American Express Full Stack Developer Interview Questions, Process, and Tips

Round duration - 60 Minutes
Round difficulty - Medium

This round had questions mainly from Java 8 and its important features followed by some questions from Spring Boot.

Q1. What are Java 8 streams?
Ans. 
Java 8 streams are a sequence of elements that can be processed in parallel or sequentially.
• Streams provide a functional programming approach to process collections in Java.

• They allow for concise and expressive code.

• Streams can be used to filter, map, reduce, and perform other operations on data.

• Example: List numbers = Arrays.asList(1, 2, 3, 4, 5); numbers.stream().filter(n -> n % 2 == 0).forEach(System.out::println);

• T...read more
Answered by AI
Add your answer
Q2. Write a Java 8 program to iterate through a Stream using the forEach method.
Ans. 
A Java 8 program to iterate a Stream using the forEach method.
• Create a Stream object from a collection or array

• Use the forEach method to perform an action on each element of the Stream

• The action can be a lambda expression or a method reference
Answered by AI
Add your answer
Q3. How does Spring Boot work?
Ans. 
Spring Boot is a framework that simplifies the development of Java applications by providing default configurations and dependencies.
• Spring Boot eliminates the need for manual configuration by providing sensible defaults.

• It uses an embedded server, such as Tomcat or Jetty, to run the application.

• Spring Boot automatically configures the application based on the dependencies added to the project.

• It promotes convention ov...read more
Answered by AI
Add your answer
Q4. What is dependency injection?
Ans. 
Dependency Injection is a design pattern where the dependencies of a class are provided externally rather than being created within the class itself.
• Dependency Injection helps in achieving loose coupling between classes.

• It allows for easier testing and maintenance of code.

• In Spring Boot, dependencies are injected using annotations like @Autowired.

• Example: In a Spring Boot application, if a class requires a database con...read more
Answered by AI
Add your answer
Q5. Can you explain the @RestController annotation in Spring Boot?
Ans. 
The @RestController annotation in Spring Boot is used to mark a class as a RESTful controller.
• It combines the @Controller and @ResponseBody annotations.

• It eliminates the need for annotating each method with @ResponseBody.

• It automatically serializes the return value of the methods into JSON/XML response.

• It is commonly used to build RESTful web services in Spring Boot.
Answered by AI
Add your answer
Q6. What are the different methods of session management in Servlets?
Ans. 
Different methods of session management in Servlet
• Cookies

• URL Rewriting

• Hidden Form Fields

• Session Tracking API

• HTTP Session
Answered by AI
Add your answer

Round duration - 60 Minutes
Round difficulty - Medium

This was a preety much mixed round ranging questions from Java , MVC to DBMS , Web Security and API Design. More emphasis was given on the fundamentals of the subject rather than the advanced topics.

Q1. What is CORS in MVC and how does it work?
Ans. 
CORS in MVC is Cross-Origin Resource Sharing, a mechanism that allows restricted resources on a web page to be requested from another domain.
• CORS is a security feature implemented in web browsers to prevent cross-origin requests by default.

• It works by adding specific HTTP headers to the server's response, indicating which origins are allowed to access the resources.

• In MVC, CORS can be configured using the 'EnableCors' ...read more
Answered by AI
Add your answer
Q2. Can you explain in brief the role of different MVC components?
Ans. 
MVC components include Model, View, and Controller. Model represents data and business logic, View displays the data, and Controller handles user input and updates the Model and View.
• Model: Represents data and business logic

• View: Displays the data to the user

• Controller: Handles user input and updates the Model and View
Answered by AI
Add your answer
Q3. What is the difference between a clustered index and a non-clustered index?
Ans. 
Clustered index determines the physical order of data in a table, while non-clustered index has a separate structure.
• Clustered index determines the physical order of data in a table

• Non-clustered index has a separate structure that includes a copy of the indexed columns and a pointer to the actual data

• A table can have only one clustered index, but multiple non-clustered indexes

• Clustered index is faster for retrieving la...read more
Answered by AI
Add your answer
Q4. What is SQL injection?
Ans. 
SQL injection is a web security vulnerability that allows an attacker to manipulate a database query to execute unauthorized actions.
• SQL injection occurs when user-supplied data is not properly validated or sanitized before being used in an SQL query.

• Attackers can exploit this vulnerability to bypass authentication, retrieve sensitive data, modify or delete data, or even execute arbitrary commands.

• To prevent SQL inject...read more
Answered by AI
Add your answer
Q5. What are the advantages of web services?
Ans. 
Web services offer advantages such as interoperability, scalability, reusability, and platform independence.
• Interoperability: Web services allow different applications to communicate and share data regardless of the programming languages or platforms they are built on.

• Scalability: Web services can handle a large number of requests and can be easily scaled up or down to meet changing demands.

• Reusability: Web services pr...read more
Answered by AI
Add your answer

Round duration - 45 Minutes
Round difficulty - Medium

This round started with some questions from Frontend Web Development primarily from HTML and CSS followed by some questions from DevOps and Git. The interviewer was quite satisfied by my answers and overall this round went preety well.

