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Json inside json not working in spring boot

I am trying to use JSON inside a JSON request.
for example:
{
"name":"newdeeeepaajlf",
"category":"fsafaa",
"jsonData":{
"a":"value"
}
}
now when I am trying to get it in my DTO which has
private JSONObject jsonData;
it gets converted in a blank JSON
{}
I am stuck in this.

We can use map to convert the data
public class TestModel {
private String name;
private String category;
private Map<String, Object> jsonObj;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getCategory() {
return category;
}
public void setCategory(String category) {
this.category = category;
}
public Map<String, Object> getJsonObj() {
return jsonObj;
}
public void setJsonObj(Map<String, Object> jsonObj) {
this.jsonObj = jsonObj;
}
}
and use above class from controller like below
#PostMapping("/test")
public boolean test(#RequestBody TestModel model) {
System.out.println(model.getCategory());
System.out.println(model.getName());
JSONObject jsonObj = new JSONObject(model.getJsonObj());
System.out.println(jsonObj);
return true;
}
For request
{
"category":"json",
"name":"name",
"jsonObj": {
"a": "value"
}
}
it will print
json
name
{a=value}

you have a error in json if you have json something like below.
{
"name": "newdeeeepaajlf",
"category": "fsafaa",
"jsonData": {
"a": "value"
}
}
you can use this as a class
public class Codebeautify {
private String name;
private String category;
JsonData jsonDataObject;
// Getter Methods
public String getName() {
return name;
}
public String getCategory() {
return category;
}
public JsonData getJsonData() {
return jsonDataObject;
}
// Setter Methods
public void setName(String name) {
this.name = name;
}
public void setCategory(String category) {
this.category = category;
}
public void setJsonData(JsonData jsonDataObject) {
this.jsonDataObject = jsonDataObject;
}
}
public class JsonData {
private String a;
// Getter Methods
public String getA() {
return a;
}
// Setter Methods
public void setA(String a) {
this.a = a;
}
}
also json within json is working with in spring boot its a very common scenario. use ObjectMapper to map json with class.

Spring Boot - Hierarchical entities data is not returning from a rest API

I have an API method implemented in spring boot for Courses. It fetches the course by topic Id. The Course class is implemented as:
#Entity
public class Course {
#Id
private String id;
private String name;
private String description;
#ManyToOne
private Topic topic;
public Course() {
}
public Course(String id, String name, String description, String topicId) {
super();
this.id = id;
this.name = name;
this.description = description;
this.topic = new Topic(topicId, "", "");
}
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
public void setTopic(Topic t) {
this.topic = t;
}
}
And the API method is implemented as:
#RequestMapping(method=RequestMethod.GET, value="/topics/{topicId}/courses")
public RestMessage getAllCourses(#PathVariable String topicId) {
try {
List<Course> course = courseService.getAllCourses(topicId);
message = new RestMessage(course,StatusCodeEnum.OK);
return message;
} catch (Exception e) {
message = new RestMessage(e.getMessage(),StatusCodeEnum.INTERNAL_SERVER_ERROR);
message.setException(e);
return message;
}
}
The method implementation is simple, it tries to get all the courses based on the topic id and return it as a RestMessage Object. I'm using postman for the testing and in the response I am getting the list of Course but the Topic entity data is discarded.
The api response is as:
{
"data": [
{
"id": "java-streams",
"name": "Java Streams",
"description": "Java Stream learning"
}
],
"httpStatus": "OK",
"statusCode": 200,
"exception": null
}
And the RestMessage Class is defined as:
public class RestMessage {
private Object data;
private StatusCodeEnum httpStatus;
private int statusCode;
private Exception ex;
public RestMessage() {
}
public RestMessage(Object d, StatusCodeEnum c) {
data = d;
httpStatus = c;
statusCode = c.val();
}
public void setData(Object d) {
data =d;
}
public void setHttpStatus(StatusCodeEnum c) {
httpStatus = c;
}
public void setStatusCode(int c) {
statusCode = c;
}
public void setException(Exception e) {
ex = e;
}
public void setStatusCode(StatusCodeEnum c) {
httpStatus = c;
}
public Object getData() {
return data;
}
public StatusCodeEnum getHttpStatus() {
return httpStatus;
}
public Exception getException() {
return ex;
}
public int getStatusCode() {
return statusCode;
}
}
However, I have tried to debug the API endpoint and before returning the RestMessage object I have data in the required shape but after getting the json response the Topic object is truncated for all the courses.
The debug data image is attached:
I wonder what I am doing wrong in this case?

The field topic from Course doesn't have a getter, that's why is ignored by JSON serializer.

You can use Lombok annotation to automatically generate getters and setters.
Just add #Dataon class definition and you will have generated getters and setters, constructor without parameters. You will have everything for what you can said that is POJO class.
Check this link: Project lombok

enum binding exception handling in Spring boot

I have a enum like as:
public enum Age {
THREE("3"),
FIVE("5");
private final String value;
Age(String value) {
this.value = value;
}
public String getValue() {
return value;
}
}
and a User class like:
public class User {
#NotNull
String name;
Age age;
public User() {
}
public User(#NotNull String name, Age age) {
this.name = name;
this.age = age;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Age getAge() {
return age;
}
public void setAge(Age age) {
this.age = age;
}
}
and a RestController like:
#ExceptionHandler(HttpMessageNotReadableException.class)
#ResponseStatus(HttpStatus.BAD_REQUEST)
public ResponseEntity<User> exceptionHandling(HttpMessageNotReadableException exception,
HandlerMethod handlerMethod, WebRequest webRequest) {
logger.error("error:" + exception.getLocalizedMessage());
EnumValidationException ex = (EnumValidationException) exception.getMostSpecificCause();
User user = new User();
user.setName(""); // I want set user's input
user.setAge(Age.FIVE);
return ResponseEntity.ok(user);
}
#ExceptionHandler(MethodArgumentNotValidException.class)
public ResponseEntity<User> exceptionHandling2(MethodArgumentNotValidException exception) {
logger.error("error:" + exception.getLocalizedMessage());
User user = new User();
user.setName(""); // I want set user's input
user.setAge(Age.FIVE);
return ResponseEntity.ok(user);
}
#PostMapping("/user2")
public String setUser2(#Valid #RequestBody User user) {
return "ok";
}
I sed a JSON like:
{
"name":"Name",
"age":"11"
}
now how I handle its HttpMessageNotReadableException exceptions that return Name in name field in response?
should I change enum to static final String?
can I write customized Annotaion? how handle its getValue()?
Note: I use Hibernate.

