JSON Tree Model in Jackson

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In this Tutorials we are going to see how to read and write JSON Tree model using Jackson JsonNode.
The JsonNode is used to read and write tree structured date.It is similar to XML Dom tree.
1. Create project called JSONExample.
2. Create package called com.javatutorialscorner.jackson 
3. add jackson-mapper-asl-1.9.13.jar, jackson-core-asl-1.9.13.jar into build path.
4. Create java class called JacksonTreeExample under com.javatutorialscorner.jackson
JacksonTreeExample.java

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01.package com.javatutorialscorner.jackson;

02. 

03.import java.io.File;

04.import java.io.IOException;

05.import java.util.Iterator;

06. 

07.import org.codehaus.jackson.JsonNode;

08.import org.codehaus.jackson.JsonProcessingException;

09.import org.codehaus.jackson.map.ObjectMapper;

10.import org.codehaus.jackson.node.ObjectNode;

11. 

12.public class JacksonTreeExample {

13. 

14. /**

15.  * @param args

16.  */

17. public static void main(String[] args) {

18.  // TODO Auto-generated method stub

19.  ObjectMapper mapper = null;

20. 

21.  mapper = new ObjectMapper();

22. 

23.  try {

24.   JsonNode root = mapper.readTree(new File(

25.     "C:\\jtc\\javatutorialscorner.json"));

26. 

27.   JsonNode id = root.path("id");

28.   System.out.println("ID : " + id.getIntValue());

29.   JsonNode name = root.path("name");

30.   System.out.println("Name : " + name.getTextValue());

31.   JsonNode list = root.path("list");

32.   Iterator<JsonNode> iterator = list.getElements();

33.   while (iterator.hasNext()) {

34.    JsonNode format = iterator.next();

35.    System.out.println("Format : " + format.getTextValue());

36.   }

37. 

38.   ((ObjectNode) root).put("id", 7);

39.   ((ObjectNode) root).put("name", "Dhoni");

40.   mapper.writeValue(new File("C:\\jtc\\javatutorialscorner.json"),

41.     root);

42.  } catch (JsonProcessingException e) {

43.   // TODO Auto-generated catch block

44.   e.printStackTrace();

45.  } catch (IOException e) {

46.   // TODO Auto-generated catch block

47.   e.printStackTrace();

48.  }

49. 

50. }

51. 

52.}

The javatutorialscorner.json file contains following String

{"id":10,"name":"Tendulkar","list":["Test - 198 ","ODI - 463 ","T20 - 1","IPL - 78"]}

Now run the program see the following output in console.

ID : 10

Name : Tendulkar

Format : Test - 198

Format : ODI - 463

Format : T20 - 1

Format : IPL - 78

and also javatutorialscorner.json File content replace with following contents.

{"id":7,"name":"Dhoni","list":["Test - 198 ","ODI - 463 ","T20 - 1","IPL - 78"]}

Jackson Java JSON 10/12/2013 08:51:00 am