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Jackson searches method on wrong level on deserialization

I am trying to read a JSON into the class. Jackson wants to apply a field of a subelement to the element itself, where it of course does not exist.
This is the JSON:
{
"authorizationRequest":{
"scope":["write","read"],
"resourceIds":["metadata"],
"approved":true,
"authorities":[],
"authorizationParameters":{
"scope":"write read",
"response_type":"token",
"redirect_uri":"",
"state":"",
"stateful":"false",
"client_id":"5102686_metadata"
},
"approvalParameters":{},
"state":"",
"clientId":"5102686_metadata",
"redirectUri":"",
"responseTypes":["token"],
"denied":false
},
"credentials":"",
"clientOnly":false,
"name":"testuser"
}
The classes look like the following:
// The main class that I try do deserialize:
public class DeserializedOAuth2Authentication extends OAuth2Authentication{
private String name;
private boolean clientOnly;
private AuthorizationRequest authorizationRequest = new DefaultAuthorizationRequest("", new ArrayList<>());
public DeserializedOAuth2Authentication() {
super(new DefaultAuthorizationRequest("", new ArrayList<>()), null);
}
#Override
#JsonProperty
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
#Override
#JsonProperty
public boolean isClientOnly() {
return clientOnly;
}
public void setClientOnly(boolean clientOnly) {
this.clientOnly = clientOnly;
}
#Override
#JsonProperty
public AuthorizationRequest getAuthorizationRequest() {
return authorizationRequest;
}
public void setAuthorizationRequest(AuthorizationRequest authorizationRequest) {
this.authorizationRequest = authorizationRequest;
}
}
AuthorizationRequest is an interface with all the getters for the listed elements; it is configured to be serialized by a DefaultAuthorizationRequest class also containing the respective setters and implementing fileds with corresponding names.
public class DefaultAuthorizationRequest implements AuthorizationRequest, Serializable {
private Set<String> scope = new LinkedHashSet<String>();
private Set<String> resourceIds = new HashSet<String>();
private boolean approved = false;
private Collection<GrantedAuthority> authorities = new HashSet<GrantedAuthority>();
private Map<String, String> authorizationParameters = new ConcurrentHashMap<String, String>();
private Map<String, String> approvalParameters = new HashMap<String, String>();
private String resolvedRedirectUri;
public Map<String, String> getAuthorizationParameters() {
return Collections.unmodifiableMap(authorizationParameters);
}
public Map<String, String> getApprovalParameters() {
return Collections.unmodifiableMap(approvalParameters);
}
public String getClientId() {
return authorizationParameters.get(CLIENT_ID);
}
public Set<String> getScope() {
return Collections.unmodifiableSet(this.scope);
}
public Set<String> getResourceIds() {
return Collections.unmodifiableSet(resourceIds);
}
public Collection<GrantedAuthority> getAuthorities() {
return Collections.unmodifiableSet((Set<? extends GrantedAuthority>) authorities);
}
public boolean isApproved() {
return approved;
}
public boolean isDenied() {
return !approved;
}
public String getState() {
return authorizationParameters.get(STATE);
}
public String getRedirectUri() {
return resolvedRedirectUri == null ? authorizationParameters.get(REDIRECT_URI) : resolvedRedirectUri;
}
public Set<String> getResponseTypes() {
return OAuth2Utils.parseParameterList(authorizationParameters.get(RESPONSE_TYPE));
}
public void setRedirectUri(String redirectUri) {
this.resolvedRedirectUri = redirectUri;
}
public void setScope(Set<String> scope) {
this.scope = scope == null ? new LinkedHashSet<String>() : new LinkedHashSet<String>(scope);
authorizationParameters.put(SCOPE, OAuth2Utils.formatParameterList(scope));
}
public void setResourceIds(Set<String> resourceIds) {
this.resourceIds = resourceIds == null ? new HashSet<String>() : new HashSet<String>(resourceIds);
}
public void setApproved(boolean approved) {
this.approved = approved;
}
public void setAuthorities(Collection<? extends GrantedAuthority> authorities) {
this.authorities = authorities == null ? new HashSet<GrantedAuthority>() : new HashSet<GrantedAuthority>(
authorities);
}
public void setAuthorizationParameters(Map<String, String> authorizationParameters) {
String clientId = getClientId();
Set<String> scope = getScope();
this.authorizationParameters = authorizationParameters == null ? new HashMap<String, String>()
: new HashMap<String, String>(authorizationParameters);
}
public void setApprovalParameters(Map<String, String> approvalParameters) {
this.approvalParameters = approvalParameters == null ? new HashMap<String, String>()
: new HashMap<String, String>(approvalParameters);
}
....
}
On calling read on the above JSON string I get an exception
com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException: Unrecognized field "scope" (class de.mvbonline.vlx.auth.oauth2.DeserializedOAuth2Authentication), not marked as ignorable (3 known properties: "name", "authorizationRequest", "clientOnly"])
at [Source: (String)"{ "credentials":"", "clientOnly":false, "authorizationRequest":{ "scope":["write","read"], "resourceIds":["metadata"], "approved":true, "authorities":[], "authorizationParameters":{ "scope":"write read", "response_type":"token", "redirect_uri":"", "state":"", "stateful":"false", "[truncated 316 chars]; line: 1, column: 111] (through reference chain: de.mvbonline.vlx.auth.oauth2.DeserializedOAuth2Authentication["scope"])
Of course the field "scope" is not in the context of DeserializedOAuth2Authentication, but in the context of DefaultAuthorizationRequest. Why is Jackson searching in the wrong class for it?
I am unsing Jackson version 2.12.4

