I have an end-point which returns me this response:
{
"head": {
"status": 200,
"ok": true,
"messages": [],
"errors": [],
"references": {}
},
"body": {
"id": "d57a9c7aef9842c2e31a0f49c",
"flowId": "f57979d06f9842c3e94f1f197",
"creationDate": 1470744494732,
"path": "/luafanti/test",
"version": 0,
"elems": {
"xxx": {
"type": "integer",
"value": 200
}
}
}
}
My question is, how to make a model that can be populated with only a part of my json response. For example, with this:
"xxx": {
"type": "integer",
"value": 200
}
or this:
"elems": {
"xxx": {
"type": "integer",
"value": 200
}
}
Using Jackson, you can define your model as the following:
#JsonIgnoreProperties(ignoreUnknown=true)
public class MyResponseModel {
private Body body;
public void setBody(Body body) {this.body = body;}
public Body getBody() {return body;}
#JsonIgnoreProperties(ignoreUnknown=true)
public static class Body {
private Elems elems;
// getter and setter for elems
}
#JsonIgnoreProperties(ignoreUnknown=true)
public static class Elems {
private Xxx xxx;
// getter and setter for xxx
}
#JsonIgnoreProperties(ignoreUnknown=true)
public static class Xxx {
private String type;
private String value;
// getter and setter for type and value
}
}
The above is quite verbose, particularly if you are only interested in a very small part of the response. It may be more practical to handle the response as a String and then use e.g. JsonPath to extract only the data you are interested in.
You can use simple-json.jar to extract that object from inside the JSONObject
Downloadable Jar Link - simple-json.jar Download Link
Maven Jar Import Maven Repository pom syntax
You actual object is
{
"head": {
"status": 200,
"ok": true,
"messages": [],
"errors": [],
"references": {}
},
"body": {
"id": "d57a9c7aef9842c2e31a0f49c",
"flowId": "f57979d06f9842c3e94f1f197",
"creationDate": 1470744494732,
"path": "/luafanti/test",
"version": 0,
"elems": {
"xxx": {
"type": "integer",
"value": 200
}
}
}
} // hold this complete object in any string reference Variable.
Here I Suppose String jsonString holds the complete json object as above described.
import org.json.simple.parser.JSONParser;
import org.json.simple.parser.JSONObject;
// implemetation logic for extracting jsonObject.
private JSONObject extractFirstBlock(String jsonString) throws ......{
JSONObject jsonObj ;
JSONParser parser=new JSONParser(); // parser to parse string to JSONObject
jsonObj = (JSONObject) parser.parse(jsonString); // parse the Object using parse Method.
String desiredObject = (String) jsonObj.get("body"); // this Object contains your desired output which you wish to receive.
jsonObj = parser.parse(desiredObject);
desiredObject = jsonObj.get("elems"); // you will get your desired object as you expected.
}
Here in desiredObject you will get your expected Values as JSONObject.
"xxx": {
"type": "integer",
"value": 200
}
Related
I have this method which should return different objects from JSON, depending on the type of class in the argument.I tryed it to return a list of objects based on the argument, but I get only LinkedHashMap into ArrayList.
I searched a lot, but everywhere in the solutions the class type is hard-coded.
Is there a way to solve this problem without hard code?
public static <T> List<T> getObjects(Class<T> c) {
CloseableHttpClient rest = HttpClientSessionSingleton.getInstance().getHttpClient();
String urlRequest = (host + "/" +
c.getSimpleName().toLowerCase() + "s");
HttpGet httpGet = new HttpGet(urlRequest);
try (CloseableHttpResponse response = rest.execute(httpGet)) {
HttpEntity entity = response.getEntity();
String jsonString = EntityUtils.toString(entity);
List<T> listObjectFromJson = new ObjectMapper().readValue(jsonString, new TypeReference<List<T>>(){});
return listObjectFromJson;
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
I want to just pass the class type and get objects through one method.
