This is a incomplete implementation of class TheList in Java. TheList object is a singly-linked list. Where the first node is referenced by the var head, and the last node is referenced by the var tail.

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class ListNode{

public ListNode(E data, ListNode next){

this.data = data;

this.next = next;

}

public E data;

public ListNode next;

}

class TheList implements List{

...

private ListNode head, tail;

}

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Create a class name theDerivedList in Java that extends theList, overriding the method add(element) in the way shown below:

it adds element into the end of the list only if element was not found in the list and no doing anything if the same element was found.