Make sure that DefaultAuthorizationRequest can be serialized and deserialized by Jackson. I guess that they are not for several reasons. Two that I can think of:
You have to let Jackson know how to deserialize DefaultAuthorizationRequest class. One possible solution would be to add a #JsonCreator and #JsonProperty to the class. The same applies to GrantedAuthority class.
DefaultAuthorizationRequest has fields of type Map, which need special attention. See these links on how to convert a JSON String to a Map<String, String> or, if the Map has custom objects, how to deserialize into a HashMap of custom objects
Also, you can take a look at Map Serialization and Deserialization with Jackson

I found my problem.
I formerly mapped my concrete implementation of the interface AuthorizationRequest via a handler:
mapper.addHandler(new DeserializationProblemHandler() {
#Override
public Object handleMissingInstantiator(DeserializationContext ctxt, Class<?> instClass, ValueInstantiator valueInsta, JsonParser p, String msg) throws IOException {
if(instClass.isAssignableFrom(AuthorizationRequest.class)) {
return new DeserializedAuthorizationRequest();
}
return super.handleMissingInstantiator(ctxt, instClass, valueInsta, p, msg);
}
});
This seems to be definitely not the same as annotating the field with the concrete class. This now works without problems:
public class DeserializedOAuth2Authentication extends OAuth2Authentication{
...
#Override
#JsonProperty("authorizationRequest")
#JsonDeserialize(as = DeserializedAuthorizationRequest.class)
public AuthorizationRequest getAuthorizationRequest() {
return authorizationRequest;
}
public void setAuthorizationRequest(AuthorizationRequest authorizationRequest) {
this.authorizationRequest = authorizationRequest;
}
}

