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Convert dynamic json to java object with dynamic string value. No key value json structure

I want to convert below JSON structure to java object, Annotation bases.
What will be the pojo java class structure?
{
"Data1":{
"Name":"abc",
"Number":2
}
}
Data1 can by any string-like if it coming as data1 first time, next time it can be like "xyz".
How can we convert it using fasterxml json annotations?

class Node {
public String name;
public int number
}
class ConvertedPojo {
public Map<String, Node> attributes;
}
Since Data1 can be any string you need a map which will store all different string as key and value as json object

Class structure will be :
public class Data1{
#JsonProperty("Name")
private String name;
#JsonProperty("Number")
private int number;
public String getName() {
return name;
}
public void setName(String name) {
name = name;
}
public int getNumber() {
return number;
}
public void setNumber(int number) {
number = number;
}
}
public class Data {
#JsonProperty("Data1")
Object data1;
public Object getData1() {
return data1;
}
public void setData1(Object data1) {
this.data1 = data1;
}
}
Take care of the variable naming convention.
Code to test:
public static void main(String[] args) throws JsonProcessingException {
ObjectMapper mapper = new ObjectMapper();
Data data1 = mapper.readValue("{\"Data1\":{\"Name\":\"abc\",\"Number\":2}}", Data.class);
System.out.println(mapper.writeValueAsString(data1));//{"Data1":{"Name":"abc","Number":2}}
Data data2 = mapper.readValue("{\"Data1\":\"data value\"}", Data.class);
System.out.println(mapper.writeValueAsString(data2));//{"Data1":"data value"}
}

Same named fields with different types in gson parsing

I have a RequestModel defined as
public class RequestModel
{
public class Footage
{
public String date;
public String retrievedAt;
public String videoFileName;
public String availableUntil;
public boolean isAvailable;
}
public class People
{
public String first;
public String last;
}
public static final int USER_BLOCKED = 0;
public static final int USER_ACTIVE = 1;
public static final int USER_WAIT_PIN = 2;
public String _id;
public String status;
public String submittedAt;
public Footage footage;
public People teacher;
public People student;
public ArrayList<MessageModel> messages = new ArrayList<MessageModel>();
public boolean isExpanded = false;
public RequestModel()
{
}
My MessageModel is defined as
public class MessageModel
{
public String _id;
public String statusMessage;
public String submittedAt;
public RequestModel request;
public String status;
public String timestamp;
public boolean isExpanded = false;
public MessageModel()
{
}
}
I have an api call that pulls a single "RequestModel" item. However the messages list in that api call has "request" as a String instead of "RequestModel" object.
Is there any way i can make it parse as a different name or omit it entirely to bypass exceptions causing because of different types.

Use the annotation #SerializedName("") before declaring member to give it a substitute name
ex,
if you json looks like this
{
name:"",
age:0,
items:[...]
}
but your model class have the fields,
class User{
String name;
int age;
Data userItems[];
}
The field userItems in model is named items in the json,
you need to use that annotation on the field:
class User{
String name;
int age;
#SerializedName("items")
Data userItems[];
}
this way GSON will map items to userItems.

Deserializing JSON-valued string

We are using Spring Boot to expose a REST endpoint which is called by a dumb client which delivers us the following:
{
"timestamp": "2016-08-16T14:30.000Z",
"data": "{\"amount\":1,\"product\":\"BASIC PRODUCT\"}"
}
We've created the following objects:
#JsonDeserialize(builder = Message.Builder.class)
public final class Message {
private final String timestamp;
private final Data data;
public String getTimestamp() {...}
public Data getData() {...}
#JsonPOJOBuilder
public static final class Builder {
private String timestamp;
private Data data;
public Builder withTimestamp(final String timestamp) {...}
public Builder withData(final Data data) {...}
}
}
and
#JsonDeserialize(builder = Data.Builder.class)
public final class Data {
private final String product;
private final int amount;
public String getProduct() {...}
public int getAmount() {...}
#JsonPOJOBuilder
public static final class Builder {
private String product;
private int amount;
public Builder withProduct(final String product) {...}
public Builder withAmount(final int amount) {...}
}
}
and exposed the endpoint as
#RequestMapping(consumes = "application/json", method = POST)
public ResponseEntity<?> receive(#RequestBody Message message) {
/// ...
}
but control doesn't even reach the receive method and fails with 400 BAD REQUEST. I believe this has to do with the fact that data is a JSON-valued string. Does Jackson provide any annotation that I can use to force the JSON-valued string to be deserialized as an instance of Data?

