class EHCachingExchangeSource extends AbstractEHCachingSourceWithExternalBundle<Exchange, ExchangeSource> implements ExchangeSource {

  @Override
  public Exchange getSingle(final ExternalId identifier) {
    final Exchange result = getUnderlying().getSingle(identifier);
    cacheItem(result);
    return result;
  }

  public  EHCachingExchangeSource(final ExchangeSource underlying, final CacheManager cacheManager);

}