Flink Collector issue when Collection Object with Map of Object class

I am facing a issue where when i collecting object from flink flatmap collector than i am not getting value collected correctly. I am getting object reference and its not giving me actual value.
dataStream.filter(new FilterFunction<GenericRecord>() {
#Override
public boolean filter(GenericRecord record) throws Exception {
if (record.get("user_id") != null) {
return true;
}
return false;
}
}).flatMap(new ProfileEventAggregateFlatMapFunction(aggConfig))
.map(new MapFunction<ProfileEventAggregateEmittedTuple, String>() {
#Override
public String map(
ProfileEventAggregateEmittedTuple profileEventAggregateEmittedTupleNew)
throws Exception {
String res=null;
try {
ObjectMapper mapper = new ObjectMapper();
mapper.setVisibility(PropertyAccessor.FIELD, Visibility.ANY);
res= mapper.writeValueAsString(profileEventAggregateEmittedTupleNew);
} catch (Exception e) {
e.printStackTrace();
}
return res;
}
}).print();
public class ProfileEventAggregateFlatMapFunction extends
RichFlatMapFunction<GenericRecord, ProfileEventAggregateEmittedTuple> {
private final ProfileEventAggregateTupleEmitter aggregator;
ObjectMapper mapper = ObjectMapperPool.getInstance().get();
public ProfileEventAggregateFlatMapFunction(String config) throws IOException {
this.aggregator = new ProfileEventAggregateTupleEmitter(config);
}
#Override
public void flatMap(GenericRecord event,
Collector<ProfileEventAggregateEmittedTuple> collector) throws Exception {
try {
List<ProfileEventAggregateEmittedTuple> aggregateTuples = aggregator.runAggregates(event);
for (ProfileEventAggregateEmittedTuple tuple : aggregateTuples) {
collector.collect(tuple);
}
}}
Debug Results:
tuple that i am collecting in collector
tuple = {ProfileEventAggregateEmittedTuple#7880}
profileType = "userprofile"
key = "1152473"
businessType = "keyless"
name = "consumer"
aggregates = {ArrayList#7886} size = 1
0 = {ProfileEventAggregate#7888} "geo_id {geo_id=1} {keyless_select_destination_cnt=1, total_estimated_distance=12.5}"
entityType = "geo_id"
dimension = {LinkedHashMap#7891} size = 1
"geo_id" -> {Integer#7897} 1
key = "geo_id"
value = {Integer#7897} 1
metrics = {LinkedHashMap#7892} size = 2
"keyless_select_destination_cnt" -> {Long#7773} 1
key = "keyless_select_destination_cnt"
value = {Long#7773} 1
"total_estimated_distance" -> {Double#7904} 12.5
key = "total_estimated_distance"
value = {Double#7904} 12.5
This i get in my map function .map(new MapFunction<ProfileEventAggregateEmittedTuple, String>()
profileEventAggregateEmittedTuple = {ProfileEventAggregateEmittedTuple#7935}
profileType = "userprofile"
key = "1152473"
businessType = "keyless"
name = "consumer"
aggregates = {GenericData$Array#7948} size = 1
0 = {ProfileEventAggregate#7950} "geo_id {geo_id=java.lang.Object#863dce2} {keyless_select_destination_cnt=java.lang.Object#7cdb4bfc, total_estimated_distance=java.lang.Object#52e81f57}"
entityType = "geo_id"
dimension = {HashMap#7952} size = 1
"geo_id" -> {Object#7957}
key = "geo_id"
value = {Object#7957}
Class has no fields
metrics = {HashMap#7953} size = 2
"keyless_select_destination_cnt" -> {Object#7962}
key = "keyless_select_destination_cnt"
value = {Object#7962}
Class has no fields
"total_estimated_distance" -> {Object#7963}
Please help me to understand what is happening why i am not getting correct data.
public class ProfileEventAggregateEmittedTuple implements Cloneable, Serializable {
private String profileType;
private String key;
private String businessType;
private String name;
private List<ProfileEventAggregate> aggregates = new ArrayList<ProfileEventAggregate>();
private long startTime;
private long endTime;
public String getProfileType() {
return profileType;
}
public void setProfileType(String profileType) {
this.profileType = profileType;
}
public String getKey() {
return key;
}
public void setKey(String key) {
this.key = key;
}
public String getBusinessType() {
return businessType;
}
public void setBusinessType(String businessType) {
this.businessType = businessType;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public List<ProfileEventAggregate> getAggregates() {
return aggregates;
}
public void addAggregate(ProfileEventAggregate aggregate) {
this.aggregates.add(aggregate);
}
public void setAggregates(List<ProfileEventAggregate> aggregates) {
this.aggregates = aggregates;
}
public long getStartTime() {
return startTime;
}
public void setStartTime(long startTime) {
this.startTime = startTime;
}
public long getEndTime() {
return endTime;
}
public void setEndTime(long endTime) {
this.endTime = endTime;
}
#Override
public ProfileEventAggregateEmittedTuple clone() {
ProfileEventAggregateEmittedTuple clone = new ProfileEventAggregateEmittedTuple();
clone.setProfileType(this.profileType);
clone.setKey(this.key);
clone.setBusinessType(this.businessType);
clone.setName(this.name);
for (ProfileEventAggregate aggregate : this.aggregates) {
clone.addAggregate(aggregate.clone());
}
return clone;
}
public class ProfileEventAggregate implements Cloneable, Serializable {
private String entityType;
private Map<String, Object> dimension =new LinkedHashMap<String, Object>();
private Map<String, Object> metrics = new LinkedHashMap<String, Object>();
public Map<String, Object> getDimension() {
return dimension;
}
public void setDimension(Map<String, Object> dimension) {
this.dimension.putAll(dimension);
}
public void addDimension(String dimensionKey, Object dimensionValue) {
this.dimension.put(dimensionKey, dimensionValue);
}
public Map<String, Object> getMetrics() {
return metrics;
}
public void addMetric(String metricKey, Object metricValue) {
this.metrics.put(metricKey, metricValue);
}
public void setMetrics(Map<String, Object> metrics) {
this.metrics.putAll(metrics);
}
public String getEntityType() {
return entityType;
}
public void setEntityType(String entityType) {
this.entityType = entityType;
}
#Override
public ProfileEventAggregate clone() {
ProfileEventAggregate clone = new ProfileEventAggregate();
clone.setEntityType(this.entityType);
clone.getDimension().putAll(this.getDimension());
clone.getMetrics().putAll(this.metrics);
return clone;
}