The key is in public Builder withData() method of Message.Builder.class to explicitly parse JSON-valued string to Data type. Change the method parameter to String instead of Data and call ObjectMapper().readValue(JSON-valued string, Data.class) to deserialize it into Data.
For example like this:
public Builder withData(final String jsonValue) throws JsonParseException, JsonMappingException, IOException {
Data data = new ObjectMapper().readValue(jsonValue, Data.class);
this.data = data;
return this;
}
For the clarity sake here you are my whole POJOs:
Message:
public final class Message {
private final String timestamp;
private final Data data;
private Message(Builder builder){
this.timestamp = builder.timestamp;
this.data = builder.data;
}
public String getTimestamp() {...}
public Data getData() {...}
#JsonPOJOBuilder
public static final class Builder {
private String timestamp;
private Data data;
private static ObjectMapper mapper = new ObjectMapper();
public Builder withTimestamp(final String timestamp) {
this.timestamp = timestamp;
return this;
}
public Builder withData(final String jsonValue) throws JsonParseException, JsonMappingException, IOException {
Data data = mapper.readValue(jsonValue, Data.class);
this.data = data;
return this;
}
public Message build() {
return new Message(this);
}
} // Builder
}
Data:
public final class Data {
private final String product;
private final int amount;
private Data(Builder builder){
this.product = builder.product;
this.amount = builder.amount;
}
public String getProduct() {...}
public int getAmount() {...}
#JsonPOJOBuilder
public static final class Builder {
private String product;
private int amount;
public Builder withProduct(final String product) {
this.product = product;
return this;
}
public Builder withAmount(final int amount) {
this.amount = amount;
return this;
}
public Data build() {
return new Data(this);
}
} // Builder
}
Hope it helps.

parse json when value of one json becomes key of another json in java

I have two jsons like these
{
"clientId":"patientId",
"vendorId":"businessKey"
}
{
"patientId":"1234",
"businessKey":"abcd"
}
I have java POJOs created like these
public class Patient{
private String patientId;
private String businessKey;
public String getPatientId() {
return patientId;
}
public void setPatientId(String patientId) {
this.patientId = patientId;
}
public String getBusinessKey() {
return businessKey;
}
public void setBusinessKey(String businessKey) {
this.businessKey = businessKey;
}
}
public class Client {
private String clientId;
private String vendorId;
public String getClientId() {
return clientId;
}
public void setClientId(String clientId) {
this.clientId = clientId;
}
public String getVendorId() {
return vendorId;
}
public void setVendorId(String vendorId) {
this.vendorId = vendorId;
}
}
I am using Jackson's ObjectMapper to parse the JSON. What I want to achieve is first read the first JSON, get the value from that and then read the actual value from the second JSON.
Ex: I read the first JSON to getClientId - "patientId"
Then in the second JSON I should read getPatientId - 1234.
How do I achieve this programmatically. I dont want to clutter my code by adding lot many if else blocks. Is there any library that I could use?

LibGDX parsing standard json to an object

I have a very basic problem.
I read though the LibGDX documentation a few times regarding JSON and Google around for an answer but it still does't work..
Basically I'm pulling json from a server like such which works as:
{"id":1,"facebook_id":"23432232","json":"{\"json\":\"test\"}"}
I have a class like this:
public class ServerJson
{
public static final String NAME = "ServerJson";
private int id;
private String facebookID;
private String json;
public ServerJson(){}
public ServerJson(int id, String facebookID, String json)
{
this.id = id;
this.facebookID = facebookID;
this.json = json;
}
public int getId() {
return id;
}
public String getFacebookID() {
return facebookID;
}
public String getJson() {
return json;
}
When I try to parse the code, it doesn't work. I get null:
String resultString = httpResponse.getResultAsString(); //{"id":1,"facebook_id":"23432232","json":"{\"json\":\"test\"}"}
Json json = new Json();
ServerJson serverJson = json.fromJson(ServerJson.class, resultString);
log(serverJson.getFacebookID()); //<< Is null.

Make sure the fields of your object class match up with the fields of the json object.