        

Answer 1

Pseudocode, but close to real. Just use a Multimap.

Multimap ret = Multimaps.newSetMultimap();
for (Entry> entry : graph) {
  for(String neighbor : entry.getValue()) {
    ret.addTo(neighbor, entry.getKey());
  }
}