When you don't enableObjectReuse, objects are copied with your configured serializer (seems to be Avro?).
In your case, you use Map<String, Object> where you cannot infer a plausible schema.
The easiest fix would be to enableObjectReuse. Else make sure your serializer matches your data. So you could add a unit test where you use AvroSerializer#copy and make sure your POJO is properly annotated if you want to stick with Avro reflect or even better go with a schema first approach, where you generate your Java POJO with a Avro schema and use specific Avro.
Let's discuss some alternatives:
Use GenericRecord. Instead of converting it to a Java type, directly access GenericRecord. This is usually the only way when the full record is flexible (e.g. your job takes any input and writes it out to S3).
Denormalize schema. Instead of having some class Event { int id; Map<String, Object> data; } you would use class EventInformation { int id; String predicate; Object value; }. You would need to group all information for processing. However, you will run into the same type issues with Avro.
Use wide-schema. Looking at the previous approach, if the different predicates are known beforehand, then you can use that to craft a wide-schema class Event { int id; Long predicate1; Integer predicate2; ... String predicateN; } where all oft he entries are nullable and most of them are indeed null. To encode null is very cheap.
Ditch Avro. Avro is fully typed. You may want to use something more dynamic. Protobuf has Any to support arbitrary submessages.
Use Kryo. Kryo can serialize arbitrary object trees at the cost of being slower and having more overhead.
If you want to write the data, you also need to think about a solution where the type information is added for proper deserialization. For an example, check out this JSON question. But there are more ways to implement it.

Parsing retrofit response into custom object containing custom object on Android

I have a problem with parsing my custom response because the I have a response with Localization properties.
I am recieving a response that looks something like this:
[
{
"id": "dummyID1",
"name.en_US": "dummyNameEn1",
"name.fi_FI": "dummyNameFi1"
},
{
"id": "dummyID2",
"name.en_US": "dummyNameEn2",
"name.fi_FI": "dummyNameFi2"
},
{
"id": "dummyID3",
"name.en_US": "dummyNameEn3",
"name.fi_FI": "dummyNameFi3"
}...
]
And to parse that I have created a custom class Device.java:
public class Device {
public String id;
public LocalizedString name;
public Device(String id, LocalizedString name) {
this.id = id;
this.name = name;
}
//Getters and setters
}
Now here we have a custom object named LocalizedString.java:
public class LocalizedString implements Parcelable {
public static final Creator<LocalizedString> CREATOR = new Creator<LocalizedString>() {
#Override
public LocalizedString createFromParcel(Parcel in) {
return new LocalizedString(in);
}
#Override
public LocalizedString[] newArray(int size) {
return new LocalizedString[size];
}
};
private String en_US;
private String fi_FI;
public LocalizedString(String en, String fi) {
this.en_US = en;
this.fi_FI = fi;
}
protected LocalizedString(Parcel in) {
en_US = in.readString();
fi_FI = in.readString();
}
#Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeString(en_US);
dest.writeString(fi_FI);
}
//Getters, setters
}
Now in my response I want to create a list of Device's but it does not seem to understand how the ´LocalizedString´ works. Since my request is returning a <List<Device>> I cannot really customly parse it either.
Here is how I try to parse it:
Call<List<Device>> call = getMainActivity().getRestClient().getDevices();
call.enqueue(new Callback<List<Device>>() {
#Override
public void onResponse(Call<List<Device>> call, Response<List<Device>> response) {
if (isAttached()) {
if (response.isSuccessful()) {
// get data
List<Device> items = response.body();
}
}
}
#Override
public void onFailure(Call<List<Device>> call, Throwable t) {
if (isAttached()) {
Logger.debug(getClass().getName(), "Could not fetch installation document devices past orders", t);
getMainActivity().showError(R.string.error_network);
}
}
});
And:
#GET("document/devices")
Call<List<Device>> gettDevices();
What am I supposed to do in this situation to bind the name to the Device and later be able to either get en_US or fi_FI.

