Quest Global Senior Java Developer Interview Questions and Answers

Interfaces define a contract for classes to implement certain methods and properties.

• Interfaces allow for polymorphism and loose coupling.

• Classes can implement multiple interfaces.

• Interfaces cannot be instantiated on their own.

• Interfaces can have default method implementations.

• Interfaces can be used to enforce design patterns like the adapter pattern.

Computer networking is the practice of connecting devices together to share resources and communicate with each other.

• Computer networking involves the use of hardware and software to connect devices together, such as computers, printers, and servers.

• Networking protocols, such as TCP/IP, are used to facilitate communication between devices.

• Examples of computer networks include local area networks (LANs), wide area netwo...read more

C++ is an extension of C with object-oriented programming features.

• C++ supports classes and objects while C does not.

• C++ has better support for polymorphism and inheritance.

• C++ has a standard template library (STL) which C does not have.

• C++ allows function overloading while C does not.

• C++ has exception handling while C does not.

For loop is used for iterating over a sequence while while loop is used for iterating until a condition is met.

• For loop is used when the number of iterations is known beforehand

• While loop is used when the number of iterations is not known beforehand

• For loop is faster than while loop for iterating over a sequence

• While loop is useful for iterating until a specific condition is met

• For loop can be used with range() functio...read more

To reverse a string without using any looping and inbuilt functions, we can use recursion.

• Create a function that takes a string as input.

• If the length of the string is 0 or 1, return the string.

• Otherwise, call the function recursively with the substring starting from the second character and concatenate the first character at the end.

• Return the reversed string.

• Example: reverseString('hello') returns 'olleh'.

A priority queue can be implemented using a single queue or multiple queues.

• One approach is to use a single queue and assign priorities to elements using a separate data structure.

• Another approach is to use multiple queues, each representing a different priority level.

• For example, if there are three priority levels, three queues can be used to implement the priority queue.

An array of objects can be used to implement a heterogeneous array.

• Each element in the array can be an object that represents a different data type.

• The objects can have different properties and methods based on their respective data types.

• For example, an element can be an object representing a string with a 'value' property and a 'length' method.

Developed a web-based inventory management system for a retail company.

• Used HTML, CSS, and JavaScript for the front-end development.

• Implemented a RESTful API using Node.js and Express for the back-end.

• Utilized a MySQL database to store and manage inventory data.

• Implemented features like product search, order management, and reporting.

• Ensured data security and user authentication using encryption and JWT.

• Collaborated wi...read more

The missing rupee is not actually missing. The calculation is misleading and does not account for the total amount paid.

• The initial amount paid by each person was Rs.10, totaling Rs.30.

• The owner gave them a discount of Rs.5, so they paid Rs.25 in total.

• The broker took Rs.2, leaving them with Rs.23.

• When the broker returned Rs.1 to each person, they each received Rs.1 back, totaling Rs.3.

• So, the total amount paid by the ...read more

Inheritance in Java allows a class to inherit properties and methods from another class.

• Inheritance is achieved using the 'extends' keyword.

• The class that is being inherited from is called the superclass or parent class.

• The class that inherits from the superclass is called the subclass or child class.

• Subclasses can access the public and protected members of the superclass.

• Inheritance promotes code reusability and allow...read more

A program to check if a given number is a palindrome or not.

• Convert the number to a string.

• Reverse the string and compare it with the original string.

• If they are equal, the number is a palindrome.

• If not, the number is not a palindrome.

Normalisation is the process of organizing data in a database to reduce redundancy and improve data integrity.

• It involves breaking down a table into smaller tables and defining relationships between them.

• Normalization helps to eliminate data inconsistencies and anomalies.

• There are different levels of normalization, with each level having specific rules to follow.

• For example, first normal form (1NF) requires that each t...read more

Yes, I am ready to relocate anywhere in India or outside upon company needs.

• I am open to exploring new locations and cultures.

• I understand that relocation may be necessary for career growth and opportunities.

• I am adaptable and willing to adjust to new environments.

• I have experience working in diverse teams and can easily integrate into new settings.

I would be ready to accept a project in Java even if I was trained in DotNet earlier.

• I have a strong foundation in programming principles and concepts, which can be applied to any language.

• I am confident in my ability to quickly learn and adapt to new technologies.

• I have experience working with multiple programming languages and frameworks.

• I can leverage my knowledge of DotNet to understand similar concepts in Java.

• I a...read more

I want to join Sapient because of its reputation for innovative projects and collaborative work environment.

• Sapient is known for working on cutting-edge projects that push the boundaries of technology

• I value the collaborative work environment at Sapient, where team members support each other to achieve success

• I am impressed by Sapient's commitment to professional development and growth opportunities for employees

My expectations from Sapient

• I expect Sapient to provide a challenging and innovative work environment

• I expect Sapient to offer opportunities for professional growth and learning

• I expect Sapient to have a collaborative and supportive team culture

• I expect Sapient to provide competitive compensation and benefits

• I expect Sapient to have a strong focus on quality and delivering excellent software solutions