3500+ Senior Software Engineer Interview Questions and Answers

Exception handling is a mechanism in programming to handle and manage errors or exceptional situations that may occur during program execution.

• Exception handling is used to catch and handle errors or exceptions in a program.

• It allows the program to gracefully handle errors and prevent abrupt termination.

• Exception handling involves the use of try-catch blocks to catch and handle exceptions.

• The catch block contains code to handle the exception, such as displaying an error messa...read more

Concurrent hashmap allows multiple threads to access and modify the map concurrently without causing data inconsistency.

• Concurrent hashmap is thread-safe and allows multiple threads to access and modify the map concurrently.

• It uses a technique called lock striping to divide the map into segments and apply locks to each segment instead of the entire map.

• This allows multiple threads to access different segments of the map concurrently without causing data inconsistency.

• Concurre...read more

Array is a fixed-size data structure while ArrayList is a dynamic-size data structure in Java.

• Array has a fixed length, while ArrayList can dynamically resize.

• Array can store both primitive and object types, while ArrayList can only store object types.

• Array uses square brackets [] for declaration, while ArrayList uses angle brackets <>.

• Array is more memory efficient than ArrayList.

• Array provides direct access to elements using index, while ArrayList requires methods like get(...read more

Declare expression is used to define reusable expressions. Sub report is a report within a report.

• Declare expression helps in reducing redundancy and improving maintainability of the code.

• It allows defining expressions that can be used across multiple rules and decision tables.

• For example, a declare expression can be used to calculate the age of a customer based on their date of birth.

• A sub report is a report that is embedded within another report.

• It is used to display relate...read more

Find the maximum profit from buying and selling a stock given an array of its values.

• Iterate through the array and keep track of the minimum value seen so far.

• Calculate the profit at each index and update the maximum profit seen.

• Return the maximum profit.

ACID properties are a set of properties that guarantee reliability and consistency in database transactions.

• ACID stands for Atomicity, Consistency, Isolation, and Durability.

• Atomicity ensures that a transaction is treated as a single unit of work, either all of its operations are executed or none.

• Consistency ensures that a transaction brings the database from one valid state to another.

• Isolation ensures that concurrent transactions do not interfere with each other.

• Durability ...read more

Yes

• I have extensive experience dealing with customers through email

• I prioritize clear and concise communication to address customer inquiries and concerns

• I ensure prompt responses and follow-ups to maintain customer satisfaction

• I have successfully resolved complex issues and provided technical guidance via email

• I maintain a professional and empathetic tone in all customer interactions

Yes, I have experience working with semantic tags in HTML.

• Used semantic tags like <header>, <nav>, <main>, <section>, <article>, <aside>, <footer> for better structure and SEO.

• Understand the importance of using semantic tags for accessibility and search engine optimization.

• Semantic tags help in organizing content and making it more readable for developers and browsers.

Yes, I have utilized CSS preprocessors such as SASS and LESS.

• I have experience using SASS to streamline my CSS workflow by utilizing variables, mixins, and nesting.

• I have also worked with LESS to improve code organization and maintainability through features like variables and functions.

Block scope and function scope are two types of scopes in JavaScript that determine the visibility and accessibility of variables.

• Block scope refers to the visibility of variables within a block of code enclosed by curly braces. Variables declared with 'let' and 'const' have block scope.

• Function scope refers to the visibility of variables within a function. Variables declared with 'var' have function scope.

• Variables declared with 'let' and 'const' are only accessible within t...read more

Various state management techniques in React include Context API, Redux, and local state.

• Context API: React's built-in solution for passing data through the component tree without having to pass props down manually at every level.

• Redux: A popular state management library for React applications, allowing for a centralized store to manage application state.

• Local state: Managing state within individual components using useState hook or this.state in class components.

useMemo is used to memoize a value, while useCallback is used to memoize a function.

• useMemo is used to memoize a value and recompute it only when its dependencies change.

• useCallback is used to memoize a callback function and prevent unnecessary re-renders.

• Example: useMemo can be used to memoize the result of a complex computation, while useCallback can be used to memoize an event handler function.

Using Java Stream to find the second highest number, Java 8 changes, HashMap and HashSet internal implementation.

• Use Java Stream to sort the numbers in descending order and skip the first element to get the second highest number.

• Java 8 introduced lambda expressions, functional interfaces, Stream API, default methods in interfaces, and new Date and Time API.

• HashMap uses buckets to store key-value pairs, while HashSet uses HashMap internally to store unique elements.

• HashMap all...read more

Singleton Design Pattern ensures only one instance of a class exists. No, we cannot create a clone of an object from singleton class.

• Singleton pattern restricts the instantiation of a class to one object.

• It is used when only one object is required to coordinate actions across the system.

• The instance is created only when it is requested for the first time.

• The constructor of the singleton class is private.

• Clone method is not supported in singleton pattern.