Better you can write it like this
public class Device {
#SerializedName("id")
public String id;
#SerializedName("name.en_US")
public String en;
#SerializedName("name.fi_FI")
public String fi;
public Device(String id, String english, String fi) {
this.id = id;
this.en = english;
this.fi = fi;
}
//Getters and setters
}

If you can control the source of the JSON, then a modification of that JSON structure is easy to solve your problem.
If you can not, the one way we can use to solve your problem is to use Jackson and custom deserializer:
public class DeviceDeserializer extends StdDeserializer<Device> {
public DeviceDeserializer() {
this(null);
}
public DeviceDeserializer(Class<?> vc) {
super(vc);
}
#Override
public Device deserialize(JsonParser jp, DeserializationContext ctxt)
throws IOException, JsonProcessingException {
JsonNode node = jp.getCodec().readTree(jp);
String id = getStringValue(node, "id");
String en = getStringValue(node, "name.en_EN");
String fi = getStringValue(node, "name.fi_FI");
LocalizedString localized = new LocalizedString(en, fi);
return new Device(id, localizedString);
}
private String getStringValue(JsonNode node, String key) {
// Throws exception or use null is up to you to decide
return Optional.ofNullable(node.get("id"))
.map(JsonNode::asText)
.orElse(null);
}
}
Manually register the deserializer yourself or using the annotation:
#JsonDeserialize(using = DeviceDeserializer.class)
public class Device {
...
Note that you must enable retrofit jackson converter plugin: (see the Retrofit Configuration part)
Retrofit retrofit = new Retrofit.Builder()
.baseUrl("https://api.github.com")
.addConverterFactory(JacksonConverterFactory.create())
.build();

