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Use geojson polygon in geoShapeQuery in ElasticSearch 7.4 java client

Does anyone have a code sample using geojson shape in ElasticSearch 7.x shape query?
It works when I build the shape using ES builders, however I need to use geojson passed in (see below), which likely needs parsing of geojson into ES shape:
{"type":"Polygon","coordinates":[[[-82.30957031249999,26.657277674217585],[-81.7767333984375,25.84686509678058],[-80.90057373046875,24.986058021167594],[-80.25238037109375,25.16517336866393],[-79.97222900390625,26.08885491679362],[-79.771728515625,26.76277822801415],[-80.2606201171875,27.25707120788274],[-80.83740234375,27.332735136859146],[-81.529541015625,27.166695222253114],[-82.30957031249999,26.657277674217585]]]}

I've been struggling with this as well though I actually wanted to feed a JTS Geometry directly to a query. The solution I came up with was to use WrapperQueryBuilder to write the query in JSON:
import org.elasticsearch.common.geo.ShapeRelation;
import org.elasticsearch.index.query.QueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
...
String queryName = "...";
String geoJson = "...";
QueryBuilder geoShapeQuery = QueryBuilders.wrapperQuery(
String.format(
"{ \"geo_shape\": { \"%s\": { \"shape\": %s, \"relation\": \"%s\" } } }",
queryName,
geoJson,
ShapeRelation.INTERSECTS.getRelationName()));

My query shapes are simple polygons, so I ended up converting it to an array of points and creating a polygon out of these:
if (null != shape) {
JSONObject jsonShape = new JSONObject(shape);
JSONArray coords = jsonShape.getJSONArray("coordinates");
CoordinatesBuilder cb = new CoordinatesBuilder();
for (Object coord: coords.getJSONArray(0)) {
JSONArray c = new JSONArray(coord.toString());
cb.coordinate((Double)c.get(0), (Double)c.get(1));
}
PolygonBuilder pb = new PolygonBuilder(cb);
gsqb = QueryBuilders.geoShapeQuery("FOOTPRINT", pb.buildGeometry());
}

(JAVA, Elasticsearch) How can I get fields from SearchResponse?

I just wonder how I get fields from SearchResponse which is result of my query.
Below is my query:
{"size":99,"timeout":"10s","query":{"bool":{"filter":[{"bool":{"must":[{"range":{"LOG_GEN_TIME":{"from":"2018-11-01 12:00:01+09:00","to":"2018-11-01 23:59:59+09:00","include_lower":true,"include_upper":true,"boost":1.0}}},{"wrapper":{"query":"eyAiYm9vbCIgOiB7ICJtdXN0IiA6IFsgeyAidGVybSIgOiB7ICJBU1NFVF9JUCIgOiAiMTAuMTExLjI1Mi4xNiIgfSB9LCB7ICJ0ZXJtIiA6IHsgIkFDVElPTl9UWVBFX0NEIiA6ICIyIiB9IH0sIHsgInRlcm0iIDogeyAiRFNUX1BPUlQiIDogIjgwIiB9IH0gXSB9IH0="}}],"adjust_pure_negative":true,"boost":1.0}}],"adjust_pure_negative":true,"boost":1.0}},"_source":{"includes":["LOG_GEN_TIME","LOG_NO","ASSET_NO"],"excludes":[]},"sort":[{"LOG_GEN_TIME":{"order":"desc"}},{"LOG_NO":{"order":"desc"}}]}
and when I query this, like below:
SearchResponse searchResponse = request.get();
I got right result:
{
"took":1071,
"timed_out":false,
"_shards":{
"total":14,
"successful":14,
"skipped":0,
"failed":0
},
"_clusters":{
"total":0,
"successful":0,
"skipped":0
},
"hits":{
"total":2,
"max_score":null,
"hits":[
{
"_index":"log_20181101",
"_type":"SEC",
"_id":"1197132746951492963",
"_score":null,
"_source":{
"ASSET_NO":1,
"LOG_NO":1197132746951492963,
"LOG_GEN_TIME":"2018-11-01 09:46:28+09:00"
},
"sort":[
1541033188000,
1197132746951492963
]
},
{
"_index":"log_20181101",
"_type":"SEC",
"_id":"1197132746951492963",
"_score":null,
"_source":{
"ASSET_NO":2,
"LOG_NO":1197337264704454700,
"LOG_GEN_TIME":"2018-11-01 23:00:06+09:00"
},
"sort":[
1541080806000,
1197337264704454700
]
}
]
}
}
To use this result, I need to map this by field and value.
I think there's a way to map the field and value to the 'fields' parameter so that we could use it nicely, but I cannot find.
I hope I can use the result like this way:
SearchHit hit = ...
Map<String, SearchHitField> fields = hit.getFields();
String logNo = fields.get("LOG_NO").value();
And It seems like this is the common way to use..
Or am I misunderstanding something? Tell me other way if there's better way, please.
Any comment would be appreciated. Thanks.

