UST Software Engineer Interview Questions and Answers

To create a custom serializable interface, you need to define an interface with the Serializable marker interface and implement the necessary methods.

• Define an interface with the Serializable marker interface

• Implement the necessary methods for serialization and deserialization

• Ensure all fields in the class implementing the interface are serializable

Criteria in Hibernate is used to create and execute dynamic queries.

• Criteria is an interface in Hibernate that allows the creation of dynamic queries without using HQL or SQL.

• Criteria queries are type-safe and can be easily modified at runtime.

• Criteria queries can be used to fetch entities based on certain conditions or restrictions.

• Example: Criteria criteria = session.createCriteria(Employee.class);

Node.js is a JavaScript runtime built on Chrome's V8 engine, enabling server-side scripting and building scalable network applications.

• Asynchronous and event-driven, making it efficient for I/O operations.

• Uses JavaScript, allowing developers to use the same language for both client and server-side code.

• Rich ecosystem with npm (Node Package Manager) for easy package management.

• Ideal for building real-time applicati...read more

Event loop in JavaScript is a mechanism that allows asynchronous non-blocking behavior by handling events and callbacks.

• Event loop is responsible for handling asynchronous operations in JavaScript.

• It allows JavaScript to perform non-blocking operations by queuing tasks in a loop.

• Event loop continuously checks the call stack and the task queue, moving tasks from the queue to the stack when the stack is empty.

• Exampl...read more

Program to reverse a string using array of characters

• Create an array of characters to store the input string

• Iterate through the input string and store each character in the array

• Iterate through the array in reverse order to construct the reversed string

Calculate total amount of rainwater that can be trapped between bars in an elevation map.

• Iterate through the array to find the maximum height on the left and right of each bar.

• Calculate the amount of water that can be trapped above each bar by taking the minimum of the maximum heights on the left and right.

• Sum up the trapped water above each bar to get the total trapped water for the entire elevation map.