Write a Bag class which implements this API The class mainta

Write a Bag class which implements this API. The class maintains a linked list in LIFO order. Alinked list is a recursive data structure that is either empty (null) or a reference to a node having a generic item and a reference to a linked list.

Here is the beginning of the code to get you started.

public class Bag<Item> implements Iterable<Item> {

private int N; // number of elements in bag
private Node first; // beginning of bag

// linked list class
private class Node {

private Item item;
private Node next;

}

// include:
// check for an empty stack
// code that returns the size of bag
// code for adding item to bag
// test client

If the file tiny.txt contains the following:

S O R T E X A M P L E

then the output would be:

java Bag <tiny.txt
size of bag = 11
E
L
P
M
A
X
E
T
R
O
S

Some basic data types feature collections of objects. In one data type, called Bag, the algorithm collects items and iterates through the collected items. An example of its API is: public class Bag implements Iterable

Solution

public class Bag<Item> implements Iterable<Item> {
private int N; // number of elements in bag
private Node first; // beginning of bag
// linked list class
private class Node {
   private Item item;
   private Node next;
  
   Node(Item item, Node n){
       item = item;
       next = n;
   }
  
   Node(Item item)
   {
   this(item, null);
   }
      
   private Node head;
   private Node last;
  
   public Bag(){
       head = null;
       last = null;
   }
  
   // isempty method
   public boolean isEmpty(){
       return head == null;
   }
  
   public int size()
{
int count = 0;
Node p = first;   
while (p != null)
{
// There is an element at p
count ++;
p = p.next;
}
return count;
}
  
   public void add(Item val)
{
if (isEmpty())
{
first = new Node(val);
last = first;
}
else
{
// Adding to existing list
last.next = new Node(val);
last = last.next;
}
}
}