title: JSON Format for map
body: <p>How to create json string for the below format</p>
  
  <pre><code>    Map&lt;String, Map&lt;String, Map&lt;String ,Map&lt;String, Set&lt;VirtualNE&gt;&gt;&gt;&gt;&gt;
  </code></pre>
  
  <p>where VirtualNE is a DTO class</p>
  
  <pre><code> public class VirtualNE {
  
  private VirtualNePK primaryKey;
  private String status;
  private String lockId;
  private String frequency1;
  private String frequency2;
  
       getter &amp; setter goes here
   }
  </code></pre>
  
  <p>where VirtualNePK as primarykey class nested inside VirtualNE dto class</p>
  
  <pre><code>public class VirtualNePK {
  private String pCode;
  private String neType;
  private String src;
  private String destination;
  
    getter &amp; setter goes here
   }
  </code></pre>