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Convert mongo Query to Java ArrayList<Bson>

I need help in converting below mongo query to an ArrayList so that I can execute the query in spring boot app. Having tough time to convert it in java using Aggregate classe's match, group, etc. method.
private List aggregateInspectionWorkOrders(ArrayList operations) {
MongoCollection mongoCollection = db().getCollection(Constants.DB.MyTable, InspectionWorkOrder.class);
return mongoCollection.aggregate(operations).into(new ArrayList<>());
}
db.mytable.aggregate([
{
$match: {
$and: [
{
deleted: { $eq: false }
},
{
status: {
$in: ['O', 'IP']
}
}
]
}
},
{
$group: {
_id: {
sub: '$sub',
pre: '$pre'
},
location: { $addToSet: { mile: '$mp'}}
}
},
{
$group: {
_id: {
sub: '$_id.sub'
},
location: {
$addToSet: {
pre: '$_id.pre',
from: {
$min: '$location.mp'
},
to: {
$max: '$location.mp'
}
}
}
}
},
{
$project: {
_id: 0,
sub: '$_id.sub',
location: '$location'
}
}
]).pretty()

DynamoDBMappingException: could not unconvert attribute, expected S in value

I am working on getting map type data stored in DynamoDB, the way I have tried so far:
use String getData() in my POJO, however, there is an issue that DynamoDBMappingException: could not unconvert attribute.
use Map<String, Object> getData() and annotated with #DynamoDBTypeConverted(converter = MapConverter.class) to retrieve the data, and also wrote a converter for it. This method also throws Exception DynamoDBMappingException: could not unconvert attribute, expected S in value.
So my question is:
is there a way to retrieve the standard JSON format data from DynamoDB by using mapper instead of DynamoJson without “N”, “S”, etc?
For instance:
"data": {
"cId":"777",
"cName":"NPR"
"isOwner":true
}
Once I get the standard JSON, I can use objectmapper to convert it to arbitrary data based on different use cases.
2. is it possible to use a map here? I found some folks create POJO for nested data, however, in my use case, the data fields vary from the different scenarios.
The converter I wrote:
public class MapConverter implements DynamoDBTypeConverter<String, Map> {
private final ObjectMapper objectMapper;
public MapConverter() {
objectMapper = new ObjectMapper();
objectMapper.configure(MapperFeature.ACCEPT_CASE_INSENSITIVE_PROPERTIES, true);
}
#Override
public String convert(final Map map) {
if (map == null) {
return null;
}
try {
return objectMapper.writeValueAsString(map);
} catch (JsonProcessingException e) {
log.error("Hit exception while trying to convert map. {}.", map, e);
return null;
}
}
#Override
public Map unconvert(String serializedMap) {
if (serializedMap == null) {
return null;
}
try {
return objectMapper.readValue(serializedMap, Map.class);
} catch (IOException e) {
log.error("Hit exception while trying to unconvert map. {}.", serializedMap, e);
return null;
}
}
}
The data in the DynamoDB is like this:
{
"data": {
"M": {
"cId": {
"S": "777"
},
"cName": {
"S": "NPR"
},
"isOwner": {
"BOOL": true
}
}
}
}
and it may also look like
"data": {
"M": {
"globalEntityId": {
"S": "234"
},
"providerMetadata": {
"L": [
{
"M": {
"proj.123": {
"M": {
"entityId": {
"S": "s:123"
}
}
},
"PA": {
"M": {
"entityId": {
"S": "p:123"
}
}
}
}
}
]
}
}
}

Getting this error whilt trying to parse JSON data W/System.err: org.json.JSONException: No value for customers

I am trying to retreive customer object from my rest api. I generated the api using spring data jpa. I have used volley to retrive the information from the api. I can't tell what i did wrong. As i am new to android i don't have much idea. can some one help me to parse the customer object from my Json api.
my api looks like this:
{
"_embedded": {
"customers": [
{
"firstName": "Alexander",
"lastName": "arnold",
"email": "trentarnold#liverpool.com",
"password": "cornertakenquickly",
"_links": {
"self": {
"href": "http://localhost:8080/api/customers/1"
},
"customer": {
"href": "http://localhost:8080/api/customers/1"
}
}
},
{
"firstName": "test",
"lastName": "tester",
"email": "dulalsujan911#gmail.com",
"password": "12345678",
"_links": {
"self": {
"href": "http://localhost:8080/api/customers/2"
},
"customer": {
"href": "http://localhost:8080/api/customers/2"
}
}
}
]
},
"_links": {
"self": {
"href": "http://localhost:8080/api/customers{?page,size,sort}",
"templated": true
},
"profile": {
"href": "http://localhost:8080/api/profile/customers"
}
},
"page": {
"size": 20,
"totalElements": 2,
"totalPages": 1,
"number": 0
}
}
my code looks like this i am using volley :
// connects to the api and stores the retrived JSON values in the respective list
public void connectToApi(){
// initialize lists
emailList = new ArrayList<>();
passwordList = new ArrayList<>();
final String BASE_URL ="http://192.168.1.67:8080/api/customers";
// final String BASE_URL ="http://10.0.2.2:8080/api/customers";
// creating a request ques for HTTP request
RequestQueue requestQueue = Volley.newRequestQueue(this);
// Setting HTTP GET request to retrieve the data from the SERVER
JsonObjectRequest objectRequest = new JsonObjectRequest(Request.Method.GET,BASE_URL
,null
, new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
try {
JSONArray jsonArray = response.getJSONArray("customers");
for(int i=0; i<jsonArray.length();i++){
JSONObject customer = jsonArray.getJSONObject(i);
emailList.add(customer.getString("email"));
passwordList.add(customer.getString("password"));
}
} catch (Exception e) {
e.printStackTrace();
}
}
} , new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Log.e("REST error",error.toString() );
}
}
);
requestQueue.add(objectRequest);
}

