Interview Questions and Answers for 'T' | Search Interview Question

Interview Questions and Answers - Order By Newest

Q511. Difference between Base Class, Derived Class , Abstract Class and Concrete Class ?

Ans. Base Class is a relative term used to signify the Parent class in Parent - Child or Base - derived relationship.

Derived Class is a relative term used to signify the Child class in Parent - Child or Base - derived relationship.

Abstract Class is a class that is not allowed to be instantiated and hence can serve only a base class for it's usage.

Concrete Class is the class which is supposed to be instantiated and hence provide definition for all implementing interface methods and extending abstract methods.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve Base Class Derived Class Abstract Class Concrete Class}

Q512. Which AWS computing service provides IAAS, PAAS , Containerization and Serverless ?

Amazon Web Services (AWS)

Ans. EC2 is IAAS
Elastic Beanstalk is PAAS
EKS is Containerization service
Lambda is Serverless

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve IAAS PAAS Containerization Serverless}

Q513. What are the advantages and disadvantages of using Lambda over EC2 ?

Amazon Web Services (AWS)

Ans. Advantages -

Much Cheaper
Continuous scaling
Higher level and Serverless

Disadvantages -

Warm up time
Limited flexibility in terms of technologies
Limited control

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve aws lambda aws serverless computing amazon cloud serverless computing amazon lambda aws ec2 aws computing amazon cloud computing amazon ec2}

Q514. Can we associate a single EFS volume with multiple EC2 instances ?

Amazon Web Services (AWS)

Ans. Yes

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve aws efs volume aws ec2 aws computing amazon cloud computing amazon ec2}

Q515. What are the different trigger types in AWS Lambda ?

Amazon Web Services (AWS)

Ans. Api Gateway
Alexa
CloudFront
CloudWatch
Code Commit
Kinesis
S3
SNS

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve aws lambda aws serverless computing amazon cloud serverless computing amazon lambda trigger}

Q516. Why AWS named the DNS service as Route 53 ?

Amazon Web Services (AWS)

Ans. Route is for routing which is the purpose of DNS and Default port for DNS is 53

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve aws route53}

Q517. What happens to backups if we delete the RDS instance ?

Amazon Web Services (AWS)

Ans. Automated Backups are deleted automatically whereas Snapshots are preserved. Upon terminating RDS instance , AWS gives a warning about that and requests to create a final snapshot before terminating the instance.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve aws rds aws database amazon cloud database}

Q518. Describe best practices with respect to AWS security groups ?

Amazon Web Services (AWS)

Ans. Configure it while creating EC2 instance only

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve aws security groups Asked in 1 Companies}

Q519. How would you secure EC2, Volume and Snapshots in Cloud ?

Amazon Web Services (AWS)

Ans. Adding more security group, it works like a firewall

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve aws ec2 aws computing amazon cloud computing amazon ec2 aws ebs volume snapshot Asked in 1 Companies}

Q520. What is mounting in AWS ?

Amazon Web Services (AWS)

Ans. Attaching Volumes ( EBS / EFS ) on AWS Computing ( EC2, EKS )

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve aws ebs aws efs aws ec2 aws computing amazon cloud computing amazon ec2 aws eks}

Q521. Can we have internal or private ELB as origin in cloudfront ?

Amazon Web Services (AWS)

Ans. No, it should be public as cloudfront doesn't have a way to access private ELB.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve aws elb amazon elb aws cloudfront amazon cloudfront}

Q522. Difference between NAT Instances and NAT Gateway

Amazon Web Services (AWS)

Ans. High bandwidth and availability in NAT Gateway
NAT Gateway is completely managed by AWS
NAT Gateway is auto scalable
NAT Instance is just like EC2 instance and hence backed by security group
NAT Instance can be used as bastion host whereas NAT Gateway cannot be.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve aws nat instance aws nat gateway}

Q523. When singleton can break and how to resolve it

Design

Ans. Deserialization. In serialization, we can save the object of a byte stream into a file or send over a network. Suppose if you serialize the Singleton class, and then again de-serialize that object, it will create a new instance, hence deserialization will break the Singleton pattern.

To overcome this issue, we need to override readResolve() method in the Singleton class and return the same Singleton instance.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve singleton design patterns Asked in 1 Companies}

Q524. why string pool concept for only String but not for StringBuffer ?