Q1. How can you optimize the loading of website assets?
Ans. 
Optimize website assets loading by minimizing file sizes, leveraging caching, and using asynchronous loading.
• Minimize file sizes by compressing images, minifying CSS and JavaScript files

• Leverage caching by setting appropriate cache headers and using a content delivery network (CDN)

• Use asynchronous loading techniques such as lazy loading, deferred loading, and async/defer attributes

• Combine and bundle multiple files to r...read more
Answered by AI
Add your answer
Q2. What are the new tags for media elements introduced in HTML5?
Ans. 
The new tags in Media Elements in HTML5 are
• The

• The

• Both tags support various attributes and can be styled using CSS.

• Example:

• Example:
Answered by AI
Add your answer
Q3. Can you explain a use case for Docker?
Ans. 
Docker is a containerization platform that allows developers to package applications with their dependencies for easy deployment and scalability.
• Docker enables developers to create lightweight, isolated containers that can run on any operating system.

• It simplifies the deployment process by ensuring that the application and its dependencies are bundled together, eliminating compatibility issues.

• Docker allows for easy sc...read more
Answered by AI
Add your answer
Q4. What is the difference between 'git pull' and 'git fetch'?
Ans. 
Git pull combines git fetch and git merge, while git fetch only downloads new data from a remote repository.
• Git pull is used to update the local branch with the latest changes from the remote repository.

• Git fetch only downloads new data from the remote repository, but does not integrate it into the local branch.

• Git pull is a combination of git fetch and git merge commands.

• Git fetch is useful to see what changes have be...read more
Answered by AI
Add your answer

Easy Questions based on Array and String Data Structure

Q1. How does a website URL works
Ans. 
A website URL is a unique address that identifies a web page on the internet.
• URL stands for Uniform Resource Locator

• It consists of a protocol (http/https), domain name, and path

• The domain name is translated to an IP address using DNS

• The path specifies the location of the resource on the server

• Example: https://www.google.com/search?q=url
Answered by AI
Add your answer
Q2. Event loop in Javascript
Ans. 
Event loop is a mechanism in JavaScript that handles asynchronous operations.
• Event loop continuously checks the call stack and the task queue.

• If the call stack is empty, it takes the first task from the queue and pushes it to the call stack.

• Callbacks are added to the task queue when an asynchronous operation is completed.

• Event loop ensures that the code runs in a non-blocking way.

• Example: setTimeout() function adds a c...read more
Answered by AI
Add your answer
Q3. Simple Coding based, Given an array, find a pair with sum = k.
Ans. 
Given an array, find a pair with sum = k.
• Use a hash table to store the difference between k and each element in the array.

• Iterate through the array and check if the current element is present in the hash table.

• If it is present, return the pair of elements that add up to k.
Answered by AI
Add your answer

Q1. Java Exceptions, Streams
Add your answer
Q2. Find first minimum and maximum number in an array using streams
Ans. 
Find first minimum and maximum number in an array using streams
• Use IntStream to convert array to stream of integers

• Use min() and max() methods to find minimum and maximum values

• Use findFirst() method to get the first occurrence of minimum and maximum values
Answered by AI
Add your answer

DP graphs strings it was good

Q1. Reverse a linkded list
Ans. 
Reverse a linked list by changing the direction of pointers
• Start with three pointers: current, previous, and next

• Iterate through the list, updating pointers to reverse the direction

• Return the new head of the reversed list
Answered by AI
Add your answer
Q2. Print fibonacci series
Ans. 
The Fibonacci series is a sequence of numbers where each number is the sum of the two preceding ones.
• Start with two variables initialized to 0 and 1

• Loop through desired number of iterations, adding the previous two numbers to get the next number

• Print or store each number in the series
Answered by AI
Add your answer

Q1. Why do you want to switch
Ans. 
I want to switch to explore new technologies and challenges in a different industry.
• Interested in learning new skills and technologies

• Seeking new challenges and opportunities for growth

• Want to explore different industry perspectives
Answered by AI
Add your answer
Q2. Salry expectations
Add your answer

Q1. Question on oop concepts
Add your answer
Q2. Coding questions
Add your answer

It was just a typical logical reasoning and aptitude MCQ test

There were 2 coding questions and you can select any language for solving it. The test was online

Q1. He simply asked me which coding language I prefer and why ? (Mine was C++)
Add your answer
Q2. Difference between C and C++?
Ans. 
C is a procedural programming language while C++ is an object-oriented programming language.
• C is a procedural programming language, while C++ supports both procedural and object-oriented programming.

• C does not have classes and objects, while C++ does.

• C does not support function overloading, while C++ does.

• C does not have exception handling, while C++ does.

• C does not have namespaces, while C++ does.
Answered by AI
View 1 more answer
Q3. What is Object oriented programming?
Ans. 
Object oriented programming is a programming paradigm based on the concept of objects, which can contain data and code.
• Objects are instances of classes, which define the structure and behavior of the objects.

