Problem 1 The following Java implementation of a class Node

Problem #1: The following Java implementation of a class Node is given:

private class Node<Object>
{
    Node() { this(null, null);
}
    Node(Object d)
{
      this(d, null);
}
Node(Object d, Node n)
{
      data = d;
      next = n;
}
Object data;
Node next;
}

Assume that a singly linked list is implemented with a header node, but no tail node, and that it maintains only a reference to the header node. Using the class Node described above, write a MySingleLinkedList class in Java includes methods to:
(a)
int size()
- return the size of the linked list.
(b)
void print()
- print the linked list.
(c)
boolean contains(Object x)
- test if a value x is contained in the linked list.
(d)
boolean add(Object x)
- add a value x if it is not already contained in thelinked list.
(e)
boolean remove(Object x)
- remove a value x if it is contained in the linked list.

Solution

package mysinglelinkedlist;

public class MySingleLinkedList<Object> {

private Node<Object> head;

/* a.) return the size of the linked list. */

public int size(){

int length=0;

Node<Object> tmp = head;

while(true){

if(tmp == null){

break;

}

length++;

tmp = tmp.next;

}

return length;

}

  

/* b.) print the linked list. */

public void print(){

Node<Object> tmp = head;

while(true){

if(tmp == null){

break;

}

System.out.println(tmp.data);

tmp = tmp.next;

}

}

  

/* c.) test if a value x is contained in the linked list.*/   

public boolean contains(Object x){

Node<Object> tmp = head;

while(tmp!=null)

{

if(tmp.data!=x){

tmp = tmp.next;

}

else{

return true;

}

}

return false;

}

  

/* d.) add a value x if it is not already contained in thelinked list. */

public boolean add(Object element){

Node<Object> nd = new Node<Object>();

nd.data = element;

System.out.println(\"Adding: \"+element);

/**

* check if the list is empty

*/

if(head == null){

//since there is only one element, head

head = nd;

return true;

}

else {

boolean flag= contains(element);

if(flag==false){

head.next=nd;   

return true;

}

else {

return false;

}

}

}

  

/* e.) remove a value x if it is contained in the linked list.*/

public boolean remove(Object x){

if(head == null){

System.out.println(\"Underflow...\");

return false;

}

Node<Object> tmp = head;

head = tmp.next;

if(head == null){

head.next = null;

}

System.out.println(\"Deleted: \"+tmp.data);

return true;

}

  

/**

* @param args the command line arguments

*/

public static void main(String[] args) {

MySingleLinkedList<Integer> sl = new MySingleLinkedList<Integer>();

sl.add(3);

sl.add(32);

sl.add(54);

sl.remove(32);

sl.print();

}

  

}

class Node<Object>

{

Node() { this(null, null);

}

Node(Object d)

{

this(d, null);

}

Node(Object d, Node n)

{

data = d;

next = n;

}

Object data;

Node next;

}