Read this: Get nested JSON object with GSON using retrofit

Build dynamic JSON

I'm trying to build dynamic json request in java to send to my c++ server. I'm using the GSON library.
This is my json example:
{
"nodes": {
"12131231231231241": {
"gToken": {
"token": "AABBCCDDEEFF99001122334455667788"
},
"objects": {
"WATER_CONTROL_1": "0"
}
},
"7682642342432423": {
"userAuthentication": {
"userEmail": "user#mail.com",
"userPassword": "userPassword"
},
"objects": {
"LIGHT_1_CONTROL": "1"
}
}
}
}
If you can see the nodes object is dynamic. Inside him i can have a lot of items (in the example i put two, representing by 12131231231231241 and 7682642342432423). Inside each item the authentication method can be different (by token, by email/password) and inside objects item i can have a lot of different dynamic items too.
The part to send to my c++ server, parse the JSON and do the all validations (authetication for example) is already done and working (i test this json example inside c++ string, encode to json and do the parse, get the all items,etc).
So my problem is to build my class to send the request with some struct to corresponding to this dynamic json.
I already implement some other class to send json to my server and its work because i already know the json expected and on other cases the json have a static/fixed content.
My class for this dynamic json:
public class MonitorControlGetRequestArgs implements SerializableJSON {
Nodes nodes;
public MonitorControlGetRequestArgs() {
nodes = new Nodes();
}
static class Nodes{
public Nodes(){
}
}
public static MonitorControlGetRequestArgs fromStringJson(String data){
try {
Gson gson = new Gson();
return gson.fromJson(data, MonitorControlGetRequestArgs.class);
}
catch(Exception e){
return null;
}
}
public static MonitorControlGetRequestArgs fromBytesJson(byte[] data){
if (data == null)
return null;
try {
String str = new String(data, "utf-8");
return fromStringJson(str);
}
catch (Exception e) {
return null;
}
}
#Override
public String toJsonString(){
try{
Gson gson = new Gson();
return gson.toJson(this);
}
catch(Exception e){
return null;
}
}
#Override
public byte[] toJsonBytes(){
try {
return this.toJsonString().getBytes("utf-8");
}
catch (Exception e){
return null;
}
}
}
I create a static class Nodes empty to show you. In my server c++ i receive the item nodes in json format, but now i have a lot of doubts how to build the struct inside nodes to corresponding to my dynamic json.
I hope you understand my doubts. If you don't understand something tell to me.
EDIT 1 - (try to use the example of Andriy Rymar)
I try to simulate this json:
{
"nodes": {
"1317055040393017962": {
"userAuthentication": {
"userEmail": "rr#rr.com",
"userPassword": "rr123"
}
}
}
}
My request class:
public class MonitorControlGetRequestArgs implements SerializableJSON
{
private final static String nodeTemplate = "\"%s\":%s";
List nodes = new ArrayList<>();
public MonitorControlGetRequestArgs(UserAuthentication userAuthentication)
{
JsonData jsonData = new JsonData();
jsonData.addNode(new Node("1317055040393017962", new NodeObject(userAuthentication)));
}
static class Node
{
private final String nodeName;
private final Object nodeBody;
public Node(String nodeName, Object nodeBody) {
this.nodeName = nodeName;
this.nodeBody = nodeBody;
}
public String getNodeName() {
return nodeName;
}
public Object getNodeBody() {
return nodeBody;
}
}
static class JsonData {
List<Node> nodes = new ArrayList<>();
public void addNode(Node node){
nodes.add(node);
}
}
static class NodeObject
{
UserAuthentication userAuthentication;
public NodeObject(UserAuthentication userAuthentication)
{
this.userAuthentication = userAuthentication;
}
}
public static MonitorControlGetRequestArgs fromStringJson(String data)
{
try
{
Gson gson = new Gson();
return gson.fromJson(data, MonitorControlGetRequestArgs.class);
}
catch(Exception e)
{
return null;
}
}
public static MonitorControlGetRequestArgs fromBytesJson(byte[] data)
{
if (data == null) return null;
try
{
String str = new String(data, "utf-8");
return fromStringJson(str);
}
catch (Exception e)
{
return null;
}
}
#Override
public String toJsonString()
{
try
{
Gson gson = new Gson();
return gson.toJson(this);
}
catch(Exception e)
{
return null;
}
}
#Override
public byte[] toJsonBytes()
{
try
{
return this.toJsonString().getBytes("utf-8");
}
catch (Exception e)
{
return null;
}
}
}
EDIT 2
I will try to explain better,i believe I was not totally explicit. My application java is a REST application that send json to my c++ server. In my server i receive the json, i do the parse, i do the validation, the operations, etc and return back to my java client the response in json too.
For example, imagine that my json request body (to create a new user for example) is something like this:
{
"userInformation": {
"name": "user name",
"age": 33
}
}
For this i don't have any doubts how to do (i already implement a lot of requests very similar). I can create a static class like this:
static class UserInfo
{
String name;
String age;
public UserInfo(String name, String age)
{
this.name = name;
this.age = age;
}
}
And inside a request class (very similar to a class like i copy before - MonitorControlGetRequestArgs) i create a new instance to my UserInfo
UserInfo userInformation = new UserInfo (name, age)
In this case its easy because the request json body is static. I already now that i have a userInformation section and inside i have a name and age. To create a list with userInfo (to create multiple users at same time for example) i already implement things like this.
But now, for this specific case i have this json:
{
"nodes": {
"12131231231231241": {
"gToken": {
"token": "AABBCCDDEEFF99001122334455667788"
},
"objects": {
"WATER_CONTROL_1": "0"
}
},
"7682642342432423": {
"userAuthentication": {
"userEmail": "user#mail.com",
"userPassword": "userPassword"
},
"objects": {
"LIGHT_1_CONTROL": "1"
"LIGHT_3_CONTROL": "0"
}
}
}
}
So in this case i have some problems. In these example i put two items (12131231231231241,7682642342432423) but the user can send more (3,4,5,50,100). In the other hand inside nodes i have two sections (12131231231231241,7682642342432423) but this numbers are some ids that i use in my app and i never know that ids the user will put. In last example ( userInformation ) its simple because i create a userInformation section because i already know that the user always put this section, it is static. In these new json request i dont know, because i never now what value he put, i only know that is a string. The authentication method i dont have problems to create. But other problem that i expected to have is in objects section, because the user can put to a lot of objects and i never know what is the key (in userInformation i know that the keys are always the name and age for example and only exits these two keys, i these new case i dont know what is the keys and what are the number of pair of keys/values he put).
EDIT 3 -
I implement this code and i could almost produce all the structure I need. I'm using the gson same.
Nodes nodes;
public MonitorControlGetRequestArgs(String userEmail, String userPassword, Map <String,String> objects)
{
nodes = new Nodes(userEmail, userPassword, objects);
}
static class Nodes
{
AuthenticationMethod authenticationMethod;
Map <String,String> objects;
public Nodes(String userEmail, String userPassword, Map <String,String> objects)
{
authenticationMethod = new AuthenticationMethod(userEmail, userPassword);
this.objects = objects;
}
}
The result json:
{
"nodes": {
"authenticationMethod": {
"userAuthentication": {
"userEmail": "user#mail.com",
"userPassword": "userPassword"
}
},
"objects": {
"aa": "aaaaaaaaaaaaa",
"bbbbbbb": "bbbbb",
"ccdd": "ccddccdd"
}
}
}
Know i only need to add some struct to support this json:
{
"nodes": {
"7682642342432423": {
"authenticationMethod": {
"userAuthentication": {
"userEmail": "user#mail.com",
"userPassword": "userPassword"
}
},
"objects": {
"0": "Hammersmith & City",
"1": "Circle",
"dasd": "dasda"
}
}
}
}
Note: The objects is a map, so i can put the number of objects string/string that i want. Know i need to do something to support the previous json with the 7682642342432423, 12131231231231241, etc, etc..
EDIT 4 - final
Map <String, Obj> nodes;
public MonitorControlGetRequestArgs(Map <String, Obj> nodes)
{
this.nodes = nodes;
}
static class Obj
{
AuthenticationMethod authenticationMethod;
Map <String,String> objects;
public Obj(String userEmail, String userPassword, Map <String,String> objects)
{
authenticationMethod = new AuthenticationMethod(userEmail, userPassword);
this.objects = objects;
}
}
Json that arrive in my server (like i want)
{
"nodes": {
"12131231231231241": {
"authenticationMethod": {
"userAuthentication": {
"userEmail": "user#mail.com",
"userPassword": "userPassword"
}
},
"objects": {
"aa": "aaaaaaaaaaaaa",
"bbbbbbb": "bbbbb",
"ccdd": "ccddccdd"
}
},
"777777777777777": {
"authenticationMethod": {
"userAuthentication": {
"userEmail": "user#mail.com",
"userPassword": "userPassword"
}
},
"objects": {
"aa": "aaaaaaaaaaaaa",
"bbbbbbb": "bbbbb",
"ccdd": "ccddccdd"
}
}
}
}

Here is improved code from previous example that is more flexible and has better serialization mechanism :
public class ForTestApplication {
public static void main(String[] args) {
NodeArray jsonContainer = new NodeArray(
new Node("nodes", new NodeArray(
new Node("12131231231231241", new NodeArray(
new Node("gToken",
new Node("token", "AABBCCDDEEFF99001122334455667788")),
new Node("objects", new NodeArray(
new Node("WATER_CONTROL_1", "0"),
new Node("WATER_CONTROL_2", "1")
)))),
new Node("7682642342432423", new NodeArray(
new Node("userAuthentication", new NodeArray(
new Node("userEmail","user#mail.com"),
new Node("userPassword","userPassword")
)),
new Node("objects", new NodeArray(
new Node("WATER_CONTROL_1", "0"),
new Node("WATER_CONTROL_2", "1")
))
))
)));
System.out.println(jsonContainer.toJSONString());
}
}
class NodeArray {
private static final String NODE_TEMPLATE = "\"%s\":%s";
private static final Gson gson = new Gson();
private List<Node> nodes = new ArrayList<>();
public NodeArray(Node... nodes){
addNode(nodes);
}
public void addNode(Node... node){
nodes.addAll(Arrays.asList(node));
}
public String toJSONString() {
return nodes.stream()
.map(node -> String.format(NODE_TEMPLATE, node.getNodeName(), getNodeBodyAsJSON(node)))
.collect(Collectors.joining(",", "{", "}"));
}
private String getNodeBodyAsJSON(Node node) {
if (node.getNodeBody() instanceof NodeArray) {
return ((NodeArray) node.getNodeBody()).toJSONString();
}
return gson.toJson(node.getNodeBody());
}
}
class Node {
private final String nodeName;
private final Object nodeBody;
public Node(String nodeName, Object nodeBody) {
this.nodeName = nodeName;
this.nodeBody = nodeBody;
}
public String getNodeName() {
return nodeName;
}
public Object getNodeBody() {
return nodeBody;
}
}
The output of such application is :
{"nodes":{"12131231231231241":{"gToken":{"nodeName":"token","nodeBody":"AABBCCDDEEFF99001122334455667788"},"objects":{"WATER_CONTROL_1":"0","WATER_CONTROL_2":"1"}},"7682642342432423":{"userAuthentication":{"userEmail":"user#mail.com","userPassword":"userPassword"},"objects":{"WATER_CONTROL_1":"0","WATER_CONTROL_2":"1"}}}}
Pretty view is :
NOTICE : this example use constructors to build complex structures but I highly recommend to use builder pattern for such case. Code will be clearer and better.