I'm not clear what client you are using to query elastic. If you are using elasticsearch high level rest client then you can loop through hits and to get source you can use hit.getSourceAsMap() to get the key value of fields.
For your comment:
Firstly create a POJO class which corresponds to _source (i.e. index properties; the way data is store in elastic)
The use hit.getSourceAsString() to get _source in json format.
Use jackson ObjectMapper to map json to your pojo
Assuming you created a POJO class AssetLog
SearchHit[] searchHits = searchResponse.getHits().getHits();
for (SearchHit searchHit : searchHits) {
String hitJson = searchHit.getSourceAsString();
ObjectMapper objectMapper = new ObjectMapper();
AssetLog source = objectMapper.readValue(hitJson, AssetLog.class);
//Store source to map/array
}
Hope this helps.

Call java generics on nativescript to convert JSON to HashMap

I'm building an Nativesctipt app for Android that uses Firebase as backend and I'm using the native Firebase Android library v2.4.0
I can insert objects in Firebase just fine using the following {N} Javascript syntax
var user = new java.util.HashMap();
user.put("name", viewModel.get("name"));
user.put("lastName", viewModel.get("lastName");
var address = new java.util.HashMap();
address.put("address", viewModel.get("address");
address.put("number", viewModel.get("number");
address.put("city", viewModel.get("city");
user.put("address", address);
ref = new Firebase("https://my-firebase-app-url/users");
refUser = ref.child(viewModel.get("username"));
refUser.setValue(user);
The problem with this is that I have to manually convert every javascript object into a java hashSet (and back) and I wanted to do it using a JSON to HashMap library so I have imported the java Jackson library into my {N} app.
According to this site here's the way to convert a JSON to a HashMap in Java using Jackson:
ObjectMapper mapper = new ObjectMapper();
String json = "{\"name\":\"mkyong\", \"age\":29}";
Map<String, Object> map = new HashMap<String, Object>();
// convert JSON string to Map
map = mapper.readValue(json, new TypeReference<Map<String, String>>(){});
I'm looking for a way to translate that into a {N} Javascript code that will do it for me but I'm unable to use generics notation in {N} Javascript. Does anybody know how I could do it? I have tried some ways but all of them crashed the application. Here's an {N} Javascript snippet does not work:
var ObjectMapper = com.fasterxml.jackson.databind.ObjectMapper;
var TypeReference = com.fasterxml.jackson.core.type.TypeReference;
var mapper = new ObjectMapper();
var map = mapper.readValue(JSON.stringify(user), new TypeReference());
refUser.setValue(map);
Any help is greatly appreciated.

Basic use of JSONPath in Java

I have JSON as a string and a JSONPath as a string. I'd like to query the JSON with the JSON path, getting the resulting JSON as a string.
I gather that Jayway's json-path is the standard. The online API, however, doesn't have have much relation to the actual library you get from Maven. GrepCode's version roughly matches up though.
It seems like I ought to be able to do:
String originalJson; //these are initialized to actual data
String jsonPath;
String queriedJson = JsonPath.<String>read(originalJson, jsonPath);
The problem is that read returns whatever it feels most appropriate based on what the JSONPath actually finds (e.g. a List<Object>, String, double, etc.), thus my code throws an exception for certain queries. It seems pretty reasonable to assume that there'd be some way to query JSON and get JSON back; any suggestions?

Java JsonPath API found at jayway JsonPath might have changed a little since all the above answers/comments. Documentation too. Just follow the above link and read that README.md, it contains some very clear usage documentation IMO.
Basically, as of current latest version 2.2.0 of the library, there are a few different ways of achieving what's been requested here, such as:
Pattern:
--------
String json = "{...your JSON here...}";
String jsonPathExpression = "$...your jsonPath expression here...";
J requestedClass = JsonPath.parse(json).read(jsonPathExpression, YouRequestedClass.class);
Example:
--------
// For better readability: {"store": { "books": [ {"author": "Stephen King", "title": "IT"}, {"author": "Agatha Christie", "title": "The ABC Murders"} ] } }
String json = "{\"store\": { \"books\": [ {\"author\": \"Stephen King\", \"title\": \"IT\"}, {\"author\": \"Agatha Christie\", \"title\": \"The ABC Murders\"} ] } }";
String jsonPathExpression = "$.store.books[?(#.title=='IT')]";
JsonNode jsonNode = JsonPath.parse(json).read(jsonPathExpression, JsonNode.class);
And for reference, calling 'JsonPath.parse(..)' will return an object of class 'JsonContent' implementing some interfaces such as 'ReadContext', which contains several different 'read(..)' operations, such as the one demonstrated above:
/**
* Reads the given path from this context
*
* #param path path to apply
* #param type expected return type (will try to map)
* #param <T>
* #return result
*/
<T> T read(JsonPath path, Class<T> type);
Hope this help anyone.