LOD, Pie Chart, Dual Axis Chart in Tableau

• LOD (Level of Detail) is used to compute aggregations that are not at the level of detail of the visualization

• Pie Chart is used to show the proportion of different categories in a dataset

• Dual Axis Chart is used to compare two measures with different scales on the same chart

• To create LOD, use curly braces and specify the level of detail

• To create Pie Chart, drag the dimension to the Columns/Rows shelf and the measure to the Marks card

• To...read more

Code to find frequency of characters in a given string

• Use a hash table to store character frequencies

• Iterate through the string and update the hash table accordingly

• Print the hash table to display the character frequencies

One design pattern I know is the Singleton pattern, which ensures a class has only one instance and provides a global point of access to it.

• Singleton pattern can be implemented in scenarios where only one instance of a class is needed, such as a logger class or a configuration class.

• It is commonly used in database connections, thread pools, and caching mechanisms.

• Example: Implementing a Singleton pattern for a database connection class to ensure only one connection is establi...read more

Distributed systems are a network of independent computers that work together to achieve a common goal. Security can be maintained through encryption, authentication, access control, and monitoring.

• Distributed systems consist of multiple computers that communicate and coordinate actions to achieve a common goal.

• Security in distributed systems can be maintained through encryption of data in transit and at rest.

• Authentication mechanisms such as passwords, tokens, or biometrics ...read more

Generator functions and symbols in JavaScript. Implementation of const keyword in ES5.

• Generator functions are functions that can be paused and resumed, allowing for lazy evaluation of data.

• Symbols are a new primitive type in ES6 that can be used as unique identifiers.

• To implement const in ES5, we can use Object.defineProperty to create a read-only property on an object.

Yes, I have worked on Kafka. My code had 10 partitions.

• Yes, I have experience working with Kafka and have implemented code with multiple partitions.

• In one of my projects, I used Kafka with 10 partitions to distribute the workload efficiently.

• Having multiple partitions in Kafka helped in achieving high throughput and scalability for real-time data processing.

Java 8 introduced several new features including lambda expressions, functional interfaces, streams, and default methods.

• Lambda expressions: Enable functional programming in Java by expressing instances of single-method interfaces (functional interfaces) concisely.

• Functional interfaces: Interfaces with a single abstract method, such as java.util.function.Function or java.util.function.Predicate.

• Streams: Allow for processing sequences of elements in a functional style, support...read more

Interfaces define contracts for behavior while abstract classes provide partial implementation.

• Interfaces cannot have implementation while abstract classes can have partial implementation.

• A class can implement multiple interfaces but can inherit from only one abstract class.

• Interfaces are used for loose coupling while abstract classes are used for code reuse.

• Example: An interface 'Drawable' can define a method 'draw' which any class implementing it must define. An abstract cl...read more

I have implemented RE framework in 3 projects.

• Implemented RE framework in 3 projects

• Used RE framework for automating end-to-end processes

• Leveraged RE framework's modular structure for easy maintenance

• Examples: Invoice processing, Order management, HR onboarding

An unique id for a massive parallel system can be generated using a combination of timestamp, machine id and a random number.

• Use a timestamp to ensure uniqueness

• Include a machine id to avoid collisions in a distributed system

• Add a random number to further increase uniqueness

• Consider using a UUID (Universally Unique Identifier) for simplicity

• Ensure the id generation algorithm is thread-safe

Thread Scheduler is responsible for managing the execution of multiple threads in a multitasking environment.

• Thread Scheduler determines the order in which threads are executed.

• It allocates CPU time to each thread based on priority and scheduling algorithm.

• Time Slicing is a technique used by Thread Scheduler to allocate a fixed time slice to each thread before switching to another.

• It ensures fair execution of threads and prevents a single thread from monopolizing the CPU.

• Exam...read more

package.json is a file that contains metadata about a project and its dependencies.

• package.json is used in Node.js projects to manage dependencies

• Dependencies are packages required for the project to run

• Dev dependencies are packages required for development and testing

• Dependencies and dev dependencies are listed separately in package.json

• Example: "dependencies": {"express": "^4.17.1"}, "devDependencies": {"nodemon": "^2.0.7"}

CTE, Temp table and Table variable are used to store temporary data in SQL Server.

• CTE (Common Table Expression) is a temporary named result set that can be referenced within a SELECT, INSERT, UPDATE, or DELETE statement.

• Temp table is a physical table that is created in the tempdb database and can be used to store temporary data.

• Table variable is a variable that can store a result set for later use and is similar to a temp table but is stored in memory.

• CTE is useful for recurs...read more

Yes, a new column can be added in between 2 existing columns in a table by altering the table structure.

• Yes, a new column can be added in between 2 existing columns by using the ALTER TABLE statement in SQL.

• The new column can be specified to be added after a specific existing column.

• For example, ALTER TABLE table_name ADD new_column_name datatype AFTER existing_column_name;

Interview questions for Senior Software Engineer position

• Array list vs linked list - array list is faster for random access, linked list is better for frequent insertions/deletions

• Getters and setters are used for encapsulation and to control access to class variables

• Loose coupling allows for easier maintenance and testing, tight coupling can lead to code that is difficult to modify

• Spring Boot is a framework for building standalone applications, MVC is a design pattern for sep...read more