Fidelity Investments Full Stack Engineer Interview Questions and Answers

The Internet is a global network of computers that communicate with each other using standardized protocols.

• The Internet is made up of millions of interconnected devices, including computers, servers, routers, and switches.

• Data is transmitted over the Internet in the form of packets, which are small units of information.

• The Internet uses a set of protocols, such as TCP/IP, to ensure reliable and efficient communication...read more

HTTP is unsecured while HTTPS is secured with SSL/TLS encryption.

• HTTP stands for Hypertext Transfer Protocol, while HTTPS stands for Hypertext Transfer Protocol Secure.

• HTTP operates on port 80, while HTTPS operates on port 443.

• HTTP data is transmitted in plain text, while HTTPS data is encrypted using SSL/TLS.

• HTTPS provides authentication, integrity, and confidentiality of data exchanged between a client and a server.

• W...read more

White box testing is a method of testing where the internal structure and implementation details of the software are known and tested. Black box testing is a method of testing where the internal structure and implementation details of the software are unknown and only the inputs and outputs are tested.

• White box testing is also known as clear box testing, glass box testing, or structural testing.

• It focuses on testing th...read more

Print a pattern using code

• Use nested loops to iterate through rows and columns

• Use string concatenation to build each row of the pattern

• Print each row to display the pattern

Merge two arrays without using a third array.

• Use the concat() method to merge the arrays.

• Alternatively, you can use the push() method to add elements from one array to another.

• Remember to handle the case where the arrays have different lengths.

The probability that three ants at the corner of a triangle will never meet.

• The ants can move randomly in any direction.

• The probability depends on the shape and size of the triangle.

• The probability can be calculated using geometric probability or simulation.

• Assumptions need to be made about the ants' movement patterns.

I have regretted decisions in the past but learned from them to make better choices in the future.

• Regretted not studying enough for a crucial exam, leading to a lower grade. Learned to prioritize studying and time management.

• Regretted not speaking up in a meeting when I had a valuable idea. Learned to be more assertive and confident in sharing my thoughts.

• Regretted not taking a job opportunity that could have advanced ...read more

I come from a close-knit family with a passion for outdoor activities. We recently celebrated my brother's graduation, which was a proud moment for all of us.

• Family: Close-knit and supportive

• Hobbies: Outdoor activities like hiking and camping

• Proud moment: Brother's graduation ceremony

Yes, the string class can be extended in most programming languages.

• Inheritance can be used to extend the functionality of the string class.

• By creating a new class that inherits from the string class, additional methods and properties can be added.

• Extending the string class allows for customization and adding specific functionality to strings.

• Example: In Python, the string class can be extended by creating a new class

Implicit objects in JSP are predefined objects that are available for use without any declaration or initialization.

• Implicit objects in JSP include request, response, session, application, out, config, pageContext, page, exception, and others.

• These objects provide access to various aspects of the JSP environment and can be used to perform common tasks.

• For example, the request object allows access to HTTP request parame...read more

A hash map is a data structure that uses a hash function to map keys to values.

• Hash map stores key-value pairs

• It uses a hash function to compute an index for each key

• Collisions can occur when two keys hash to the same index

• Hash maps provide fast access to values based on their keys

StringBuffer and StringBuilder are both used to manipulate strings, but StringBuffer is thread-safe while StringBuilder is not.

• StringBuffer is synchronized, making it safe for use in multi-threaded environments.

• StringBuilder is not synchronized, making it faster but not thread-safe.

• StringBuffer is preferred when multiple threads are involved, while StringBuilder is preferred for single-threaded scenarios.

• Both classes p...read more

MVC is a software architectural pattern that separates an application into three main components: Model, View, and Controller.

• Model represents the data and business logic of the application.

• View is responsible for displaying the user interface.

• Controller handles user input, updates the model, and interacts with the view.

• MVC promotes separation of concerns and modularity in software development.

• Example: In a web applica...read more

Annotations used in RESTful web services

• 1. @Path - Specifies the URI path for the resource

• 2. @GET - Specifies that the method handles HTTP GET requests

• 3. @POST - Specifies that the method handles HTTP POST requests

• 4. @PUT - Specifies that the method handles HTTP PUT requests

• 5. @DELETE - Specifies that the method handles HTTP DELETE requests

• 6. @PathParam - Binds the value of a URI template parameter to a method paramete...read more

I prefer to work in a location that offers a vibrant and diverse community, with access to cultural events and opportunities for personal growth.

• I value a location that has a strong sense of community and offers a variety of cultural activities.

• Access to educational and personal growth opportunities is important to me.

• I am open to considering different locations that meet these criteria.

I have the analytical skills, experience, and passion to excel in this role.

• I have a strong background in data analysis and interpretation

• I have experience in using various analytical tools and techniques

• I am detail-oriented and have a proven track record of delivering accurate and insightful analysis

• I am a quick learner and can adapt to new challenges and environments easily