Is it possible to implement XOR LinkedList in Java(DLL with single pointer) [duplicate]

Question

XOR linked lists are basically efficient version of linked list which store addresses of previous and next nodes to implement Doubly Linked List using only single pointer. I was wondering if it's possible to implement the in Java, since it doesn't have pointers. In C this could be done by

 /* Insert a node at the begining of the XORed linked list and makes the
    newly inserted node as head */
void insert(struct node **head_ref, int data)
{
    // Allocate memory for new node
    struct node *new_node  = (struct node *) malloc (sizeof (struct node));
    new_node->data = data;

    /* Since new node is being inserted at the begining, npx of new node
       will always be XOR of current head and NULL */
    new_node->npx = XOR(*head_ref, NULL);

    /* If linked list is not empty, then npx of current head node will be XOR 
       of new node and node next to current head */
    if (*head_ref != NULL)
    {
        // *(head_ref)->npx is XOR of NULL and next. So if we do XOR of 
        // it with NULL, we get next
        struct node* next = XOR((*head_ref)->npx,  NULL);
        (*head_ref)->npx = XOR(new_node, next);
    }

    // Change head
    *head_ref = new_node;
}

Answer 1

No, you can't do this in Java at all -- you cannot get the address of an object or compute a reference to an object from other values. This allows the garbage collector to move objects around without interfering with the program.

It's also a really bad idea in C++.

If you're worried about the memory overhead in a linked list, you can store multiple items per node. If a node has prev, next, and items[16] references, and you always make sure your nodes are at least half full, then it will use less memory than an XOR list on average.