If I understood your question, you want to print the value of Age, not the
name: in that case, you can try overriding toString() in Age:
#Override
public String toString() {
return value;
}
If you want to use getValue(), you should read the documentation of Spring Boot and especially its underlying JSON API:
https://github.com/FasterXML/jackson
https://github.com/FasterXML/jackson-annotations
https://github.com/FasterXML/jackson-annotations/wiki/Jackson-Annotations

Spring boot REST API Missing URI template variable

I have followed this tutorial to build REST API using Spring boot. It taught alot. But What I am trying to do really got me stuck.
What I am trying to get is:
{
"marks":{
"id":"1",
"name":"test",
"remark":"passed",
"course": {
"id": "1",
"name": "Spring Boot",
"description": "Solves many problems",
"topic": {
"id": "1",
"name": "Java",
"description": "Powerful Programming Language"
}
}
But I get the error when I tried to add the marks- as :
{
"timestamp": 1515600105327,
"status": 500,
"error": "Internal Server Error",
"exception": "org.springframework.web.bind.MissingPathVariableException",
"message": "Missing URI template variable 'courseId' for method parameter of type String",
"path": "/topics/1/courses/1/marks"
}
My Marks Model is:
public class Marks {
#Id
private String id;
private String name;
private String remark;
#ManyToOne
private Course course;
#ManyToOne
private Topic topic;
public Marks() {
}
public Topic getTopic() {
return topic;
}
public void setTopic(Topic topic) {
this.topic = topic;
}
public Marks(String id, String name, String remark,String topicId, String courseId) {
this.id = id;
this.name = name;
this.remark = remark;
this.topic = new Topic(topicId, "","");
this.course = new Course(courseId, " ", " ", " ");
}
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getRemark() {
return remark;
}
public void setRemark(String remark) {
this.remark = remark;
}
public Course getCourse() {
return course;
}
public void setCourse(Course course) {
this.course = course;
}
}
And MarksController.java:
public class MarksController {
#RestController
public class MarksController {
#Autowired
private MarksService marksService;
#RequestMapping("/topics/{topicId}/courses/{id}/marks")
public List<Marks> getAllMarks(#PathVariable String courseId) {
return marksService.getAllMarks(courseId);
}
#RequestMapping(method=RequestMethod.POST, value="/topics/{topicId}/courses{courseId}/marks")
public void addMarks(#RequestBody Marks marks,#PathVariable String topicId ,#PathVariable String courseId) {
marks.setTopic(new Topic(topicId, "", ""));
marks.setCourse(new Course(courseId, "", "", ""));
marksService.addMarks(marks);
}
}
And MarksService.java:
public class MarksService {
#Service
public class MarksService {
#Autowired
private MarksRepository marksRepository;
public void addMarks(Marks marks) {
marksRepository.save(marks);
}
}
And MarksRepository.java:
public interface MarksRepository extends CrudRepository<Marks, String> {
public List<Marks> findByCourseId(String courseId);
public List<Marks> findByTopicId(String topicId);
}
Can anyone help me get the result as in the mentioned JSON.

For the POST method
This:
/topics/{topicId}/courses{courseId}/marks
Should be:
/topics/{topicId}/courses/{courseId}/marks
Note the additional / between courses and {courseId}
For the GET method
This:
/topics/{topicId}/courses/{id}/marks
Should be:
/topics/{topicId}/courses/{courseId}/marks
Note the use of courseId to agree with the parameter name in MarksController.getAllMarks.

Custom JSON response with Spring MVC

Model
public class Organisation {
private String name;
public Organisation() { }
public Organisation(String name) {
this.name = name;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
controller
#RequestMapping(method = RequestMethod.GET)
public List<Organisation> getAll() {
Organisation organisation = new Organisation("google");
List<Organisation> organisations = new ArrayList<>();
organisations.add(organisation);
return organisations;
}
This will give out response like this:
[
{
"name": "google"
}
]
What if we want something like this:
{
"data": [{
"type": "organisations"
"attributes": {
"name": "google"
}
]
}
So how to customize the json. I know that Spring MVC by default uses Jackson to convert models into JSON. Is there a way to customize it. I am trying to send response in JSONApi standard. Also can someone tell how to create links in responses

Create Classes as:
public class Object1 {
private List<Object2> data;
public Object1() {
}
public Object1(List<Object2> data) {
this.data = data;
}
//getters and setters
}
public class Object2 {
private String type;
private Object3 attributes;
public Object2() {
}
public Object2(String type, Object3 attributes) {
this.type = type;
this.attributes = attributes;
}
//getters and setters
}
public class Object3 {
private String name;
public Object3(String name) {
this.name = name;
}
public Object3() {
}
//getters and setters
}
Now your controller method shoul be like:
#RequestMapping(method = RequestMethod.GET)
public Object3 getAll() {
List<Object2> data = new ArrayList<>();
data.add(new Object2("organisations", new Object3("google")));
return new Object1(data);
}