write a program in java to get the size of ArrayList without using size() method.

To get the size of ArrayList we can use the library  method size() ,but here requirement is not to use the size() method. so that we can use Iterator to get the size of ArrayList. the logic to get the size of ArrayList is simple.

1. First add the element in ArrayList using add() method.
2. Now take an Iterator to iterate the ArrayList one by one.the code to do that is following..     

Iterator itr=al.iterator();      while(itr.hasNext())      {        itr.next();        count++;      }

  

     3. By increasing the count we can get the size of ArrayList. because when              itr.next() will call it will access the element one by one and at that time

        count will also increase.

    4. finally we will get the size of ArrayList.

The code is following to do that-

import java.util.ArrayList;

import java.util.Iterator;

class  ArrayListSize

{

          public static void main(String[] args)

          {

                   int count=0;

                   ArrayList al=new ArrayList<>();

                   al.add(10);

                   al.add(20);

                   al.add(30);

                   al.add(40);

                   al.add(50);

                   System.out.println("Size of ArrayList ::"+al.size());

                   Iterator itr=al.iterator();

                   while(itr.hasNext())

                   {

                             itr.next();

                             count++;

                   }

                   System.out.println("Size of ArrayList ::"+count);

          }

}

Output: