Interview Questions and Answers for 'Mp' | Search Interview Question

Interview Questions and Answers - Order By Newest

Q71. Can we compose the Parent Class object like this ?

class BuggyBread1 extends BuggyBread2 {

private BuggyBread2 buggybread2;

public static void main(String[] args){
buggybread2 = new BuggyBread2();
}
}

Ans. Yes.

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

_{Like Discuss Correct / Improve java composition inheritance yesno}

Try 1 Question(s) Test

Q72. Difference between jar , war and ear ?

Java EE

Ans. Jar is Java Archieve i.e compressed Class or Class / Java files.

War comprises of compressed Servlet class files,JSP FIles,supporting files, GIF and HTML files.

Ear comprise of compressed Java and web module files ( was files ).

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

_{Like Discuss Correct / Improve java j2ee jar web development war ear build management release management Asked in 12 Companies basic frequent}

Q73. What is a package and what are its advantages ?

Core Java

Ans. Package is a namespace that organizes a set of related classes.

Advantages of Packages

1. Better Organization of classes.
2. Saves from the problem of duplicate names as duplicate class names are allowed across different packages.

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

_{Like Discuss Correct / Improve package advantages of packages Asked in 1 Companies Basic}

Q74. What is a self Join and give an example of a self Join ?

or

What is self Join and What is it's purpose ?

Database

Ans. When a Table Join itself , it's a Self Join. For example - we like to know the pair of department names where first dept has lesser employees than the later.

Select D1.name , D2.name from Dept D1, Dept D2 where D1.employee_count < D2.employee_count

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

_{Like Discuss Correct / Improve sql joins self join self-join Pair of employee names with first having lesser salary than later Pair of department names where first dept has lesser employees than the later Asked in 26 Companies basic frequent}

Q75. What are design situations to use Singleton and Prototype Design Pattern ?

Design

Ans. Both are creational design patterns.

Singleton is used when we would like to reuse an object if object is not supposed to hold request or thread specific information. Inversely Prototype is used in situations where we would like to reuse the object information but the request / thread may require it own data to be persisted.

In short, Singleton is used in situations where we can live with single object being shared across multiple requests or threads whereas Prototype is used when we need duplicate copies of objects.

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

_{Like Discuss Correct / Improve design pattern singleton prototype creational design pattrn Asked in 7 Companies expert}

Try 1 Question(s) Test

Q76. Is it a good practice to use Asterick(*) in import statement to load multiple packages with single import statement ?

Core Java

Ans. No, we should be lean in loading only packages which are required. Loading packages which are not being used result in memory overheads.

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

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

Q77. What is a Webdriver ?

Testing

Ans. Selenium WebDriver is a tool for automating web application testing.It helps in replicating the manual tester behavior like keyboard entry, mouse events etc and then matching the output against the expected.

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

_{Like Discuss Correct / Improve selenium webdriver Asked in 37 Companies}

Q78. Find the third last element in a linked list ?

Data Structure

Ans. First Find the number of nodes in the linked list and take it as n.then find the data at n-3 element.

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

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

Q79. What does import java.util.* means in java ?

Core Java

Ans. It means import all the classes and interfaces within java.util package and make them available to use within the current class or interface. This is shorthand wild card annotation for importing all classes within a particular package. This won't import the classes within the sub packages of java.util.

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

_{Like Discuss Correct / Improve java import import statement}

Q80. What is abstraction ?

Design

Ans. Abstraction is a process of hiding the implementation details and describing only the functionality to the user.

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

_{Like Discuss Correct / Improve bstraction oops concepts oops principle Asked in 22 Companies}

Q81. What are the reasons to choose between reserved and on demand instances ?

Server

Ans. In terms of compute options and configurations, Reserved Instances and On Demand instances are the same. The only difference between the two is that a Reserved Instance is one you rent (reserved) for a fixed duration, and in return you receive a discount on the base price of an On Demand instance.

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

_{Like Discuss Correct / Improve aws aws ec2 aws computing amazon cloud computing amazon ec2 production support Google Cloud Platform (GCP)}

Q82. Can you explain the integration between API Gateway and Lambda if we wish to develop services using these tools.

Amazon Web Services (AWS)

Ans. We can create API gateway and give the name of lambda function in order to be linked with lambda function, deploy the API and whenever request will be made from API it will directly be linked to lambda function to perform further process.

