Traverse and reverse a linked list takes time complexity of O(n).

Traverse a double linked list requires only node next reference until it reach to trail or null value :

public void traverseLinkedList(){

    Node<T> tempNode = start;

    while (tempNode != null){
        tempNode = tempNode.getNextReference();

        Log.e("value", "" + tempNode.getValue());
    }

}

Reverse a double linked list :

public Node<T> reverseLinkedList(){

    Node<T> temp = null;
    Node<T> current = start;

    while (current.getNextReference() != null){

        if (current == null){
            break;
        }else{
            temp = current.getNextReference();
            current.setNextReference(current.getPrevReference());
            current.setPrevReference(temp);
            current = temp;
        }

    }
    return current;

}