title: JSON Parsing and returning hash map
body: <p>I have a sample json string in the format below </p>
  
  <pre><code>{
      "sample":{
          "1":{
              "a":100,
              "b":101
  
          },
          "2":{
              "a":200,
              "b":101
          },
          "3":{
              "a":100,
              "b":102
          }
      }
  }
  </code></pre>
  
  <p>Is there a way to retreive the data in the format                                                       Map(String,Map  (String,Integer)).    In the inner map I need only the first element "a". I understand we can define a new class structure and get the data and get the same transformed through ObjectMapper, which is not requirement in my case.Appreciate the help.</p>