How to use Jackson Package in this scenario?

Question

Hi I have a Json like follows:

A {
    B {
        C [{
            x1:x2,
            y1:y2
          }]
       }
  }

Now my requirement is to convert the A, B, C to camelCase notation(as required) which I did by using @JsonProperty and getter and setter methods for the respective POJO class.

Finally, my output is as follows:

a {
    b {
        c [{
            x1:x2,
            y1:y2
          }]
       }
  }

Now I want to add a new empty object like d between b and c.

Can you please help me in appending a new empty JSON object.

The required output should be something like this:

Json :

"Skills" : {
  "SkillSet" : [ 
    {
        "Skill" : "Management"
    },
    {
        "Skill" : "IT"
    }, 
  ]
}

I need something like this:

"skills" : {
  "mainSkills" {
     "skillSet" : [ 
       {
        "Skill" : "Management"
       },
       {
        "Skill" : "IT"
       }, 
     ]
   }
}

I'm done with converting the camelCase but I need to insert the new object "mainSkills".

Map your source JSON to Java classes (let's call them A). Map your target JSON to Java classes (let's call them B). Parse your source JSON to A, transform A to B, and write B as JSON. — JB Nizet, Aug 16 '17 at 12:36

cassiomolin · Accepted Answer · 2017-09-08T09:19:59.670

The following will give you the expected output:

String json = "{\n" +
              "  \"skills\": {\n" +
              "    \"skillSet\": [\n" +
              "      {\n" +
              "        \"skill\": \"Management\"\n" +
              "      },\n" +
              "      {\n" +
              "        \"skill\": \"IT\"\n" +
              "      }\n" +
              "    ]\n" +
              "  }\n" +
              "}";

// Create ObjectMapper instance to parse the JSON
ObjectMapper mapper = new ObjectMapper();

// Parse the JSON into the Jackson tree model
JsonNode tree = mapper.readTree(json);

// Store a reference to the "skills" node
JsonNode skills = tree.get("skills");

// Store a reference to the "skillsSet" node
JsonNode skillSet = skills.get("skillSet");

// Remove the "skillsSet" node from the tree
((ObjectNode) skills).remove("skillSet");

// Create the "skillSet" node under "mainSkills" 
// and sets it under the "skills" node
((ObjectNode) skills).set("mainSkills", 
        mapper.createObjectNode().set("skillSet", skillSet));

// Write the tree as a JSON string using the default pretty printer
String newJson = mapper.writerWithDefaultPrettyPrinter().writeValueAsString(tree);

If you don't want to manipulate the JSON as demonstrated above, follow the JB Nizet approach.

Thank you so much. It is working as expected...All I need to learn about the code which you did step by step. — Pavan, Aug 17 '17 at 06:03

How to use Jackson Package in this scenario?

1 Answers1