code: public void populate() throws Exception {
          for (int i = 0; i < _initialCapacity; i++) {
              String str = "key." + i;
              byte[] key = str.getBytes();
              byte[] value = createDataForKey(str);
              _store.put(key, value);
          }
          _store.sync();
      }
docs: Populates the underlying data store.
  
  @throws Exception