title: Map<String, Map<Object, Object>> how to get the value pair dynamically in java
body: <p>Map data structure : <code>Map&lt;String, Map&lt;Object, Object&gt;&gt;</code></p>
  
  <p>Sample data:</p>
  
  <pre><code>  Key: Data, Value: {AIA=Yes, AppNumber=15671037, AppType=Utility, RegNumber=P01-010785, Class=714/006.210}
  </code></pre>
  
  <p>From the above, I need to take these Keys<code>(AIA, AppNumber, AppTYpe, RegNumber)</code>  dynamically.
  for Map I can able to get it, but I don't know in this inner MAP</p>