public Key unmarshall(JsonUnmarshallerContext context) throws Exception {
    Key key = new Key();

    int originalDepth = context.getCurrentDepth();
    int targetDepth = originalDepth + 1;

    JsonToken token = context.currentToken;
    if (token == null) token = context.nextToken();

    while (true) {
      if (token == null) break;

      if (token == FIELD_NAME || token == START_OBJECT) {
        if (context.testExpression("HashKeyElement", targetDepth)) {
          context.nextToken();
          key.setHashKeyElement(AttributeValueJsonUnmarshaller.getInstance().unmarshall(context));
        }
        if (context.testExpression("RangeKeyElement", targetDepth)) {
          context.nextToken();
          key.setRangeKeyElement(AttributeValueJsonUnmarshaller.getInstance().unmarshall(context));
        }
      } else if (token == END_ARRAY || token == END_OBJECT) {
        if (context.getCurrentDepth() <= originalDepth) break;
      }
      token = context.nextToken();
    }

    return key;
  }
  @Test
  public void queryUpdate() {
    // Setup table with items
    KeySchema schema =
        new KeySchema(
            new KeySchemaElement()
                .withAttributeName("id")
                .withAttributeType(ScalarAttributeType.S));
    createTable(tableName, schema);

    Key key = new Key();
    key.setHashKeyElement(new AttributeValue().withS("1"));

    Map<String, AttributeValueUpdate> dynValues = new HashMap<String, AttributeValueUpdate>();
    dynValues.put(
        "count", new AttributeValueUpdate(new AttributeValue().withN("100"), AttributeAction.ADD));

    UpdateItemRequest update = new UpdateItemRequest(tableName, key, dynValues);

    getClient().updateItem(update);

    inProcessClient.save(PERSISTENCE_PATH);
    createNewInProcessClient().restore(PERSISTENCE_PATH);

    AttributeValue hashKey = new AttributeValue().withS("1");
    QueryRequest request = new QueryRequest(tableName, hashKey);
    QueryResult result = getClient().query(request);
    Assert.assertNotNull(result.getItems());
    Assert.assertNotSame(result.getItems().size(), 0);
    Map<String, AttributeValue> row = result.getItems().get(0);
    Assert.assertEquals(row.get("id"), hashKey);
    Assert.assertEquals(row.get("count").getN(), "100");
  }
  @Test
  public void conditionalDeleteOldFieldUpdateOnHit() {
    // Setup table with items
    KeySchema schema =
        new KeySchema(
            new KeySchemaElement()
                .withAttributeName("id")
                .withAttributeType(ScalarAttributeType.S));
    createTable(tableName, schema);

    Key key = new Key();
    key.setHashKeyElement(new AttributeValue().withS("1"));

    Map<String, AttributeValueUpdate> oldValues = new HashMap<String, AttributeValueUpdate>();
    oldValues.put(
        "count", new AttributeValueUpdate(new AttributeValue().withN("100"), AttributeAction.PUT));
    oldValues.put(
        "ids",
        new AttributeValueUpdate(new AttributeValue().withS("[er, er]"), AttributeAction.ADD));

    UpdateItemRequest update = new UpdateItemRequest(tableName, key, oldValues);

    getClient().updateItem(update);

    // conditional update
    HashMap<String, AttributeValueUpdate> newValues = new HashMap<String, AttributeValueUpdate>();
    newValues.put(
        "count", new AttributeValueUpdate(new AttributeValue().withN("102"), AttributeAction.PUT));
    newValues.put(
        "ids",
        new AttributeValueUpdate(new AttributeValue().withS("[er, er]"), AttributeAction.DELETE));

    HashMap<String, ExpectedAttributeValue> expectedValues =
        new HashMap<String, ExpectedAttributeValue>();
    expectedValues.put(
        "count", new ExpectedAttributeValue().withValue(new AttributeValue().withN("100")));

    update =
        new UpdateItemRequest()
            .withTableName(tableName)
            .withKey(key)
            .withAttributeUpdates(newValues)
            .withExpected(expectedValues);
    getClient().updateItem(update);

    inProcessClient.save(PERSISTENCE_PATH);
    createNewInProcessClient().restore(PERSISTENCE_PATH);