• Encapsulation, inheritance, and polymorphism are key principles of object oriented programming.

• Example: Inheritance allows a class to inherit properties and methods from another class.

• Example: Encapsulation hides t...read more
Answered by AI
View 1 more answer
Q4. What are the 4 pillars of OOPs?
Ans. 
Encapsulation, Inheritance, Polymorphism, Abstraction
• Encapsulation: Bundling data and methods that operate on the data into a single unit

• Inheritance: Ability of a class to inherit properties and behavior from another class

• Polymorphism: Ability to present the same interface for different data types

• Abstraction: Hiding the complex implementation details and showing only the necessary features
Answered by AI
Add your answer
Q5. Write down code implementing all 4 pillars of OOPs.
Ans. 
Code implementing all 4 pillars of OOPs
• Encapsulation: Encapsulate data within classes and provide public methods to access and modify the data.

• Inheritance: Create a hierarchy of classes where child classes inherit attributes and methods from parent classes.

• Polymorphism: Allow objects of different classes to be treated as objects of a common superclass through method overriding and overloading.

• Abstraction: Hide complex ...read more
Answered by AI
Add your answer
Q6. Difference between Stacks and Queues?
Ans. 
Stacks are Last In First Out (LIFO) data structures, while Queues are First In First Out (FIFO) data structures.
• Stacks: Elements are added and removed from the same end, like a stack of plates. Example: Undo feature in text editors.

• Queues: Elements are added at the rear and removed from the front, like a line of people waiting. Example: Print queue in a printer.
Answered by AI
Add your answer
Q7. Write a code to find the 2nd largest element in an array.
Ans. 
Code to find the 2nd largest element in an array
• Sort the array in descending order and return the element at index 1

• Iterate through the array and keep track of the two largest elements

• Handle edge cases like arrays with less than 2 elements
Answered by AI
Add your answer
Q8. What is merge sort and its Algorithm ?
Ans. 
Merge sort is a divide and conquer algorithm that divides the input array into two halves, sorts them recursively, and then merges them.
• Divide the input array into two halves

• Recursively sort each half

• Merge the sorted halves back together
Answered by AI
Add your answer
Q9. What is DBMS and RDBMS and difference between them?
Ans. 
DBMS stands for Database Management System, while RDBMS stands for Relational Database Management System. RDBMS is a type of DBMS.
• DBMS is a software system that allows users to define, create, maintain and control access to the database.

• RDBMS is a type of DBMS that stores data in a structured format using tables with rows and columns.

• RDBMS enforces a set of rules called ACID properties to ensure data integrity, while D...read more
Answered by AI
Add your answer
Q10. What is SQL and who its different from mySQL?
Ans. 
SQL is a standard language for managing databases, while MySQL is a specific open-source relational database management system.
• SQL stands for Structured Query Language and is used to communicate with databases.

• SQL is a standard language that can be used with various database management systems.

• MySQL is a specific open-source relational database management system that uses SQL.

• MySQL is one of the most popular database m...read more
Answered by AI
Add your answer
Q11. Difference between Delete, Truncate and Drop?
Ans. 
Delete removes specific rows from a table, Truncate removes all rows from a table, and Drop removes the table itself.
• Delete is a DML command that removes specific rows from a table based on a condition.

• Truncate is a DDL command that removes all rows from a table but keeps the table structure.

• Drop is a DDL command that removes the entire table along with its structure.
Answered by AI
View 1 more answer
Q12. Different kind of Joins in DBMS ?
Ans. 
Different types of joins in DBMS include inner join, outer join, left join, right join, and full join.
• Inner join: Returns rows when there is a match in both tables.

• Outer join: Returns all rows from one table and only matching rows from the other table.

• Left join: Returns all rows from the left table and the matched rows from the right table.

• Right join: Returns all rows from the right table and the matched rows from the ...read more
Answered by AI
Add your answer
Q13. And at last 2 to 3 SQL queries. They were not that hard, Just basic queries.
Add your answer

Logical,quants,coding

Q1. Java,sql,testing,sdlc
Add your answer
Q2. What is method overriding?
Ans. 
Method overriding is a feature in object-oriented programming where a subclass provides a specific implementation of a method that is already provided by its parent class.
• In method overriding, the method in the subclass has the same name, return type, and parameters as the method in the parent class.

• The purpose of method overriding is to provide a specific implementation of a method in the subclass that is different fr...read more
Answered by AI
Add your answer
Q3. What is exception handling in java?
Ans. 
Exception handling in Java is a mechanism to handle runtime errors and prevent program crashes.
• Exceptions are objects that represent errors or unexpected events during program execution.

• Java provides try, catch, and finally blocks to handle exceptions.

• try block contains the code that may throw an exception, catch block handles the exception, and finally block is executed regardless of an exception.

• Example: try { // cod...read more
Answered by AI
Add your answer

Q1. Normal questions
Add your answer
Q2. Why you want to join our company?
Add your answer