iterable java

// Java code to illustrate the use of iterator 
import java.io.*; 
import java.util.*; 
  
class Test { 
    public static void main(String[] args) 
    { 
        ArrayList<String> list = new ArrayList<String>(); 
  
        list.add("A"); 
        list.add("B"); 
        list.add("C"); 
        list.add("D"); 
        list.add("E"); 
  
        // Iterator to traverse the list 
        Iterator iterator = list.iterator(); 
  
        System.out.println("List elements : "); 
  
        while (iterator.hasNext()) 
            System.out.print(iterator.next() + " "); 
  
        System.out.println(); 
    } 
} 

class CustomDataStructure implements Iterable<> { 
      
    // code for data structure 
    public Iterator<> iterator() { 
        return new CustomIterator<>(this); 
    } 
} 
class CustomIterator<> implements Iterator<> { 
      
    // constructor 
    CustomIterator<>(CustomDataStructure obj) { 
        // initialize cursor 
    } 
      
    // Checks if the next element exists 
    public boolean hasNext() { 
    } 
      
    // moves the cursor/iterator to next element 
    public T next() { 
    } 
      
    // Used to remove an element. Implement only if needed 
    public void remove() { 
        // Default throws UnsupportedOperationException. 
    } 
}