ComFuture Solutions Interview Questions and Answers

You can create an object of a class with a private constructor by using a static method within the class.

• Create a static method within the class that returns an instance of the class.

• Call the static method to create an object of the class.

SQL query to fetch first 10 rows from the table

• Use SELECT statement

• Add LIMIT clause with 10 as argument

• Optionally, use ORDER BY clause for specific order

Yes, we can make a constructor private in Java.

• Private constructors are used to prevent instantiation of a class from outside the class itself.

• Private constructors are commonly used in singleton design pattern.

• Private constructors can be used in utility classes where all methods are static and no instance creation is needed.

Non-aggregate functions in SQL are used to manipulate individual data values.

• Non-aggregate functions operate on individual data values, rather than groups of values.

• Examples include string functions (e.g. CONCAT, SUBSTRING), date functions (e.g. DATEADD, DATEDIFF), and mathematical functions (e.g. ABS, ROUND).

• These functions can be used in SELECT, WHERE, and ORDER BY clauses to manipulate data.

• Non-aggregate functions can also be used in conjunction with aggregate functions to...read more

Securing an API involves using authentication, authorization, encryption, and input validation.

• Use authentication methods like OAuth, JWT, or API keys to verify the identity of clients accessing the API.

• Implement authorization to control what actions different users can perform within the API.

• Encrypt data transmission using HTTPS to protect sensitive information from being intercepted.

• Validate and sanitize input data to prevent common security vulnerabilities like SQL injecti...read more