@Override
    public void execute() {
        BatchGetItemResponse result
                = ddbClient.batchGetItem(BatchGetItemRequest.builder().requestItems(determineBatchItems()).build());

        HashMap<Object, Object> tmp = new HashMap<>();
        tmp.put(Ddb2Constants.BATCH_RESPONSE, result.responses());
        tmp.put(Ddb2Constants.UNPROCESSED_KEYS, result.unprocessedKeys());
        addToResults(tmp);
    }
@SuppressWarnings("unchecked")
    @Test
    public void execute() {
        Map<String, AttributeValue> key = new HashMap<>();
        key.put("1", AttributeValue.builder().s("Key_1").build());
        Map<String, AttributeValue> unprocessedKey = new HashMap<>();
        unprocessedKey.put("1", AttributeValue.builder().s("UNPROCESSED_KEY").build());
        Map<String, KeysAndAttributes> keysAndAttributesMap = new HashMap<>();
        KeysAndAttributes keysAndAttributes = KeysAndAttributes.builder().keys(key).build();
        keysAndAttributesMap.put("DOMAIN1", keysAndAttributes);
        exchange.getIn().setHeader(Ddb2Constants.BATCH_ITEMS, keysAndAttributesMap);

        command.execute();

        assertEquals(keysAndAttributesMap, ddbClient.batchGetItemRequest.requestItems());

        List<Map<String, AttributeValue>> batchResponse = (List<Map<String, AttributeValue>>) exchange.getIn()
                .getHeader(Ddb2Constants.BATCH_RESPONSE, Map.class).get("DOMAIN1");
        AttributeValue value = batchResponse.get(0).get("attrName");

        KeysAndAttributes unProcessedAttributes
                = (KeysAndAttributes) exchange.getIn().getHeader(Ddb2Constants.UNPROCESSED_KEYS, Map.class).get("DOMAIN1");
        Map<String, AttributeValue> next = unProcessedAttributes.keys().iterator().next();

        assertEquals(AttributeValue.builder().s("attrValue").build(), value);
        assertEquals(unprocessedKey, next);
    }