Polymorphism Differences in Object-Oriented Databases

Introduction

Polymorphism is a core concept in object-oriented programming that allows methods to do different things based on the object it is acting upon. In the context of object-oriented databases (OODB), understanding the differences in polymorphism is crucial for effective database design and implementation.

Definition of Polymorphism

Polymorphism refers to the ability of different classes to be treated as instances of the same class through a common interface. It primarily allows for two main types:

• Compile-time Polymorphism (Static Binding)
• Run-time Polymorphism (Dynamic Binding)

Types of Polymorphism

1. Compile-time Polymorphism

This type is resolved during compile time and is typically achieved through method overloading or operator overloading.

2. Run-time Polymorphism

This type is resolved during runtime and is achieved through method overriding.

class Shape {
                void draw() {
                    System.out.println("Drawing Shape");
                }
                
                void draw(int radius) {
                    System.out.println("Drawing Circle with radius: " + radius);
                }
            }

class Shape {
                void draw() {
                    System.out.println("Drawing Shape");
                }
            }

            class Circle extends Shape {
                void draw() {
                    System.out.println("Drawing Circle");
                }
            }

            Shape shape = new Circle();
            shape.draw(); // Output: Drawing Circle
            

Implementation in OODB

In Object-Oriented Databases, polymorphism is often achieved using inheritance and interfaces. Here’s a step-by-step process for implementing polymorphism:

1. Create a base class or interface.
2. Define the common methods that subclasses must implement.
3. Implement the subclasses, overriding the common methods as needed.
4. Utilize the base class reference to invoke the overridden methods.

Best Practices

• Use interfaces to define a common contract for polymorphic behavior.
• Keep method signatures consistent across subclasses to avoid confusion.
• Document polymorphic methods clearly for better maintainability.

FAQ