@Override
    protected StoreKey getConvertedKey(StoreKey storeKey, boolean isKeyPresent, StoreKey cachedMapping) {
      if (exception != null) {
        throw new IllegalStateException(exception);
      } else if (!isKeyPresent) {
        throw new IllegalStateException(storeKey + " has not been converted");
      }
      return cachedMapping;
    }
Set conversionMap for reference.
@param conversionMap used by this {@link MockStoreKeyConverter} instance
ambry-test-utils/src/main/java/com/github/ambry/store/MockStoreKeyConverterFactory.java