Ensono Java Developer Interview Questions and Answers

Oops concepts in Java

• Encapsulation - hiding implementation details

• Inheritance - reusing code and creating parent-child relationships

• Polymorphism - multiple forms of a method or object

• Abstraction - creating abstract classes and interfaces

• Example: Encapsulation - using private variables and public methods

• Example: Inheritance - creating a subclass that inherits from a superclass

• Example: Polymorphism - using method overloa...read more

Altering columns in databases involves modifying the structure of a table by adding, deleting or modifying columns.

• Use ALTER TABLE statement to modify columns

• Add new columns using ADD COLUMN

• Delete columns using DROP COLUMN

• Modify columns using MODIFY COLUMN

• Changing column data type may result in data loss

Reversing a number in Java

• Convert the number to a string

• Use StringBuilder to reverse the string

• Convert the reversed string back to a number

To extract words from a line in Java, split the line using whitespace as delimiter.

• Use the split() method of String class

• Pass the whitespace regex as argument to split() method

• Iterate over the resulting array to get individual words

Generic collections provide type safety and reusability in software development.

• Generic collections allow us to store and manipulate objects of any type in a type-safe manner.

• They provide compile-time type checking, reducing the chances of runtime errors.

• They promote code reusability by allowing the same collection to be used with different types.

• Generic collections improve performance by eliminating the need for boxin...read more

I am a passionate software developer with 5 years of experience in web development and a strong background in computer science.

• 5 years of experience in web development

• Strong background in computer science

• Passionate about software development

To separate personal and professional calls, and to ensure availability and accessibility.

• Separate personal and professional calls

• Ensure availability and accessibility

• Maintain work-life balance

• Avoid mixing personal and work-related contacts

Firmware is a type of software that is embedded in hardware devices to control their functionality.

• Firmware is a combination of hardware and software.

• It is used to control the behavior of hardware devices.

• Firmware is typically stored in non-volatile memory, such as ROM or flash memory.

• Examples of devices that use firmware include routers, printers, and digital cameras.

I am a passionate software developer with experience in building web applications and solving complex problems.

• Experienced in programming languages such as Java, JavaScript, and Python

• Familiar with front-end technologies like HTML, CSS, and React

• Strong problem-solving skills and ability to work in a team environment

• Previous projects include developing a customer management system for a small business