10+ Excelra Knowledge Solutions Interview Questions and Answers

Java 8 Date and Time API provides improved date and time handling capabilities.

• Introduction of new classes like LocalDate, LocalTime, LocalDateTime, ZonedDateTime, OffsetTime, OffsetDateTime, and Instant for better date and time manipulation

• Support for time zones and offsets

• Ability to perform date and time calculations easily

• Enhanced formatting and parsing capabilities

• Integration with existing date and time classes like java.util.Date and java.util.Calendar

A movie booking app system design involves user authentication, movie selection, seat reservation, payment processing, and booking confirmation.

• User authentication: Implement login/signup functionality for users.

• Movie selection: Display list of movies with details like showtimes, ratings, and genres.

• Seat reservation: Allow users to select seats for chosen movie showtime.

• Payment processing: Integrate payment gateway for secure transactions.

• Booking confirmation: Send confirmati...read more

Use SQL query with ORDER BY and LIMIT to find 2nd largest salary.

• Use ORDER BY clause to sort salaries in descending order

• Use LIMIT 1,1 to get the second row after skipping the first row

The pretty function in JavaScript is used to format and display data in a more visually appealing way.

• Pretty function is used to format JSON data for better readability.

• It can be used to display data in a structured and organized manner.

• Pretty function is commonly used in debugging to make output easier to read.

Collections in programming languages are data structures that store and organize multiple elements.

• Collections can be implemented using various data structures such as arrays, linked lists, hash tables, and trees.

• They provide methods for adding, removing, and accessing elements efficiently.

• Examples of collections in Java include ArrayList, LinkedList, HashMap, and TreeSet.

Sorting an array of strings using a sorting algorithm like quicksort or mergesort.

• Use a sorting algorithm like quicksort or mergesort to sort the array of strings.

• Ensure the sorting algorithm is efficient and has a time complexity of O(n log n).

• Consider the space complexity of the sorting algorithm as well.

SOLID principles are a set of five design principles that help make software designs more understandable, flexible, and maintainable.

• S - Single Responsibility Principle: A class should have only one reason to change.

• O - Open/Closed Principle: Software entities should be open for extension but closed for modification.

• L - Liskov Substitution Principle: Objects of a superclass should be replaceable with objects of its subclasses without affecting the functionality.

• I - Interface ...read more

Multi threading is a programming concept where multiple threads within a process execute concurrently, allowing for better performance and responsiveness.

• Allows for parallel execution of tasks within a single process

• Improves performance by utilizing multiple CPU cores

• Can lead to synchronization issues if not handled properly

• Examples include web servers handling multiple client requests simultaneously

Reviewing Java classes for code quality and best practices

• Check for proper naming conventions and readability of code

• Ensure that the code follows SOLID principles and design patterns

• Look for potential bugs, performance issues, and security vulnerabilities

• Verify that the code is well-documented and includes appropriate comments

• Evaluate the test coverage and quality of unit tests