Do this :
#Override
public void onResponse(JSONObject response) {
try {
JSONObject json = new JSONObject(response);
JSONObject json_embedded = json.getJSONObject("_embedded");// need to access JSONObject("_embedded")
JSONArray jsonArray = json_embedded.getJSONArray("customers"); // then get JSONARRAY
for(int i=0; i<jsonArray.length();i++){
JSONObject customer = jsonArray.getJSONObject(i);
emailList.add(customer.getString("email"));
passwordList.add(customer.getString("password"));
}
} catch (Exception e) {
e.printStackTrace();
}
}
NOTE : your json array (customers) is in _embedded that's why
it is showing exception.

You need to access first to _embedded object.
try {
JSONObject embedded = response.getJSONObject("_embedded");
JSONArray jsonArray = embedded.getJSONArray("customers");
for(int i=0; i<jsonArray.length();i++){
JSONObject customer = jsonArray.getJSONObject(i);
emailList.add(customer.getString("email"));
passwordList.add(customer.getString("password"));
}
} catch (Exception e) {
e.printStackTrace();
}

querying on field missing from some document in elasticsearch

I have a special need where in I need to query elastic search for a field say F1.
F1 is not there in all documents . My search should be for missing F1 documents and F1 with some value.
F1 is missing or F1 = 'A1'
I am not sure if this is possible in elastic search. Here is my query and I know that is not right query. Would appreciate somebody could correct it or the Java program.
{
"query": {
"filtered": {
"query": {
"match_all": {}
},
"filter": {
"bool": {
"must": [
{
"bool": {
"should": {
"terms": {
"F1": [
"Some Value"
]
}
}
}
},
{
"missing": {
"field": "F1"
}
}
]
}
}
}
}
}
This is my java code building the query.
public QueryBuilder getQueryBuilder() {
QueryBuilder qb;
//what do we want to return if there is no request? Nothing or all.
if (filters == null || filters.isEmpty()) {
qb = QueryBuilders.matchAllQuery();
} //build our filtered query using given filters in our request
else {
Set<String> keys = filters.keySet();
BoolFilterBuilder boolFilterBuilder = FilterBuilders.boolFilter();
for (String key : keys) {
Set<Object> values = filters.get(key);
if (values == null || values.toString().isEmpty()) {
continue; //Ignore nothing to do.
}
if (key.equalsIgnoreCase(Constants.MISSING_FILTER)) {
Iterator i = values.iterator();
while (i.hasNext()) {
boolFilterBuilder.must(FilterBuilders.missingFilter((String) i.next()));
}
} else {
boolFilterBuilder.must(buildShouldQuery(key, values));
}
}
qb = QueryBuilders.filteredQuery(createSearchQueryBuilder(), boolFilterBuilder);
}
return qb;
}

Try whit this.
{
"query": {
"filtered": {
"query": {
"match_all": {}
},
"filter": {
"bool": {
"should": [
{ "terms": { "F1": ["Some Value"] },
{ "missing": { "field": "F1" } }
]
}
}
}
}
}

extract url from facebook FQL

I am stuck here and would like to extract using java the second link of the facebook query below
{
"data": [
{
"attachment": {
"media": [
{
"photo": {
"images": [
{
"src": "https://fbcdn-photos-h-a.akamaihd.net/hphotos-ak-prn2/1508634_699393523428883_996610253_s.png"
},
{
"src": "https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-prn2/s720x720/1508634_699393523428883_996610253_n.png"
}
]
}
}
]
}
}
]
}
my code below, is obviously not working
try
{
List<JsonObject> queryResults = facebookClient.executeFqlQuery(query, JsonObject.class);
if(!queryResults.isEmpty())
{
JsonObject facebookPosturl_J = queryResults.get(0);
facebook_post = facebookPosturl_J.getString("src");
}
}
catch (Exception e){logger.warn("Unexpected error", e);}

Try calling:
facebookPosturl_J.getJsonArray("data").getJsonObject(0).getJsonObject("attachment").getJsonArray("media").getJsonObject(0).getJsonObject("photo").getJsonArray("images").getJsonObject(1).getString("src")