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Java - Extract array String from JSON and convert to JSON format

I have a JSON String as below:
"{ \"password\":\"des123\",\"ROU_DATA\":[{\"FORM_RECEIVING_TIME\":\"12:00:00\",\"REMARKS\":\"Redemption of Unit\"}, {\"FORM_RECEIVING_TIME\":\"13:00:00\",\"REMARKS\":\"sALE of Unit\"}] }";
Now I want to extract the Array from it and need to use it as a separate pojo class so that I can iterate over each value..
Now the problem is, when I try to convert the complete String to Map and get the Array value from the map.. It transforms its format to MAp format like:
{FORM_RECEIVING_DATE = 12:00:00, etc..}
However json string should be {"FORM_RECEIVING_DATE": "12:00:00", etc..}
due to the MAp format its now allowing me to parse it using my POJO Class..
Please help to convert it to my JSONFormat ...
**NOTE: Please note that I can only use Jackson **.
CLASS A
ObjectMapper mapper2 = new ObjectMapper();
Map<String, Object> map;
map = mapper2.readValue(json, new TypeReference<Map<String, Object>>(){});
System.out.println("map: " + map.get("ROU_DATA") );
String array = map.get("ROU_DATA").toString();
String json2 = new ObjectMapper().writeValueAsString(array.replace("[", "").replace("]", ""));
String json3 = new ObjectMapper().writeValueAsString(json2);
System.out.println("json2>>" + json2);
System.out.println("json2>>" + json3);
mapper.configure(JsonParser.Feature.ALLOW_UNQUOTED_FIELD_NAMES, true);
// 1. convert JSON array to Array objects
ROU[] pp1 = mapper.readValue("{" + array.replace("=", ":") + "}", ROU[].class);
for (ROU person : pp1) {
System.out.println(person.getRemarks());
}
CLASS B
import com.fasterxml.jackson.annotation.JsonProperty;
public class ROU {
#JsonProperty("FORM_RECEIVING_TIME")
private String formdate;
#JsonProperty("REMARKS")
private String remarks;
public String getFormdate() {
return formdate;
}
public void setFormdate(String formdate) {
this.formdate = formdate;
}
public String getRemarks() {
return remarks;
}
public void setRemarks(String remarks) {
this.remarks = remarks;
}
}

map.get("ROU_DATA") returns a List object, and the toString() method of List does not generate JSON text.
You don't need to convert back to a JSON text just to get the ROU[] created, just call convertValue(...).
String input = "{ \"password\":\"des123\",\"ROU_DATA\":[{\"FORM_RECEIVING_TIME\":\"12:00:00\",\"REMARKS\":\"Redemption of Unit\"}, {\"FORM_RECEIVING_TIME\":\"13:00:00\",\"REMARKS\":\"sALE of Unit\"}] }";
ObjectMapper mapper2 = new ObjectMapper();
Map<?, ?> json = mapper2.readValue(input, Map.class);
ROU[] pp1 = mapper2.convertValue(json.get("ROU_DATA"), ROU[].class);
for (ROU person : pp1)
System.out.println(person.getRemarks());
Output
Redemption of Unit
sALE of Unit

class A
public class ROU {
#JsonProperty("FORM_RECEIVING_TIME")
private String formdate;
#JsonProperty("REMARKS")
private String remarks;
public String getFormdate() {
return formdate;
}
public void setFormdate(String formdate) {
this.formdate = formdate;
}
public String getRemarks() {
return remarks;
}
public void setRemarks(String remarks) {
this.remarks = remarks;
}
}
class B
public class ObjOuter {
private String password;
#JsonProperty("ROU_DATA")
private List<ROU> rous;
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public List<ROU> getRous() {
return rous;
}
public void setRous(List<ROU> rous) {
this.rous = rous;
}
}
json to Object
ObjectMapper mapper = new ObjectMapper();
try {
ObjOuter outer = mapper.readValue(str, ObjOuter.class);
for (ROU rou : outer.getRous()) {
System.out.println(rou.getFormdate());
System.out.println(rou.getRemarks());
}
} catch (IOException e) {
e.printStackTrace();
}