[
{
"id": "73cbc0b5-3dd5-49c4-97cb-6225a19122b5",
"name": "Management",
"fields": [
{
"id": "c2d740d5-4d47-42ae-b616-977b40327812",
"name": "newField1"
}
]
},
{
"id": "dd74384b-717d-4368-b0e4-3f441d5b1ffc",
"name": "IT",
"fields": []
},
{
"id": "03304335-d7d7-46ca-8075-8d5e9feb43c6",
"name": "hhh",
"fields": []
},
{
"id": "e11b4c3f-080e-490d-8ef4-ea301d551a5d",
"name": "NEWWWWW",
"fields": []
},
{
"id": "fec7eeb0-0845-49be-be14-6cdb5fcd3575",
"name": "NEWWWWW",
"fields": []
},
{
"id": "50dfea14-f30a-448c-99df-10bf01d088fa",
"name": "NEWWWWW",
"fields": []
},
{
"id": "a4a1224e-7c66-484c-ae87-dc2ecc058c36",
"name": "NEWWWWW",
"fields": []
}
]
I get this exception when my object has a relationship
Unrecognized field "fields" (class model.orm.Department), not marked as ignorable (2 known properties: "id", "name"])
at [Source: (String)"[{"id":"73cbc0b5-3dd5-49c4-97cb-6225a19122b5","name":"Management","fields":[{"id":"c2d740d5-4d47-42ae-b616-977b40327812","name":"newField1"}]},{"id":"dd74384b-717d-4368-b0e4-3f441d5b1ffc","name":"IT","fields":[]},{"id":"03304335-d7d7-46ca-8075-8d5e9feb43c6","name":"hhh","fields":[]},{"id":"e11b4c3f-080e-490d-8ef4-ea301d551a5d","name":"NEWWWWW","fields":[]},{"id":"fec7eeb0-0845-49be-be14-6cdb5fcd3575","name":"NEWWWWW","fields":[]},{"id":"50dfea14-f30a-448c-99df-10bf01d088fa","name":"NEWWWWW","fie"[truncated 84 chars]; line: 1, column: 77] (through reference chain: java.util.ArrayList[0]->model.orm.Department["fields"])
at com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException.from
You can construct a new JavaType parametric type passing as an argument the List.class to the ObjectMapper.html#getTypeFactory method like below:
public static <T> List<T> getObjects(Class<T> c) throws IOException {
//omitted the lines before creating the mapper including the jsonstring
ObjectMapper mapper = new ObjectMapper();
JavaType type = mapper.getTypeFactory().constructParametricType(List.class, c);
return mapper.readValue(jsonString, type);
}
I have an object nested inside another object in Json file. I want to map this object with fields to a Model class.
{
"code": 200,
"time": "2019-09-05T07:09:44.228+0000",
"data": {
"statuses": [
{
"statusType": "IN_PROGRESS",
"statusTimestamp":"019-09-05T17:04:54+1000"
},
{
"statusType": "SENT",
"statusTimestamp":"2019-09-05T21:04:55+1000"
},
{
"statusType": "OPENED",
"statusTimestamp":"2019-09-05T23:04:55+1000"
},
{
"statusType": "INTERACTION_ID_RECEIVED",
"statusTimestamp":"2019-09-06T00:04:55+1000"
}
]
},
"status": 200,
"message": null,
"errors": null,
}
I want to map the statusType and TimeStamp to a custom model class.
