package Foo;

import java.util.HashMap;

public class Bar {
   public static void main(String... args) {
      HashMap<String, HashMap<String, Integer>> map = new HashMap<String, HashMap<String, Integer>>();
      map.put("A", new HashMap<String, Integer>());
      map.get("A").put("A", 1);
      map.get("A").put("B", 2);
      map.put("B", new HashMap<String, Integer>());
      map.get("B").put("A", 4);
      map.get("B").put("B", 8);

      for(String k: map.get("B").keySet()) {
         System.out.println(k + " - " + map.get("B").get(k));
      }
   }
}