There definitely exists a way to query Json and get Json back using JsonPath.
See example below:
String jsonString = "{\"delivery_codes\": [{\"postal_code\": {\"district\": \"Ghaziabad\", \"pin\": 201001, \"pre_paid\": \"Y\", \"cash\": \"Y\", \"pickup\": \"Y\", \"repl\": \"N\", \"cod\": \"Y\", \"is_oda\": \"N\", \"sort_code\": \"GB\", \"state_code\": \"UP\"}}]}";
String jsonExp = "$.delivery_codes";
JsonNode pincodes = JsonPath.read(jsonExp, jsonString, JsonNode.class);
System.out.println("pincodesJson : "+pincodes);
The output of the above will be inner Json.
[{"postal_code":{"district":"Ghaziabad","pin":201001,"pre_paid":"Y","cash":"Y","pickup":"Y","repl":"N","cod":"Y","is_oda":"N","sort_code":"GB","state_code":"UP"}}]
Now each individual name/value pairs can be parsed by iterating the List (JsonNode) we got above.
for(int i = 0; i< pincodes.size();i++){
JsonNode node = pincodes.get(i);
String pin = JsonPath.read("$.postal_code.pin", node, String.class);
String district = JsonPath.read("$.postal_code.district", node, String.class);
System.out.println("pin :: " + pin + " district :: " + district );
}
The output will be:
pin :: 201001 district :: Ghaziabad
Depending upon the Json you are trying to parse, you can decide whether to fetch a List or just a single String/Long value.
Hope it helps in solving your problem.

For those of you wondering why some of these years-old answers aren't working, you can learn a lot from the test cases.
As of September 2018, here's how you can get Jackson JsonNode results:
Configuration jacksonConfig = Configuration.builder()
.mappingProvider( new JacksonMappingProvider() )
.jsonProvider( new JacksonJsonProvider() )
.build();
JsonNode node = JsonPath.using( jacksonConfig ).parse(jsonString);

//If you have a json object already no need to initiate the jsonObject
JSONObject jsonObject = new JSONObject();
String jsonString = jsonObject.toString();
String path = "$.rootObject.childObject"
//Only returning the child object
JSONObject j = JsonPath.read(jsonString, path);
//Returning the array of string type from the child object. E.g
//{"root": "child":[x, y, z]}
List<String> values = sonPath.read(jsonString, path);

Check out the jpath API. It's xpath equivalent for JSON Data. You can read data by providing the jpath which will traverse the JSON data and return the requested value.
This Java class is the implementation as well as it has example codes on how to call the APIs.
https://github.com/satyapaul/jpath/blob/master/JSONDataReader.java
Readme -
https://github.com/satyapaul/jpath/blob/master/README.md

Serialize Pojos to JSON using new standard javax.json

I like the idea of having a standard for JSON serialization in Java, javax.json is a great step forward you can do an object graph like this:
JsonObject jsonObject3 =
Json.createObjectBuilder()
.add("name", "Ersin")
.add("surname", "Çetinkaya")
.add("age", 25)
.add("address",
Json.createObjectBuilder()
.add("city", "Bursa")
.add("country", "Türkiye")
.add("zipCode", "33444"))
.add("phones",
Json.createArrayBuilder()
.add("234234242")
.add("345345354"))
.build();
That's it, but how can I serialize a pojo or simple Java object(like a Map) direct to JSON?, something like I do in Gson:
Person person = new Person();
String jsonStr = new Gson().toJson(person);
How can I do this with the new standard API?

Java API for JSON Processing (JSR-353) does not cover object binding. This will be covered in a separate JSR.

See JSR-367, Java API for JSON Binding (JSON-B), a headline feature in Java™ EE 8.
Document: Json Binding 1.0 Users Guide
// Create Jsonb and serialize
Jsonb jsonb = JsonbBuilder.create();
String result = jsonb.toJson(dog);
// Deserialize back
dog = jsonb.fromJson("{name:\"Falco\", age:4, bitable:false}", Dog.class);

Maybe it's because this question is almost 5 years old (I didn't check which java release has these classes) but there is a standard way with javax.json.* classes:
JsonObject json = Json.createObjectBuilder()
.add("key", "value")
.build();
try(JsonWriter writer = Json.createWriter(outputStream)) {
writer.write(json);
}