title: Convert JSON string to plain key value pair for logging
body: <p>I have a JSON string, where consist of structure something like below, basically I have a chain of VO's and each VO will have list of VO's and Map of VO's as well.</p>
  
  <h2>sample:</h2>
  
  <pre><code>"MessageHeader": {
      "type": "new",
      "id": 10,
      "add_record": "true",
  },
  "MessageBody": {
      "dob_required": false,
      "dept_name": "Purchase",
      "group": {
          "main_group": "main group",
          "sub_group": "sub group"
      },
      "family_info": {
          "person1": {
              "name": "HisName",
              "gender": "male",
              "age": "31",
              "office_info_present": {
                  "office_name": "present office",
                  "office_address": "some address"
                  "some_other_vo":{
  
                  },
              },
              "office_info_previous": {
                  "office_name": "old office",
                  "office_address": "some address"
              },            
          },
          "person2": {
              "name": "HerName",
              "gender": "Female",
              "age": "25",
          }
      },
      "active":true
  }
  </code></pre>
  
  <p>I want to print each and every attribute name and its value in key value pair. I don't want to print the VO name, rather just the end attributes (leaf level attributes)</p>
  
  <h2>like below string:</h2>
  
  <p>type=new id=10 add_record=true dob_required=false dept_name=purchase main_group="main group" sub_group="sub group" name=HisName gender=male age=31 .... name=HerName gender=Female age=25</p>
  
  <p>How this can be done? I would prefer if it can be done using jackson. Otherwise also fine.</p>