Model Class:
public class Model{
private String statusType;
private DateTime statusTimestamp;
public Model(String statusType, String statusTimestamp) {
this.statusType=statusType;
this.statusTimestamp=new DateTime(statusTimestamp);
}
public String getStatusType() {
return statusType;
}
public void setStatusType(String statusType) {
this.statusType = statusType;
}
public DateTime getStatusTimestamp() {
return statusTimestamp;
}
public void setStatusTimestamp(String statusTimestamp) {
this.statusTimestamp = new DateTime(statusTimestamp);
}
}
I want to map the statuses to this model class and store these objects in a link something like this
List statuses = ParsedJson.read("$..['statuses'][*]", List.class)
If you don't want to model the entire response, you could use Jackson to parse the JSON into tree nodes and then map only the parts you care about:
ObjectMapper mapper = new ObjectMapper();
JsonNode rootNode = mapper.readTree(json);
JsonNode statusesNode = rootNode.path("data").path("statuses");
List<Status> statuses = mapper.convertValue(statusesNode,
new TypeReference<List<Status>>(){});
I saw 2 errors in the json string fixing it should help you to create Object using java or any other language easily.
line 12: " was missing
line 26: invalid placement of ,
Json after fixing issues
{
"code": 200,
"time": "2019-09-05T07:09:44.228+0000",
"data": {
"statuses": [
{
"statusType": "IN_PROGRESS",
"statusTimestamp":"019-09-05T17:04:54+1000"
},
{
"statusType": "SENT",
"statusTimestamp":"2019-09-05T21:04:55+1000"
},
{
"statusType": "OPENED",
"statusTimestamp":"2019-09-05T23:04:55+1000"
},
{
"statusType": "INTERACTION_ID_RECEIVED",
"statusTimestamp":"2019-09-06T00:04:55+1000"
}
]
},
"status": 200,
"message": null,
"errors": null
}
I am working with a server that returns json. One of the elements is either an object or false - it it is non exiting. I know this is very poor implementation of server response and there are quite a few such cases, but this is what I have to work with. How can I deal with this situation? If there is an object I successfully deserialze it, if none - i get error - EXPECTED OBJECT FOUND BOOLEAN.
Even worse, I do not know where I am gonna meet such situations in future on this project.
This is the sample json:
{
"course": {
"id": "47902",
"course": "3844",
"group": "1825",
"teacher": "59502",
"table": "1447",
"client": "1",
"course_id": "3844",
"description": ""
},
"teacher": {
"id": "59502",
"post": "0",
"experience": "",
"dep_experience": "",
"rank": "0",
"online": "1458891283",
"departments": [
null
]
},
"depart": {
"id": "100",
"postcode": "",
"public": "1",
"alias": "",
"faculty": "97",
"client": "1"
},
"progress": false,
"files": [
{
"teacher": {
"id": "59502",
"code": "53bd7c21ad05b03e",
"photo": "1"
},
"files": [
{
"id": "0ffe41e5003ee5c0",
"owner": "59502",
"address": "0ffe41e5003ee5c0",
"type": "f",
"size": "0",
"time": "2015-07-10 14:39:15",
"data": ""
}
]
}
]
}
As you can see progress is false here. Other times it is ordinary object like depart. Deserialization is done by Retrofit 2.
Thanks a lot.
I'm assuming you have a top-level mapping similar to the following one and have configured your Retrofit instance for Gson:
final class Response {
#SerializedName("progress")
#JsonAdapter(FalseAsNullTypeAdapterFactory.class)
final Progress progress = null;
}
final class Progress {
final String foo = null;
}
Note that the progress property is annotated with the #JsonAdapter annotation: we're assuming this is only place were the progress property can be a boolean (if you have many places like this one, you can either annotate each field with this annotation, or .registerTypeAdapter() via GsonBuilder; in case of .registerTypeAdapterFactory() the factory must check against known types in order not to "intercept" all types).
