What is Iterator
Answer : With release of java JDK 1.2 java.util.Iterator interface been introduced. It allows to iterator over a collection of objects. It provides three methods:
- hasNext() – returns true if the iteration got more elements
- next() – returns next element in iteration
- remove() – removes from collection
Please see example below:
package com.javahonk.iteratortest; import java.util.ArrayList; import java.util.Iterator; public class IteratorTest { public static void main(String[] args) { ArrayList<String> arrayList = new ArrayList<String>(); arrayList.add("A"); arrayList.add("A"); arrayList.add("C"); arrayList.add("B"); arrayList.add("D"); arrayList.add("F"); // Iterator display content System.out.print("Contents of arrayList: "); Iterator<String> itr = arrayList.iterator(); while (itr.hasNext()) { String element = itr.next(); System.out.print(element + " "); } } }
Output:
