title: How linkedhashmap maintains insertion order
body: <p>I know how Hashmap works internally. Linkedhashmap is extending Hashmap class. So how Linkedhashmap is able to maintain the insertion order. I have read the javadoc for Linkedhashmap, but it does not have any details about this. Can somebody help me understand this?  </p>
  
  <p>Thanks in advance.</p>