code: public Set entrySet() throws ObjectManagerException {
          return new AbstractSetView() {
              public long size() {
                  return size;
              }
  
              public boolean contains(Object object) throws ObjectManagerException {
                  if (object instanceof Map.Entry) {
                      Map.Entry entry = (Map.Entry) object;
                      Object v1 = get(entry.getKey()), v2 = entry.getValue();
                      return v1 == null ? v2 == null : v1.equals(v2);
                  }
                  return false;
              }
  
              public Iterator iterator() throws ObjectManagerException {
                  return makeTreeMapIterator(new AbstractMapEntry.Type() {
                      public Object get(AbstractMapEntry entry) {
                          return entry;
                      }
                  });
              }
          };
      }
docs: Answers a Set of the mappings contained in this TreeMap. Each element in
  the set is a Map.Entry. The set is backed by this TreeMap so changes to
  one are relected by the other. The set does not support adding.
  
  @return a Set of the mappings