Cannot deserialize instance of `org.json.JSONObject`

I have a basic SpringBoot 2.1.5.RELEASE app. Using Spring Initializer, JPA, embedded Tomcat, Thymeleaf template engine, and package as an executable JAR file with some RestControllers.
In 1 of the controller this is the body I send:
{
"depositHotel": "xxx",
"destinationHotel": "aaa",
"depositHotelAmount": "0.2",
"destinationHotelAmount": "4",
"destinationAddress": [{
"address": "asdf",
"tag": ""
}],
"refundAddress": [{
"address": "pio",
"tag": ""
}]
}
so I create this class to use it as a RequestBody:
public class HotelswitchHotelOrderRequestBody {
public static class Builder {
private String depositHotel;
private String destinationHotel;
private Float depositHotelAmount;
private Float destinationHotelAmount;
private JSONObject destinationAddress;
private JSONObject refundAddress;
public Builder(String depositHotel, String destinationHotel) {
this.depositHotel = depositHotel;
this.destinationHotel = destinationHotel;
}
public Builder withDepositHotelAmount (Float depositHotelAmount) {
this.depositHotelAmount = depositHotelAmount;
return this;
}
public Builder withDestinationHotelAmount (Float destinationHotelAmount) {
this.destinationHotelAmount = destinationHotelAmount;
return this;
}
public Builder toDestinationAddress (JSONObject destinationAddress) {
this.destinationAddress = destinationAddress;
return this;
}
public Builder toRefundAddress (JSONObject refundAddress) {
this.refundAddress = refundAddress;
return this;
}
public HotelswitchHotelOrderRequestBody build(){
HotelswitchHotelOrderRequestBody order = new HotelswitchHotelOrderRequestBody();
order.depositHotel = this.depositHotel;
order.depositHotelAmount = this.depositHotelAmount;
order.destinationAddress = this.destinationAddress;
order.destinationHotel = this.destinationHotel;
order.destinationHotelAmount = this.destinationHotelAmount;
order.refundAddress = this.refundAddress;
return order;
}
}
private String depositHotel;
private String destinationHotel;
private Float depositHotelAmount;
private Float destinationHotelAmount;
private JSONObject destinationAddress;
private JSONObject refundAddress;
private HotelswitchHotelOrderRequestBody () {
//Constructor is now private.
}
public String getDepositHotel() {
return depositHotel;
}
public void setDepositHotel(String depositHotel) {
this.depositHotel = depositHotel;
}
public String getDestinationHotel() {
return destinationHotel;
}
public void setDestinationHotel(String destinationHotel) {
this.destinationHotel = destinationHotel;
}
public Float getDepositHotelAmount() {
return depositHotelAmount;
}
public void setDepositHotelAmount(Float depositHotelAmount) {
this.depositHotelAmount = depositHotelAmount;
}
public Float getDestinationHotelAmount() {
return destinationHotelAmount;
}
public void setDestinationHotelAmount(Float destinationHotelAmount) {
this.destinationHotelAmount = destinationHotelAmount;
}
public JSONObject getDestinationAddress() {
return destinationAddress;
}
public void setDestinationAddress(JSONObject destinationAddress) {
this.destinationAddress = destinationAddress;
}
public JSONObject getRefundAddress() {
return refundAddress;
}
public void setRefundAddress(JSONObject refundAddress) {
this.refundAddress = refundAddress;
}
}
But I have this error when receiving the object:
JSON parse error: out of START_ARRAY token; nested exception is com.fasterxml.jackson.databind.exc.MismatchedInputException: Cannot deserialize instance of `org.json.JSONObject` out of START_ARRAY token

JSONObject's representation in actual JSON is a hash i.e. {...}. In your json data you're providing an array of hashes [{...}] which is not the same. Judging from your domain I don't think it has to be multiple values, so you can just omit [] in your payload and if it does then the fields in your Java class can be defined as JSONArray.
However, I think you should go with defining an Address class and either using
private Address destinationAddress;
private Address refundAddress;
or if it indeed does have to be an object array
private List<Address> destinationAddresses;
private List<Address> refundAddresses;

I had a similar usecase , where I could not define the json to a POJO. Using com.fasterxml.jackson.databind.JsonNode instead of the JSONObject worked.

