@Override
    public void handleNewPutEntry(StoreKey key, IndexValue putValue) {
      this.currentValue = putValue;
      this.originalPutValue = null;
      this.previousValue = null;
    }
Replace initial index in store with mock index which would throw specified exception when finding entries/keys.
@param exception the store exception to throw when finding entries or missing keys.
@throws StoreException
ambry-store/src/test/java/com/github/ambry/store/BlobStoreTest.java