Core Java

Ans. As String is immutable so by maintaining pool area we can refer the object to same area if they are with same content. But when it comes to string buffer or builder then due to mutable property if we do so then all the objects referring to that area will from now has new content.. So as to avoid this pool is present only in string.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve Asked in 1 Companies}

Q525. why string pool concept for only String but not for StringBuffer ?

Core Java

^{This question was recently asked at 'oodles technology'.This question is still unanswered. Can you please provide an answer.}

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve Asked in 1 Companies}

Q526. What are different ways a user can be authenticated other than username / password ?

Authentication

Ans. IP Authentication
IP Range Authentication
Certificates
Authentication Cards

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve}

Q527. Difference between List and LinkedList ?

Core Java

Ans. A List is an child interface of collection interface in java where as Linked list is and implementation class of List interface which has doubly linked as a underlying data structure

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve linkedlist list vs linkedlist Asked in 1 Companies}

Q528. How to track immediate parent of the child in selenium using xpath?

Selenium

Ans. Using ./

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve Asked in 1 Companies}

Q529. If you are given choice to either load object eagerly or lazily , which one would you use in case of singleton pattern ?

Design

Ans. I would choose Eager as the cost for 1 additional object is too minute for any such consideration.

Eager Loading results in Faster access ( Object available at load time) at the cost of additional space.

Lazy loading results in space saving ( Object available at first use ) at the cost of access speed.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve design Pattern Singleton Lazy vs Eager Loading}

Q530. Is Google App Engine , IAAS, PAAS or SAAS ?

Google Cloud Platform (GCP)

Ans. It's PAAS ( Platform as a service )

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve Google App Engine}

Q531. Why would a cloud customer use resources in multiple regions and zones ?

Cloud Computing

Ans. 1. Fault Tolerance
2. Better Access by bringing the application closer to the users.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve Google Cloud Computing (GCP) Amazon Web Services (AWS) Availability Zones Regions and Zones Infrastructure}

Q532. Have you ever heard about csrf attacks ?

Security

Ans. Yes, Cross-Site Request Forgery (CSRF) is an attack that forces an end user to execute unwanted actions on a web application in which they're currently authenticated.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve csrf attack Cross-Site Request Forgery (CSRF) Asked in 16 Companies}

Q533. Do you think a csrf token should only be generated after authentication ?

Security

Ans. No, they should be created before authentication too

https://cheatsheetseries.owasp.org/cheatsheets/Cross-Site_Request_Forgery_Prevention_Cheat_Sheet.html#login-csrf

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve csrf token csrf attack}

Q534. What is concurrent interface ?

Core Java

Ans. ConcurrentMap is an interface and it is a member of the Java Collections Framework. It represents a Map that is capable of handling concurrent access to it without affecting the consistency of entries in a map. ConcurrentMap interface present in java.util.concurrent package.

HashMap operations are not synchronized, while Hashtable provides synchronization. Though Hashtable is thread-safe, it is not very efficient. To solve this issue, the Java Collections Framework introduced ConcurrentMap in Java 1.5.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve Concurrent Interface java.util.concurrent Java 8 Concurrency java concurrency java 8 Asked in 1 Companies}

Q535. What are system integrators in Cloud Computing?

Cloud Computing

^{This question is still unanswered. Can you please provide an answer.}

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve Amazon Web Services (AWS) Google Cloud Platform (GCP)}

Q536. What is a cookie ?

Java EE

Ans. A cookie is a small piece of text stored on a user's computer by the browser for a specific domain. Commonly used for authentication, storing site preferences, and server session identification.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve cookie javascript web application session management browser j2ee Asked in 16 Companies basic frequent}

Q537. What is servlet Chaining ?

Java EE

Ans. Multiple servlets serving the request in chain.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve java web application servlets Asked in 1 Companies rare}

Q538. Can static method access instance variables ?

Core Java

Ans. Though Static methods cannot access the instance variables directly, They can access them using instance handler.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve static static method java oop variables Asked in 1 Companies basic frequent}

Very frequently asked. Usually asked in this format or as difference with interfaces / concrete classes.

Q539. What is an abstract class ?

Core Java

Ans. Abstract class is the class that is not supposed to be instantiated. The purpose of the class to only have extension to the derived class.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve abstract class Asked in 6 Companies basic frequent}

Q540. Which interface does java.util.Hashtable implement?

Core Java

Ans. Java.util.Map

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve java collections hashtable map basic rare}

Search Interview Questions

Help us and Others Improve. Please let us know the questions asked in any of your previous interview.