Trainee Programmer Interview Questions and Answers for Freshers

Polymorphism is the ability of an object to take on many forms.

• Polymorphism allows objects of different classes to be treated as objects of a common superclass.

• It enables methods to be defined in the superclass and overridden in the subclasses.

• Polymorphism helps in achieving code reusability and flexibility in object-oriented programming.

• Example: A superclass 'Animal' with subclasses 'Dog' and 'Cat'. Both 'Dog' and 'Cat' can be treated as 'Animal'.

I rate myself differently in different languages based on my experience and proficiency.

• Java - 8: I have worked on multiple projects using Java and have a good understanding of its concepts.

• Python - 7: I have used Python for scripting and automation tasks and have a decent understanding of its libraries.

• C++ - 6: I have basic knowledge of C++ and have implemented some algorithms using it.

• JavaScript - 8: I have worked on web development projects using JavaScript and its framewo...read more

A program to check if a given string is a palindrome or not.

• Take input string from user

• Reverse the string

• Compare the reversed string with the original string

• If both are same, then the string is a palindrome

• Else, the string is not a palindrome

API stands for Application Programming Interface. It is a set of protocols, routines, and tools for building software applications.

• API allows different software applications to communicate with each other

• It defines how software components should interact

• APIs can be public or private

• Examples of APIs include Google Maps API, Twitter API, and Facebook API

A pointer is a variable that stores the memory address of another variable. Inheritance is a mechanism in object-oriented programming where a new class inherits properties and behaviors from an existing class.

• Pointer is used to store memory address of a variable

• Pointer can be dereferenced to access the value stored at that memory address

• Example: int *ptr; ptr = # *ptr = 10; // num now has value 10

• Inheritance allows a new class to inherit properties and behaviors from an exist...read more

Creating a table in a DBMS

• Use CREATE TABLE statement

• Specify table name and column names with data types

• Add constraints like primary key, foreign key, etc.

• Example: CREATE TABLE employees (id INT PRIMARY KEY, name VARCHAR(50), age INT)

• Execute the statement to create the table

Java is a fully object-oriented programming language.

• Java supports all four pillars of OOP: encapsulation, inheritance, polymorphism, and abstraction.

• Classes and objects are fundamental concepts in Java.

• Java allows for the creation of user-defined classes and objects.

• Inheritance enables code reusability in Java.

• Polymorphism allows objects to be treated as instances of their parent class.

• Abstraction allows for hiding implementation details and showing only necessary features t...read more