How to convert json object to java classes - 02 (Advanced Option)

I'm Tring to using bellow json String 
(Ref - json.org )

{
 "glossary": {
  "title": "example glossary",

  "GlossDiv": {

   "title": "S",
   "topic": "SsS",

   "GlossList": {

    "GlossEntry": {

     "ID": "SGML",
     "SortAs": "SGML",
     "GlossTerm": "Standard Generalized Markup Language",
     "Acronym": "SGML",
     "Abbrev": "ISO 8879:1986",

     "GlossDef": {
      "para": "A meta-markup language, used to create markup languages such as DocBook.",
      "GlossSeeAlso": ["GML", "XML"]
     },

     "GlossSee": "markup"
    }
   }
  }
 }
}

You can validate this json String using JsontLint


Now I'm going to create relevent java classes. This is very easy when use jsonschema2pojo .

Paste above JSON String space of jsonschema2pojo space.
(Follow bellow image)

You can preview All java classes using click priview button.You can downlord it clicking zip button and classname-source.zip link.

I created Spring Boot test Project

Package Name - com.example.demo
(Because aboue jsonschema2pojo I used com.example.demo.pojo)

Now I can copy downloaded json classes to the com.example.demo package.

Follow package structure 

Add jackson dependencies to the pom.xml file

<dependency>
   <groupId>com.fasterxml.jackson.core</groupId>
   <artifactId>jackson-databind</artifactId>
</dependency>

Create WelcomController class

package com.example.demo.pojo;

import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class WelcomeController {
 
 @RequestMapping(value = "/jsontopojo", method = RequestMethod.POST )
 public @ResponseBody Example value(@RequestBody Example example){
  return example;
  
 }

}

Now run the project and use ARC or Postman client to request.

url - http://localhost:8080/jsontopojo

method -POST

body - Add to above json string

If You need to return some string of request json body,

package com.example.demo.pojo;

import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class WelcomeController {
 
 @RequestMapping(value = "/jsontopojo", method = RequestMethod.POST )
 public @ResponseBody String value(@RequestBody Example example){
  return example.getGlossary().getTitle();
  
 }

}

You can see return  "example glossary".

Again Simple Example without using jsonschema2pojo site.

Follow bellow json string

{
 "car": {
  "title": "example glossary",

  "bmw": {

   "title": "S",
   "topic": "SsS"

  }
 }
}

Create  Main class

package com.example.demo.pojo;

import com.fasterxml.jackson.annotation.JsonProperty;

public class JsontoPojo {
 
 @JsonProperty("car")
 private Car car;

 public Car getCar() {
  return car;
 }

 public void setCar(Car car) {
  this.car = car;
 }
}

Create Car class

package com.example.demo.pojo;

import com.fasterxml.jackson.annotation.JsonProperty;

public class Car {
 
 @JsonProperty("title")
 private String title;
 
 @JsonProperty("bmw")
 private BMW bmw ;
 
 public String getTitle() {
  return title;
 }
 public void setTitle(String title) {
  this.title = title;
 }
 public BMW getBmw() {
  return bmw;
 }
 public void setBmw(BMW bmw) {
  this.bmw = bmw;
 }
 
 

}

Create BMW class

package com.example.demo.pojo;

import com.fasterxml.jackson.annotation.JsonProperty;

public class BMW {
 
 @JsonProperty("title")
 private String title;
 
 @JsonProperty("topic")
 private String topic;
 
 public String getTitle() {
  return title;
 }
 public void setTitle(String title) {
  this.title = title;
 }
 public String getTopic() {
  return topic;
 }
 public void setTopic(String topic) {
  this.topic = topic;
 }
 
 
 

}

Create  Main class

package com.example.demo.pojo;

import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class WelcomeController {
 
 
 @RequestMapping(value="/car" , method = RequestMethod.POST)
 public @ResponseBody JsontoPojo type(@RequestBody JsontoPojo jsontoPojo){
  return jsontoPojo;
 }

}

URL - http://localhost:8080/car


Thank You


Others

@JsonIgnoreProperties

https://dzone.com/articles/jackson-annotations-for-json-part-1-serialization

@JsonProperty

https://dzone.com/articles/jackson-annotations-for-json-part-4-general