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

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

Q83. Why do we need to specify import statement ? Don't you think Java could have been designed in such a way to automatically import everything that's in the class path ?

Core Java

Ans. Java could design it in such a manner but would result in ambiguity if there are multiple files with the same name. The only way to get over it to show the message when you use any such class to provide explicit import with the package prefix. The other problem could be that Java might have to change the early import to Late import and check what's being used to decide what needs to be imported as otherwise you will see errors regarding the ambiguous imports with duplicate file name.

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

_{Like Discuss Correct / Improve import expert}

Q84. Does use of Final class enforces composition over Inheritance in Java ?

Core Java

Ans. Yes, to a certain extent. But the objective for Final class could be beyond just enforcing composition as certain classes might have been created without inheritance or composition in mind.

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

_{Like Discuss Correct / Improve final class composition object oriented programming (oops) oops concepts inheritance object oriented programming (oops) oops concepts composition object oriented programming (oops) oops concepts vs inheritance object oriented programming (oops) oops concepts expert}

Q85. What would you do if you see an error thrown by a lambda function as "Access Denied" while doing something with S3 ?

Amazon Web Services (AWS)

Ans. Just like people , AWS resources too have execution roles or permissions. Seems like in such a situation Lambda function may not have sufficient privileges to perform operations on S3. For example - The execution role of Lambda may just have read permissions on S3 and we may be trying to perform PutObject operation.

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

_{Like Discuss Correct / Improve aws s3 aws storage amazon cloud storage amazon s3 aws lambda aws serverless computing amazon cloud serverless computing amazon lambda}

Q86. What are the drawbacks of using Spot EC2 instances ?

Amazon Web Services (AWS)

Ans. You cannot reserve the time slot and they can be made to use whenever they are available.

AWS can Terminate the EC2 instance on their own even if it's in use.

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 ec2 aws computing amazon cloud computing amazon ec2 spot}

Q87. What are the things to consider while provisioning computing in AWS ?

Amazon Web Services (AWS)

Ans. Service ( EC2, Lambda etc )
AMI ( Operating System and Softwares )
Instance Type ( T,M, R etc )
EBS ( Volume Type , Size )
Price Class ( OnDemand, Dedicated etc )

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

_{Like Discuss Correct / Improve aws computing}

Q88. What is the purpose of EC2 Health check ?

Amazon Web Services (AWS)

Ans. We can use this check for variety of things -

1. Monitoring the status / Alarms in case it's down
2. Regulating traffic to healthy instances only through Load Balancer

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}

Q89. 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}

Q90. 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}

Q91. 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}

Q92. 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}

Q93. 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}

Q94. 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}

Q95. 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)}

Q96. What are transient variables in java?

Core Java

Ans. Transient variables are variable that cannot be serialized.

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

_{Like Discuss Correct / Improve java serialization transient Asked in 15 Companies intermediate rare}

Q97. Explain Inner Classes ?

Core Java

Ans. The accessibility (public, protected, etc.) of the inner class is defined by the outer class.

Just like top-level classes, an inner class can extend a class or can implement interfaces.

Similarly, an inner class can be extended by other classes, and an inner interface can be implemented or extended by other classes or interfaces.

An inner class can be declared final or abstract.Inner classes can have inner classes, but you will have a hard time reading or understanding such complex nesting of classes.

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

_{Like Discuss Correct / Improve java oops classes inner classes Asked in 2 Companies Basic frequent}

Try 2 Question(s) Test

Q98. Why is Java considered Portable Language ?

Core Java

Ans. Java is a portable-language because without any modification we can use Java byte-code in any platform(which supports Java). So this byte-code is portable and we can use in any other major platforms.

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

_{Like Discuss Correct / Improve java bytecode jvm compiler portable features of java basic interview question}

Q99. What is Comparable Interface?

Core Java

Ans. It is used to sort collections and arrays of objects using the collections.sort() and java.utils. The objects of the class implementing the Comparable interface can be ordered.

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

_{Like Discuss Correct / Improve java collections comparable interface Asked in 7 Companies intermediate frequent}

Try 1 Question(s) Test

Q100. Define Network Programming?

Ans. It refers to writing programs that execute across multiple devices (computers), in which the devices are all connected to each other using a network.

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

_{Like Discuss Correct / Improve java network programming distributed computing architecture}

Search Interview Questions

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