Here is example of what you need using Gson. But if you would like to use something else, for example OrgJson then the code will be more clear and without String templates.
public class ForTestApplication {
private final static String nodeTemplate = "\"%s\":%s";
public static void main(String[] args) {
JsonData jsonData = new JsonData();
jsonData.addNode(new Node("user-1", new TestObject(62, "James", "Gosling")));
jsonData.addNode(new Node("user-2", new TestObject(53, "James", "Hetfield")));
System.out.println(jsonData.toJSONStirng());
}
static class JsonData {
List<Node> nodes = new ArrayList<>();
public void addNode(Node node){
nodes.add(node);
}
public String toJSONStirng() {
Gson gson = new Gson();
return nodes.stream()
.map(node -> String.format(nodeTemplate, node.getNodeName(), gson.toJson(node.getNodeBody())))
.collect(Collectors.joining(",", "{", "}"));
}
}
static class Node {
private final String nodeName;
private final Object nodeBody;
public Node(String nodeName, Object nodeBody) {
this.nodeName = nodeName;
this.nodeBody = nodeBody;
}
public String getNodeName() {
return nodeName;
}
public Object getNodeBody() {
return nodeBody;
}
}
static class TestObject {
private int age;
private String firstName;
private String lastName;
public TestObject(int age, String firstName, String lastName) {
this.age = age;
this.firstName = firstName;
this.lastName = lastName;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
}
}
Output :
{"user-1":{"age":62,"firstName":"James","lastName":"Gosling"},"user-2":{"age":53,"firstName":"James","lastName":"Hetfield"}}
Pretty view :

Deserialize a JSON containing a list of objects using Gson

I'm trying to deserialize a JSON which containes a String and a list of objects in my Spring web application.
JSON
[
{
"jsonrpc":"2.0",
"result":[
{
"event":{
"id":"27809810",
"name":"Spezia v Trapani",
"countryCode":"IT",
"timezone":"Europe/London",
"openDate":"2016-05-28T16:30:00.000Z"
},
"marketCount":13
},
{
"event":{
"id":"27811083",
"name":"Torino U19 v Atalanta U19",
"countryCode":"IT",
"timezone":"Europe/London",
"openDate":"2016-05-29T16:15:00.000Z"
},
"marketCount":18
},
...
]
My classes are:
ListEventsResponse class
public class ListEventsResponse {
private String jsonrpc;
private List<ListEventsResult> result;
public ListEventsResponse() { }
public String getJsonrpc() {
return jsonrpc;
}
public void setJsonrpc(String jsonrpc) {
this.jsonrpc = jsonrpc;
}
public List<ListEventsResult> getResult() {
return result;
}
public void setResult(List<ListEventsResult> result) {
this.result = result;
}
}
ListEventsResult class
public class ListEventsResult {
private Event event;
private int marketCount;
public ListEventsResult() { }
public Event getEvent() {
return event;
}
public void setEvent(Event event) {
this.event = event;
}
public int getMarketCount() {
return marketCount;
}
public void setMarketCount(int marketCount) {
this.marketCount = marketCount;
}
}
I have also Event class, composed by 5 String (id, name, etc.).
Controller
[...]
ListEventsResponse listEvents = new Gson().fromJson(response.toString(), ListEventsResponse.class);
List<ListEventsResult> eventsList = listEvents.getResult();
return new ModelAndView("page", "eventsList", eventsList);
My .jsp page
[...]
<c:forEach items="${eventsList}" var="listEventsResult">
Match: <c:out value="${listEventsResult.name}"/>
</c:forEach>
[...]
My code runs and doesn't give any error, but no match is shown on my page, in fact listEvents doesn't contains any object.
I can't understand how to deserialize properly the list of objects, so my question is: which logic is behind the deserialization of a json which contains a list of objects?
I post my code just to explain better my problem.

As you have a Json Array as response , you need to deserialize like below
Gson gson = new Gson();
Type type = new TypeToken<List<ListEventsResponse>>(){}.getType();
List<ListEventsResponse> events = (List<ListEventsResponse>) gson.fromJson(response.toString(), type);