code: @SuppressWarnings("unchecked")
    public <T extends Entry> T get(long index) {
      Entry entry = buffer[offset(index)];
      return entry != null && entry.getIndex() == index ? (T) entry.acquire() : null;
    }
docs: Looks up an entry in the buffer.
  
  @param index The entry index.
  @param <T> The entry type.
  @return The entry or {@code null} if the entry is not present in the index.