    AttributeValue hashKey = new AttributeValue().withS("1");
    QueryRequest request = new QueryRequest(tableName, hashKey);
    QueryResult result = getClient().query(request);
    Assert.assertNotNull(result.getItems());
    Assert.assertNotSame(result.getItems().size(), 0);
    Map<String, AttributeValue> row = result.getItems().get(0);
    Assert.assertEquals(row.get("id"), hashKey);
    Assert.assertEquals(row.get("count").getN(), "102");
    Assert.assertNull(row.get("ids"));
  }
  @Test
  public void conditionalUpdateOnMissing() {
    // Setup table with items
    KeySchema schema =
        new KeySchema(
            new KeySchemaElement()
                .withAttributeName("id")
                .withAttributeType(ScalarAttributeType.S));
    createTable(tableName, schema);

    Key key = new Key();
    key.setHashKeyElement(new AttributeValue().withS("1"));

    Map<String, AttributeValueUpdate> oldValues = new HashMap<String, AttributeValueUpdate>();
    oldValues.put(
        "count", new AttributeValueUpdate(new AttributeValue().withN("100"), AttributeAction.PUT));

    UpdateItemRequest update = new UpdateItemRequest(tableName, key, oldValues);

    getClient().updateItem(update);

    // conditional update
    HashMap<String, AttributeValueUpdate> newValues = new HashMap<String, AttributeValueUpdate>();
    newValues.put(
        "count", new AttributeValueUpdate(new AttributeValue().withN("102"), AttributeAction.PUT));

    HashMap<String, ExpectedAttributeValue> expectedValues =
        new HashMap<String, ExpectedAttributeValue>();
    expectedValues.put(
        "count", new ExpectedAttributeValue().withValue(new AttributeValue().withN("10")));

    update =
        new UpdateItemRequest()
            .withTableName(tableName)
            .withKey(key)
            .withAttributeUpdates(newValues)
            .withExpected(expectedValues);

    try {
      getClient().updateItem(update);

      inProcessClient.save(PERSISTENCE_PATH);
      createNewInProcessClient().restore(PERSISTENCE_PATH);
      Assert.fail("expecting conditional check exception");
    } catch (ConditionalCheckFailedException e) {
      // expect this exception
    }
  }
  public Request<BatchGetItemRequest> marshall(BatchGetItemRequest batchGetItemRequest) {
    if (batchGetItemRequest == null) {
      throw new AmazonClientException("Invalid argument passed to marshall(...)");
    }

    Request<BatchGetItemRequest> request =
        new DefaultRequest<BatchGetItemRequest>(batchGetItemRequest, "AmazonDynamoDB");
    String target = "DynamoDB_20111205.BatchGetItem";
    request.addHeader("X-Amz-Target", target);
    request.addHeader("Content-Type", "application/x-amz-json-1.0");

    request.setHttpMethod(HttpMethodName.POST);

    String uriResourcePath = "";

    uriResourcePath = uriResourcePath.replaceAll("//", "/");

    if (uriResourcePath.contains("?")) {
      String queryString = uriResourcePath.substring(uriResourcePath.indexOf("?") + 1);
      uriResourcePath = uriResourcePath.substring(0, uriResourcePath.indexOf("?"));

      for (String s : queryString.split("[;&]")) {
        String[] nameValuePair = s.split("=");
        if (nameValuePair.length == 2) {
          request.addParameter(nameValuePair[0], nameValuePair[1]);
        } else {
          request.addParameter(s, null);
        }
      }
    }

    request.setResourcePath(uriResourcePath);

    try {
      StringWriter stringWriter = new StringWriter();
      JSONWriter jsonWriter = new JSONWriter(stringWriter);

      jsonWriter.object();

      if (batchGetItemRequest.getRequestItems() != null) {
        jsonWriter.key("RequestItems");
        jsonWriter.object();
        for (Map.Entry<String, KeysAndAttributes> requestItemsListValue :
            batchGetItemRequest.getRequestItems().entrySet()) {
          if (requestItemsListValue.getValue() != null) {
            jsonWriter.key(requestItemsListValue.getKey());

            jsonWriter.object();

            java.util.List<Key> keysList = requestItemsListValue.getValue().getKeys();
            if (keysList != null && keysList.size() > 0) {

              jsonWriter.key("Keys");
              jsonWriter.array();

              for (Key keysListValue : keysList) {
                if (keysListValue != null) {
                  jsonWriter.object();
                  AttributeValue hashKeyElement = keysListValue.getHashKeyElement();
                  if (hashKeyElement != null) {

                    jsonWriter.key("HashKeyElement");
                    jsonWriter.object();

                    if (hashKeyElement.getS() != null) {
                      jsonWriter.key("S").value(hashKeyElement.getS());
                    }
                    if (hashKeyElement.getN() != null) {
                      jsonWriter.key("N").value(hashKeyElement.getN());
                    }
                    if (hashKeyElement.getB() != null) {
                      jsonWriter.key("B").value(hashKeyElement.getB());
                    }

