Basic Java programming for the concept of polymorphism. The video must cover the basic concept and the logic behind polymorphism

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Welcome to Java Polymorphism! Polymorphism is one of the four fundamental principles of Object-Oriented Programming. The word polymorphism comes from Greek, meaning 'many forms'. In Java, polymorphism allows objects of different types to be treated as objects of a common base type, while still maintaining their specific behaviors. Think of it like different shapes - they're all shapes, but each has its own unique properties and methods. Compile-time polymorphism in Java is achieved through method overloading. This means you can have multiple methods with the same name, but they must have different parameter lists. The Java compiler determines which method to call based on the number, type, and order of arguments passed. For example, in our Calculator class, we have three add methods: one for two integers, one for two doubles, and one for three integers. This provides flexibility while keeping the method names intuitive and consistent. Runtime polymorphism is achieved through method overriding and inheritance. When a child class provides a specific implementation of a method that already exists in its parent class, this is called method overriding. The key difference from compile-time polymorphism is that the decision of which method to call is made at runtime, not compile time. In our example, we have an Animal class with a makeSound method, and both Dog and Cat classes override this method with their own implementations. When we create a Dog object but reference it as an Animal, the JVM still calls the Dog's version of makeSound at runtime. Dynamic Method Dispatch is the core mechanism that makes runtime polymorphism possible in Java. When you call a method on an object reference, the Java Virtual Machine doesn't just look at the reference type - it examines the actual object type at runtime. This process involves checking the actual object's class for the method implementation first, and if not found, moving up the inheritance hierarchy until a match is found. This is why when we have an Animal reference pointing to a Dog object, calling makeSound will execute the Dog's version of the method, not the Animal's version. Polymorphism provides numerous benefits that make it essential in object-oriented programming. First, it offers code flexibility by allowing easy extension of existing systems without modifying existing code. Second, it promotes code reusability - you can write generic code that works with multiple types. Third, it improves maintainability by reducing the need to change multiple parts of code when adding new functionality. Fourth, it enables abstraction by hiding implementation details behind common interfaces. Finally, it creates loose coupling between components, making systems more modular and easier to test. In summary, polymorphism embodies the principle of 'one interface, multiple implementations' - a cornerstone of good object-oriented design.