Interview

In this post, we will see Spring interview interview questions. If you are java/j2ee developer and have some experienced on Spring, you are going to face Spring interview questions. If you are looking for below queries then this post will help you as well. Spring interview questions for 3 years experience Spring interview questions for […]

In this post, we will see interview questions on java String. String is most important data type which we use in our programs very often. 1. Why String is declared final or immutable in java? There are various reasons to make String immutable. String pool Thread Safe Security Class Loading Cache hash value You can […]

Core java interview questions play a vital role in java/j2EE interviews. Whether you are fresher or experienced, you are going to face core java interview questions. You can also go through top java interview programs for practicing java programs. Here I am providing some important core java interview questions with answers. 1. What do you […]

In this post, we will see difference between CountDownLatch and CyclicBarrier in java. Lets first see similarities among them. Both wait for specific number of threads or tasks to finish. Lets see differences between CountDownLatch and CyclicBarrier. CountDownLatch vs CyclicBarrier Parameter CountDownLatch CyclicBarrier Reuse It can not be reused once count reaches 0 It can […]

Web services interview questions are most asked questions if you are applying for software developer role. In this post, we will see multiple web services interview questions. 1. What are web services? Web services are ways of communication between two application over network. It allows you to expose business logic using API. For example: Lets […]

Restful web services are very popular now a days because it is very simple to implement and less time consuming. In this post, we are going to see restful web services interview questions with answers. 1. What is REST? REST is an architectural style which was brought in by Roy Fielding in 2000 in his […]

In this post, I am going to share some of logical java Collections interview questions which will help to understand Collections concepts better. For an extensive list of java programs, please go to Java interview programs. Question 1: What can be output of below code : [crayon-67681a4083a54669584726/] options are :  A)France France India B)India India […]

As per java docs, CountDownLatch is synchronisation aid that allows one or more threads to wait until set of operations being performed in other threads completes.

ConcurrentHashMap was introduced in Java 5 with other concurrency utils such as CountDownLatch, CyclicBarrier and BlockingQueue. ConcurrentHashMap in java is very similar to HashTable but it provides better concurrency level. You might know , you can synchonize HashMap using Collections.synchronizedMap(Map). So what is difference between ConcurrentHashMap and Collections.synchronizedMap(Map)In case of Collections.synchronizedMap(Map), it locks whole HashTable […]