                    java.util.List<String> sSList = hashKeyElement.getSS();
                    if (sSList != null && sSList.size() > 0) {

                      jsonWriter.key("SS");
                      jsonWriter.array();

                      for (String sSListValue : sSList) {
                        if (sSListValue != null) {
                          jsonWriter.value(sSListValue);
                        }
                      }
                      jsonWriter.endArray();
                    }

                    java.util.List<String> nSList = hashKeyElement.getNS();
                    if (nSList != null && nSList.size() > 0) {

                      jsonWriter.key("NS");
                      jsonWriter.array();

                      for (String nSListValue : nSList) {
                        if (nSListValue != null) {
                          jsonWriter.value(nSListValue);
                        }
                      }
                      jsonWriter.endArray();
                    }

                    java.util.List<java.nio.ByteBuffer> bSList = hashKeyElement.getBS();
                    if (bSList != null && bSList.size() > 0) {

                      jsonWriter.key("BS");
                      jsonWriter.array();

                      for (java.nio.ByteBuffer bSListValue : bSList) {
                        if (bSListValue != null) {
                          jsonWriter.value(bSListValue);
                        }
                      }
                      jsonWriter.endArray();
                    }
                    jsonWriter.endObject();
                  }
                  AttributeValue rangeKeyElement = keysListValue.getRangeKeyElement();
                  if (rangeKeyElement != null) {

                    jsonWriter.key("RangeKeyElement");
                    jsonWriter.object();

                    if (rangeKeyElement.getS() != null) {
                      jsonWriter.key("S").value(rangeKeyElement.getS());
                    }
                    if (rangeKeyElement.getN() != null) {
                      jsonWriter.key("N").value(rangeKeyElement.getN());
                    }
                    if (rangeKeyElement.getB() != null) {
                      jsonWriter.key("B").value(rangeKeyElement.getB());
                    }

                    java.util.List<String> sSList = rangeKeyElement.getSS();
                    if (sSList != null && sSList.size() > 0) {

                      jsonWriter.key("SS");
                      jsonWriter.array();

                      for (String sSListValue : sSList) {
                        if (sSListValue != null) {
                          jsonWriter.value(sSListValue);
                        }
                      }
                      jsonWriter.endArray();
                    }

                    java.util.List<String> nSList = rangeKeyElement.getNS();
                    if (nSList != null && nSList.size() > 0) {

                      jsonWriter.key("NS");
                      jsonWriter.array();

                      for (String nSListValue : nSList) {
                        if (nSListValue != null) {
                          jsonWriter.value(nSListValue);
                        }
                      }
                      jsonWriter.endArray();
                    }

                    java.util.List<java.nio.ByteBuffer> bSList = rangeKeyElement.getBS();
                    if (bSList != null && bSList.size() > 0) {

                      jsonWriter.key("BS");
                      jsonWriter.array();

                      for (java.nio.ByteBuffer bSListValue : bSList) {
                        if (bSListValue != null) {
                          jsonWriter.value(bSListValue);
                        }
                      }
                      jsonWriter.endArray();
                    }
                    jsonWriter.endObject();
                  }
                  jsonWriter.endObject();
                }
              }
              jsonWriter.endArray();
            }

            java.util.List<String> attributesToGetList =
                requestItemsListValue.getValue().getAttributesToGet();
            if (attributesToGetList != null && attributesToGetList.size() > 0) {

              jsonWriter.key("AttributesToGet");
              jsonWriter.array();

              for (String attributesToGetListValue : attributesToGetList) {
                if (attributesToGetListValue != null) {
                  jsonWriter.value(attributesToGetListValue);
                }
              }
              jsonWriter.endArray();
            }
            if (requestItemsListValue.getValue().isConsistentRead() != null) {
              jsonWriter
                  .key("ConsistentRead")
                  .value(requestItemsListValue.getValue().isConsistentRead());
            }
            jsonWriter.endObject();
          }
        }
        jsonWriter.endObject();
      }

      jsonWriter.endObject();

      String snippet = stringWriter.toString();
      byte[] content = snippet.getBytes("UTF-8");
      request.setContent(new StringInputStream(snippet));
      request.addHeader("Content-Length", Integer.toString(content.length));
    } catch (Throwable t) {
      throw new AmazonClientException("Unable to marshall request to JSON: " + t.getMessage(), t);
    }

    return request;
  }