code: public Map.Entry<K, V> getEntry(Object key) {
      EntryImpl<K, V> entry = _entries[keyHash(key) & _mask];
      while (entry != null) {
        if (key.equals(entry._key)) { return entry; }
        entry = entry._next;
      }
      return null;
    }
docs: Returns the entry with the specified key.
  
  @param key the key whose associated entry is to be returned.
  @return the entry for the specified key or <code>null</code> if none.