Explain the concept of polymorphism
Theme: Programming Role: Software Engineer Function: Technology
Interview Question for Software Engineer: See sample answers, motivations & red flags for this common interview question. About Software Engineer: Develops and maintains software applications. This role falls within the Technology function of a firm. See other interview questions & further information for this role here
Sample Answer
Example response for question delving into Programming with the key points that need to be covered in an effective response. Customize this to your own experience with concrete examples and evidence
- Definition: Polymorphism is a concept in object-oriented programming that allows objects of different classes to be treated as objects of a common superclass. It enables a single interface to be used for multiple types of objects
- Types of Polymorphism: There are two types of polymorphism: compile-time polymorphism and runtime polymorphism
- Compile-time Polymorphism: Also known as static polymorphism, it is achieved through method overloading and operator overloading. Method overloading allows multiple methods with the same name but different parameters to coexist in a class. Operator overloading enables operators to behave differently based on the operands
- Runtime Polymorphism: Also known as dynamic polymorphism, it is achieved through method overriding. Method overriding allows a subclass to provide a different implementation of a method that is already defined in its superclass. The appropriate method is determined at runtime based on the actual object type
- Benefits of Polymorphism: Polymorphism promotes code reusability, flexibility, and extensibility. It allows for the creation of generic code that can work with objects of different types, reducing code duplication and improving maintainability
- Example: For example, consider a superclass called 'Shape' with subclasses 'Circle' and 'Rectangle'. Both subclasses inherit common properties and methods from the 'Shape' class. Polymorphism allows us to treat a 'Circle' object and a 'Rectangle' object as 'Shape' objects, enabling us to write generic code that can operate on any shape without knowing its specific type
Underlying Motivations
What the Interviewer is trying to find out about you and your experiences through this question
- Technical knowledge: Assessing understanding of polymorphism and its implementation in software engineering
- Problem-solving skills: Evaluating ability to apply polymorphism in solving real-world programming challenges
- Communication skills: Assessing the candidate's ability to explain complex concepts in a clear and concise manner
Potential Minefields
How to avoid some common minefields when answering this question in order to not raise any red flags
- Lack of understanding: Not being able to explain the concept clearly or accurately
- Confusion with other concepts: Mixing up polymorphism with inheritance or method overloading
- Inability to provide examples: Failing to provide real-world examples or use cases of polymorphism
- Limited knowledge: Not being aware of different types of polymorphism like compile-time and runtime polymorphism
- Inability to explain benefits: Not being able to articulate the advantages and benefits of using polymorphism in software development