JavaMadeSoEasy.com (JMSE): ConcurrentSkipListSet - fail-safe or fail-fast iteration using iterator, listIterator, Enumeration and enhanced for loop

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ConcurrentSkipListSet - fail-safe or fail-fast iteration using iterator, listIterator, Enumeration and enhanced for loop.

iterator returned by ConcurrentSkipListSet is fail-safe. Means any structural modification made to ConcurrentSkipListSet like adding or removing elements during Iteration won’t throw any Exception.

import java.util.Collections;

import java.util.Enumeration;

import java.util.Iterator;

import java.util.Set;

import java.util.concurrent.ConcurrentSkipListSet;

/** Copyright (c), AnkitMittal JavaMadeSoEasy.com */

public class ConcurrentSkipListSetTest {

public static void main(String args[]) {

Set<String> concurrentSkipListSet = new ConcurrentSkipListSet<String>();

concurrentSkipListSet.add("javaMadeSoEasy");

concurrentSkipListSet.add("ankit");

System.out.println("-------use iterator-------");

// fail-safe

Iterator<String> iterator = concurrentSkipListSet.iterator();

while (iterator.hasNext()) {

concurrentSkipListSet.add("newElement1");

System.out.println(iterator.next());

}

System.out.println("-------use Enumeration-------");

// fail-safe

Enumeration<String> listEnum = Collections

.enumeration(concurrentSkipListSet);

while (listEnum.hasMoreElements()) {

concurrentSkipListSet.add("newElement2");

System.out.println(listEnum.nextElement());

}

System.out.println("-------use enhanced for loop-------");

// enhanced for loop is fail-safe

for (String string : concurrentSkipListSet) {

concurrentSkipListSet.add("newElement3");

System.out.println(string);

}

/*OUTPUT

-------use iterator-------

ankit

javaMadeSoEasy

newElement1

-------use Enumeration-------

ankit

javaMadeSoEasy

newElement1

newElement2

-------use enhanced for loop-------

ankit

javaMadeSoEasy

newElement1

newElement2

newElement3

ConcurrentSkipListSet - iterate using iterator, listIterator, Enumeration and enhanced for loop

HashMap - put, get, containsKey , containsValue, remove, size methods

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