Java JSON Processing

I'm having a hard time processing the below JSON with Java, which is being returned from on an external Ansible playbook:
{"Sample":
{
"tag_description":"abc","tag_category_id":"def","tag_id":"ghi"
},
"Sample1":
{
"tag_description":"jkl","tag_category_id":"mno","tag_id":"pqr"
}
}
I've been able to successfully parse one section of the JSON using a custom deserializer, though it only ever gets the first section. Any ideas are hugely appreciated.
#JsonComponent
public class TagSerializer extends JsonDeserializer<Tag> {
#Override
public Tag deserialize(JsonParser jsonParser,
DeserializationContext deserializationContext) throws IOException,
JsonProcessingException {
ObjectMapper mapper = new ObjectMapper();
JsonFactory factory = mapper.getFactory();
JsonNode treeNode = jsonParser.getCodec().readTree(jsonParser);
Iterator<Map.Entry<String, JsonNode>> fields = treeNode.fields();
String name = "";
// collect the tag name
Map.Entry<String, JsonNode> entry = fields.next();
name = entry.getKey();
// now that we have the tag name, parse it as a separate JSON object
JsonNode node = entry.getValue();
// get the values from the JSON
String description = node.get("tag_description").asText();
String category_id = node.get("tag_category_id").asText();
String tag_id = node.get("tag_id").asText();
return new Tag(name, category_id, description, tag_id);
}
}
I'm calling the method from a Spring Boot REST API endpoint, and my 'tag' model is a Spring entity:
'Tag' model:
#Entity
#JsonDeserialize(using = TagSerializer.class)
public class Tag {
#Id
#GeneratedValue(strategy=GenerationType.AUTO)
private Long id;
private String name;
private String tag_category_id;
private String tag_description;
private String tag_id;
//JPA requires that a default constructor exists
//for entities
protected Tag() {}
public Tag(String name,
String tag_category_id,
String tag_description,
String tag_id) {
this.name = name;
this.tag_category_id = tag_category_id;
this.tag_description = tag_description;
this.tag_id = tag_id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getTag_category_id() {
return tag_category_id;
}
public void setTag_category_id(String tag_category_id) {
this.tag_category_id = tag_category_id;
}
public String getTag_description() {
return tag_description;
}
public void setTag_description(String tag_description) {
this.tag_description = tag_description;
}
public String getTag_id() {
return tag_id;
}
public void setTag_id(String tag_id) {
this.tag_id = tag_id;
}
public String toString() {
return "<Tag:[Name: " + this.name + "],[tag_category: "+
this.tag_category_id + "],[tag_description: "+
this.tag_description + "],[tag_id:"+this.tag_id+"]";
}
}
Spring Boot endpoint:
#PostMapping(value="/store", consumes = APPLICATION_JSON_VALUE)
public void tagJson(#RequestBody String json) {
// delete any existing tags
tagRepository.deleteAll();
//lets modify the json to make it look nicer
String modjson = "["+json+"]";
ObjectMapper mapper = new ObjectMapper();
try {
Tag[] tags = mapper.readValue(modjson, Tag[].class);
for (Tag t : tags)
tagRepository.save(t);
} catch (Exception exception) {
exception.printStackTrace();
}
}

If you are using Spring MVC consider explicitly declare desired type when referreing to #RequestBody and let the framework do the job for you
#PostMapping(value="/store", consumes = APPLICATION_JSON_VALUE)
public void tagJson(#RequestBody Map<String, Tag> json) {
// Do not mess with ObjectMapper here, Spring will do the thing for you
}

This isn't a direct answer but a guide in a possible direction, using Gson.
package test;
import java.util.Map;
import com.google.gson.Gson;
public class JsonTest {
public static void main(final String... args) {
new JsonTest().run();
}
public void run() {
final Gson gson = new Gson();
final Map<?, ?> result = gson.fromJson("{" +
" \"Sample\": {" +
" \"tag_description\": \"abc\"," +
" \"tag_category_id\": \"def\"," +
" \"tag_id\": \"ghi\"" +
" }," +
" \"Sample1\": {" +
" \"tag_description\": \"jkl\"," +
" \"tag_category_id\": \"mno\"," +
" \"tag_id\": \"pqr\"" +
" }" +
"}", Map.class);
System.out.println("Map size: " + result.size());
}
}
The resulting size is 2. The map entries are keyed Sample, Sample1, and the values are lists containing the nodes. You can see this using a debugger.

Realm can't create Nested Objects from Json

I've been trying to create a nested RealmObject using a json but it only creates the first Object and not the nested ones. I would appreciate a help on this.
my Realm classes:
Content.java
public class Content extends RealmObject {
private String uuid;
RealmList<ContentDetailModel> ContentDetail;
public Content() {
super();
this.uuid = UUID.randomUUID().toString();
}
public String getUuid() {
return uuid;
}
public RealmList<ContentDetailModel> getContentDetails() {
return ContentDetail;
}
public void setContentDetails(RealmList<ContentDetailModel> contentDetails) {
this.ContentDetail = contentDetails;
}
}
ContentDetailModel.java:
public class ContentDetailModel extends RealmObject {
String FileName;
String ContentTypeID;
RealmList<ContentDetailMetadataModel> ContentDetailMetadata;
RealmResults<Content> content = null;
public String getFileName() {
return FileName;
}
public void setFileName(String fileName) {
FileName = fileName;
}
public String getContentTypeID() {
return ContentTypeID;
}
public void setContentTypeID(String contentTypeID) {
ContentTypeID = contentTypeID;
}
public RealmList<ContentDetailMetadataModel> getContentDetailMetadata() {
return ContentDetailMetadata;
}
public void setContentDetailMetadata(RealmList<ContentDetailMetadataModel> contentDetailMetadataz) {
this.ContentDetailMetadata = contentDetailMetadataz;
}
}
and the rest of nested classes are like these. my Json string is as follows:
"
{
"Content":{
"ContentDetail":[
{
"FileName":"test.mp3",
"ContentTypeID":3,
"ContentDetailMetadata":{
"Metadata":[
{
"ID":2,
"Value":"2017-08-02 09:40:30"
},
{
"ID":1,
"Value":"35.73876557934912,51.50785446166992"
}
]
}
},
{
"FileName":"2.jpg",
"ContentTypeID":2,
"ContentDetailMetadata":[
{
"Metadata":{
"ID":2,
"Value":"2017-08-02 09:40:30"
}
},
{
"Metadata":{
"ID":1,
"Value":"35.73876557934912,51.50785446166992"
}
}
]
}
]
}
}
"
and the code I use to do it is :
realm.createObjectFromJson(json)

