10+ Software Engineer and Java Developer Interview Questions and Answers

Reverse the words in a string of a specific length.

• Split the input string into words

• Iterate through the words and reverse the ones with a length equal to the specified length

• Join the reversed words back into a single string

Write a Java program to print unique elements from two given arrays.

• Create a HashSet to store unique elements from both arrays.

• Iterate through each element in both arrays and add them to the HashSet.

• Convert the HashSet back to an array and print the unique elements.

Microservice architecture is a design approach where an application is composed of small, independent services that communicate over well-defined APIs.

• Microservices communicate with each other through APIs, typically using HTTP/REST or messaging protocols like RabbitMQ or Kafka.

• Service discovery mechanisms like Eureka or Consul can be used to locate and connect to other microservices.

• API gateways can be used to manage and secure communication between microservices.

• Microservic...read more

Java 8 introduced new features like lambda expressions and streams. HashMap in Java 8 has improvements like tree bins for better performance.

• Java 8 features include lambda expressions, streams, default methods in interfaces, etc.

• Internal working of HashMap involves using buckets and linked lists or trees for collision resolution.

• In Java 8, HashMap introduced tree bins to handle situations where a bucket has too many elements, improving performance.

• Enhancements in Java 8 HashM...read more

Used Java 8 features like lambda expressions, streams, and optional in my project.

• Utilized lambda expressions to write concise and readable code.

• Made use of streams for processing collections in a functional style.

• Implemented optional to handle potentially null values more effectively.

OOPs is a programming paradigm based on the concept of objects. Multithreading is the ability of a CPU to execute multiple threads concurrently.

• OOPs stands for Object-Oriented Programming.

• It is based on the concept of objects, which have properties and methods.

• Encapsulation, inheritance, and polymorphism are the main concepts of OOPs.

• Multithreading is the ability of a CPU to execute multiple threads concurrently.

• It allows for parallel execution of multiple tasks.

• Java provides...read more

RestFulAPI's are a type of web service that follows the principles of REST architecture.

• RestFulAPI's use standard HTTP methods like GET, POST, PUT, DELETE for communication.

• They are stateless, meaning each request from a client must contain all the information needed to fulfill the request.

• They typically return data in JSON or XML format.

• RestFulAPI's are designed to be easily scalable and maintainable.

• Example: Twitter API, Google Maps API.

Local, final, and static are types of variables in Java. Exception handling is a way to handle errors in code.

• Local variables are declared within a method and have limited scope.

• Final variables cannot be changed once assigned a value.

• Static variables belong to the class and are shared by all instances of the class.

• Exception handling is a way to handle errors in code and prevent program crashes.

• Try-catch blocks are used to catch and handle exceptions.

• Throw keyword is used to t...read more

Recursion is a process in which a method calls itself continuously until a base condition is met.

• Recursion is used to solve problems that can be broken down into smaller sub-problems.

• It involves a base case and a recursive case.

• Examples include factorial, Fibonacci series, and binary search.

• Recursion can lead to stack overflow errors if not implemented properly.

Exception is an event that occurs during the execution of a program and disrupts the normal flow of instructions.

• Exceptions are used to handle errors and other exceptional events in Java programming.

• They are objects that are thrown at runtime and can be caught and handled by the program.

• Examples of exceptions include NullPointerException, ArrayIndexOutOfBoundsException, and IOException.

Inheritance is a concept in OOP where a class inherits properties and behaviors from another class.

• Child class inherits attributes and methods from a parent class

• Allows for code reusability and promotes the concept of 'is-a' relationship

• Example: Class Animal can be a parent class with attributes like name and methods like eat. Class Dog can inherit from Animal and have additional methods like bark

HashMap is a data structure that stores key-value pairs and uses hashing to efficiently retrieve values.

• HashMap uses hashing to store and retrieve key-value pairs.

• It uses an array of linked lists to handle collisions.

• The internal working involves calculating the hash code of keys to determine the index in the array.

POST is used to create a new resource, PUT is used to update an existing resource, and PATCH is used to partially update an existing resource.

• POST is used to create a new resource on the server.

• PUT is used to update an existing resource on the server. It replaces the entire resource with the new one.

• PATCH is used to partially update an existing resource on the server. It only updates the specified fields.

REST API principles are a set of guidelines for designing APIs that adhere to the principles of REST.

• Use HTTP methods (GET, POST, PUT, DELETE) to perform CRUD operations

• Use resource URIs to represent entities

• Statelessness - each request from a client must contain all the information necessary to process the request

• Use hypermedia links to allow clients to navigate the API dynamically

I am open to working in any location that offers challenging opportunities and a good work-life balance.

• Open to relocation for the right opportunity

• Prefer locations with a strong tech industry presence

• Consider factors like cost of living and quality of life