Iterators

• Iterator is an interface that is available in the Java collection framework which is in java.util package.
• It is used to iterate over a collection of objects.
• It will traverse the collection of elements one by one
• It has been added to Java in version 1.2
• It has Read and Remove operations

Iterator Methods

• boolean hasNext(): return true if there is a element after current element else false
• Object next(): Returns the next element. if there are nothing throws an exception
• void remove(): Removes current element.

Example

import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;

public class ExternalIteratorDemo {

    public static void main(String[] args) {

        List<String> cities = new LinkedList<>();

        cities.add("chennai");
        cities.add("kolkata");
        cities.add("banglore");
        cities.add("vizag");

        Iterator<String> cityIterator = cities.iterator();

        while(cityIterator.hasNext()){
        System.out.println(cityIterator.next());
        }
    }
}

check result here