Now, here is a type adapter factory to deal with your issue:
final class FalseAsNullTypeAdapterFactory
implements TypeAdapterFactory {
// Let Gson instantiate it itself
private FalseAsNullTypeAdapterFactory() {
}
#Override
public <T> TypeAdapter<T> create(final Gson gson, final TypeToken<T> typeToken) {
// Get a downstream parser (for simplicity: get the default parser for the given type)
final TypeAdapter<T> delegateTypeAdapter = gson.getDelegateAdapter(this, typeToken);
return new TypeAdapter<T>() {
#Override
public void write(final JsonWriter out, final T value) {
throw new UnsupportedOperationException();
}
#Override
public T read(final JsonReader in)
throws IOException {
// Peek whether the next JSON token is a boolean
if ( in.peek() == BOOLEAN ) {
// And take the this JSON token as a boolean value
// Is it true?
if ( in.nextBoolean() ) {
// Then it's not something we can handle -- probably a boolean field annotated with #JsonAdapter(FalseAsNullTypeAdapterFactory.class)?
throw new MalformedJsonException("Unexpected boolean marker: true");
}
// We're assuming it's null
return null;
}
// If it's not a boolean value, then we just delegate parsing to the original type adapter
return delegateTypeAdapter.read(in);
}
};
}
}
Now just test it:
try ( final Reader reader = getPackageResourceReader(Q43231983.class, "success.json") ) {
final Response response = gson.fromJson(reader, Response.class);
System.out.println(response.progress.foo);
}
try ( final Reader reader = getPackageResourceReader(Q43231983.class, "failure.json") ) {
final Response response = gson.fromJson(reader, Response.class);
System.out.println(response.progress);
}
where the given resources are:
success.json is {"progress":{"foo": "bar"}};
failure.json is {"progress":false}.
The output is as follows:
bar
null
I have a json such as below
{
"apiVersion": "v1",
"metadata": {
"status": {
"statusCode": 0
},
},
"stuff": [
{
"name": {
"text": "red"
},
"properties": [
{
"attributes": {
"shade": "dark"
},
"component": {
"id": "BA1",
}
"type": "Color"
}
]
},
{
"name": {
"text": "Toyota Camry"
},
"properties": [
{
"attributes": {},
"component": {
"id": "MS",
},
"type": "Vehicle"
}
]
},
]
}
I'm using GSON to parse the results like this:
Gson gson = new Gson();
JsonObject json = (JsonObject) gson.fromJson(in, JsonObject.class);
System.out.println(json.get("apiVersion").getAsString());
I can get the apiVersion but don't know how to get elements that are inside the json tree. For example, type...what if I want to output all the different type..in this case Color and Vehicle
I must be missing something here, but why can't you nest calls to getJsonObject? For example, to get the status code:
System.out.println(json.getAsJsonObject("metadata")
.getAsJsonObject("status")
.get("statusCode").getAsInt());
You can create an object in that matter and to parse the json to it (with GSON):
ParsedObject parsedObject = new Gson().fromJson(json, ParsedObject.class);
public class ParsedObject {
#SerializedName(value = "apiVersion")
private String mApiVersion;
#SerializedName(value = "metadata")
private Metadata mMetadata;
}
I've a CXF RESTful service which returns both XML and Json format. I need to add a custom http header in the RESTful service. Here's a sample code snippet.
#GET
#Path("/test")
#Produces("application/xml")
public Response test(
#QueryParam("p") String var
{
TestRequest req = new TestRequest();
req.setVar(var);
TestResponse res = p.getData(req);
return Response.ok(res).header("Result", res.getResult()).build();
}
The above code shows the XML response which sets the custom http header "Result". I'm able to see the new http header in the response header. So far so good.
Now, here's the Json version which internally calls the testService() method to get the result, then use google Gson API to send the result back. This has been working well, till I decided to return the new header. Here's the code snippet.
#GET
#Path("/test/jsonp")
public String testJSONP(
#QueryParam("p") String var,
#QueryParam("cb") String callBack
{
Response resp = test(var);
XStream xs = new XStream(new JsonHierarchicalStreamDriver());
xs.setMode(XStream.NO_REFERENCES);
xs.alias("TestResponse", TestResponse.class);
StringBuilder sb = new StringBuilder();
sb.append(callBack);
sb.append("(");
GsonBuilder gb = new GsonBuilder();
gb.registerTypeAdapter(XMLGregorianCalendar.class, new XMLGregorianCalenderSerializer());
gb.setPrettyPrinting();
Gson gson = gb.create();
sb.append(gson.toJson(resp));
sb.append(")");
return sb.toString();
}
I'm not able to see the http header in Json response.
Any feedback will be highly appreciated.
-Thanks
UPDATE
I added the following code in Json method for my testing.
#GET
#Path("/test/jsonp")
public String testJSONP(
#QueryParam("p") String var,
#QueryParam("cb") String callBack
{
Response resp = test(var);
XStream xs = new XStream(new JsonHierarchicalStreamDriver());
xs.setMode(XStream.NO_REFERENCES);
xs.alias("TestResponse", TestResponse.class);
StringBuilder sb = new StringBuilder();
sb.append(callBack);
sb.append("(");
GsonBuilder gb = new GsonBuilder();
gb.registerTypeAdapter(XMLGregorianCalendar.class, new XMLGregorianCalenderSerializer());
gb.setPrettyPrinting();
Gson gson = gb.create();
sb.append(gson.toJson(resp));
sb.append(")");
return Response.ok(sb.toString(), MediaType.APPLICATION_JSON).header("Result", "50").build();
}
This sets the header value correctly,but the issue is the Json response format seems to have changed. Since this is an existing service, I'm not allowed to do that.
Here's the existing response format
null({
"status": "Completed",
"totalResult": "252",
"bin": [
{
"type": "source",
"value": "documentation",
"ndocs": "243"
},
{
"type": "source",
"value": "wikihelp",
"ndocs": "6"
},
"entries": {
"item": [
{
"url": "http://test.com/test.htm",
"title": "\u003cspan class\u003d\"vivbold qt0\"\u003eXREF\u003c/span\u003e",
"snippet": " Test data.",
"source": "documentation",
"type": "html",
"shortDescription": "Starts the TEST command.",
"category": [
"User"
],
"publishDate": "2012-02-05T12:00:00-0500",
"lastUpdateDate": "2012-03-14T12:00:00-0400",
"topicId": "GUID-7DD70C3C-B8AD-40F1-8A69-5D1EECEAB013"
}
]
}
})
Here's the response after adding this change
null({
"status": 200,
"entity": {
"status": "Completed",
"totalResult": "252",
"bin": [
{
"type": "source",
"value": "documentation",
"ndocs": "243"
},
{
"type": "source",
"value": "wikihelp",
"ndocs": "6"
}
],
"entries": {
"item": [
{
"url": "http://test.com/test.htm",
"title": "\u003cspan class\u003d\"vivbold qt0\"\u003eXREF\u003c/span\u003e",
"snippet": " Test data.",
"source": "documentation",
"type": "html",
"shortDescription": "Starts the TEST command.",
"category": [
"User"
],
"publishDate": "2012-02-05T12:00:00-0800",
"lastUpdateDate": "2012-03-14T12:00:00-0700",
"topicId": "GUID-7DD70C3C-B8AD-40F1-8A69-5D1EECEAB013"
}
]
}
},
"metadata": {
"Result": {
}
}
})
You need to change signature of your method, to return an instance of Response class, instead of a String, and then built the response manually.
From the CXF wiki page:
#Path("/example")
public ExampleResource {
#GET
public Response getSomething() {
return Response.ok(/* some entity */).header("CustomHeader", "CustomValue").build();
}
}
Update
You can also inject HttpServletResponse into your handler using #Context annotation like this:
#Path("/example")
public class Welcome {
#GET
public String getSomething(
#QueryParam("p1") String param1,
#QueryParam("p2") String param2,
#Context HttpServletResponse response) {
response.addHeader("CustomHeader", "CustomValue");
return "my awesome response";
}
}
Note, that there is a CXF-1498 bug in versions prior to 2.1 that causes HttpServletResponse not being injected, so you need a newer CXF version.