{
"Content":{
"ContentDetail":[
{
"FileName":"test.mp3",
"ContentTypeID":3,
"ContentDetailMetadata":[{
"Metadata":[
{
"ID":2,
"Value":"2017-08-02 09:40:30"
},
{
"ID":1,
"Value":"35.73876557934912,51.50785446166992"
}
]
}]
},
Translates to:
public class Root extends RealmObject {
private Content Content;
}
public class Content extends RealmObject {
private RealmList<ContentDetail> ContentDetail;
#LinkingObjects("Content")
private final RealmResults<Root> roots = null;
}
public class ContentDetail extends RealmObject {
private String FileName;
private long ContentTypeID;
//private ContentDetailMetadata ContentDetailMetadata;
private RealmList<ContentDetailMetadata> ContentDetailMetadata;
#LinkingObjects("ContentDetail")
private final RealmResults<Content> contents = null;
}
public class ContentDetailMetadata extends RealmObject {
private RealmList<Metadata> Metadata;
#LinkingObjects("ContentDetailMetadata")
private final RealmResults<ContentDetail> contentDetails = null;
}
public class Metadata extends RealmObject {
private long ID;
private String Value;
#LinkingObjects("Metadata")
private final RealmResults<ContentDetailMetadata> contentDetailMetadatas = null;
}
If your schema doesn't look like that, then createOrUpdateFromJson() won't work.
Personally I would advise against using this schema though, it's pretty bad as a Realm schema. It's advisable to parse the JSON and then map it into a schema that makes more sense!

It looks like your JSON has put all fields for the Content object under the Context JSON object instead of directly under the top-level object where it should be.
If you do this, it should work:
realm.createObjectFromJson(Content.class, json.getJSONObject("Content"));

JSON parsing through GSON returns null values

I am trying to read the values of a JSON output.
This is the JSON output:
{"nameOfSummoner":{"id":56529189,"name":"test","profileIconId":550,"summonerLevel":30,"revisionDate":1422110739000}}
And with the following code I am trying to read it:
final Connector connector = new Connector();
String response = connector.connect("link"); // (Returns a String value of the JSON)
final Gson gson = new Gson();
final Summoner summoner = gson.fromJson(response, Summoner.class); //Summoner is a model class
System.out.println(summoner);
Summoner class:
public class Summoner {
private String name;
private long profileIconId;
private long summonerLevel;
private long revisionDate;
public String getName() {
return name;
}
public void setName(final String name) {
this.name = name;
}
public long getProfileIconId() {
return profileIconId;
}
public void setProfileIconId(final long profileIconId) {
this.profileIconId = profileIconId;
}
public long getSummonerLevel() {
return summonerLevel;
}
public void setSummonerLevel(final long summonerLevel) {
this.summonerLevel = summonerLevel;
}
public long getRevisionDate() {
return revisionDate;
}
public void setRevisionDate
(long revisionDate) {
this.revisionDate = revisionDate;
}
#Override
public String toString() {
return "Summoner{" +
"name='" + name + '\'' +
", profileIconId=" + profileIconId +
", summonerLevel=" + summonerLevel +
", revisionDate=" + revisionDate +
'}';
}
}
And I get the following output on the console:
Summoner{name='null', profileIconId=0, summonerLevel=0, revisionDate=0}
I have sadly no idea why this happens. Any help I get is appreciated. I am fairly sure it has to do with the JSON output that "nameOfSummoner" is on top and maybe that's why it does not read what is below.

As mentioned by #PeterMmm , your input is a map with 1 key-value pair.
You need to Create another POJO with Summoner object as attribute:
public class Sample {
private Summoner nameOfSummoner;
//getters and setters
}
and then try parsing. Or, you could create a Map and parse.
Map<String, Summoner> responseObj = new HashMap<String, Summoner>();
responseObj= gson.fromJson(response, responseObj.class);
Summoner obj = responseObj.get("nameOfSummoner");
You will also need to have "id" attribute in Summoner class I believe, else gson will throw an exception.