clone.java

/*
Implementing a clone method

last update: 2022 Dec 13
*/

public SinglyLinkedList<E> clone( ) throws CloneNotSupportedException {
  
  // always use inherited Object.clone( ) to create the initial copy
  SinglyLinkedList<E> other = (SinglyLinkedList<E>) super.clone( ); // safe cast
  
  if (size > 0) { // we need independent chain of nodes
    other.head = new Node<>(head.getElement( ), null);
    Node<E> walk = head.getNext( ); // walk through remainder of original list
    Node<E> otherTail = other.head; // remember most recently created node
    
    while (walk != null) { // make a new node storing same element
      Node<E> newest = new Node<>(walk.getElement( ), null);
      otherTail.setNext(newest); // link previous node to this one
      otherTail = newest;
      walk = walk.getNext( );
    }
  }
  return other;
  
}