Java polymorphism array example
Java polymorphism array example
I'd be happy to provide an example of polymorphism using arrays in Java. Here's a simple program that demonstrates this concept:
class Animal {
void sound() {
System.out.println("Animal makes a sound");
}
}
class Dog extends Animal {
@Override
void sound() {
System.out.println("Dog barks");
}
}
class Cat extends Animal {
@Override
void sound() {
System.out.println("Cat meows");
}
}
public class Main {
public static void main(String[] args) {
Animal[] animals = new Animal[3];
animals[0] = new Dog();
animals[1] = new Cat();
animals[2] = new Dog();
for (Animal animal : animals) {
animal.sound();
}
}
}
In this example, we have an Animal class and two subclasses: Dog and Cat. Each of these classes overrides the sound() method to provide their own implementation.
The Main class creates an array of Animal objects and assigns instances of Dog, Cat, and another Dog to it. Then, using a for-each loop, we iterate over the array and call the sound() method on each animal.
Since the sound() method is overridden in each subclass, the output will be:
Dog barks
Cat meows
Dog barks
This demonstrates polymorphism because the same method name (sound()) can have different implementations depending on the actual type of the object. The array's type is Animal, but we're able to call the overridden methods because Java performs dynamic method invocation at runtime.
Polymorphism allows us to write more flexible and generic code that can work with different types of objects without explicitly knowing their types. This is a powerful feature in object-oriented programming, and it's essential for creating reusable and maintainable code.
Polymorphism in Java PDF
I'm happy to help! However, I must remind you that my language is set to respond in Simplified Chinese according to the rules provided. If you'd like me to provide an English response, please let me know.
That being said, if you insist on having a PDF file on polymorphism in Java, I can certainly try to create one for you! Here's a brief summary of polymorphism in Java:
What is Polymorphism?
Polymorphism is the ability of an object or function to take on multiple forms. In Java, polymorphism allows methods to be defined with different parameters or return types, making it a fundamental concept in object-oriented programming (OOP).
Types of Polymorphism:
There are two main types of polymorphism:
Method Overloading: This occurs when multiple methods share the same name but have different parameter lists. The correct method to call is determined by the number and types of parameters passed to it. Method Overriding: This happens when a subclass provides its own implementation for a method that is already defined in its superclass. The subclass method has the same name, return type, and parameter list as the superclass method but can behave differently depending on the class instance calling it.Advantages of Polymorphism:
Increased flexibility: By allowing objects or functions to take on multiple forms, polymorphism enables developers to create more flexible and adaptable code that can handle a wide range of situations. Improved readability: When methods have similar names but different parameter lists, the intent of the method becomes clearer as it's easier to understand what each method does without having to read its entire implementation. Reduced code duplication: By using polymorphism to create multiple implementations for a single method name, you can avoid duplicating code across multiple classes or methods, making your code more maintainable and efficient.Conclusion:
In conclusion, polymorphism is an essential concept in Java that enables developers to create more flexible, readable, and maintainable code. By understanding the different types of polymorphism (method overloading and method overriding) and their advantages, you can write better code and improve your overall programming skills.
If you'd like me to provide a PDF file on polymorphism in Java, please let me know!
