How to Inherit Class in Java
In the world of object-oriented programming, inheritance is a fundamental concept that allows a class to inherit properties and behaviors from another class. This feature promotes code reusability and makes the code more organized and maintainable. Java, being one of the most popular programming languages, supports inheritance through its class hierarchy. In this article, we will discuss how to inherit class in Java, including the syntax and best practices.
Understanding Inheritance in Java
In Java, inheritance is achieved by using the `extends` keyword. When a class inherits from another class, it is known as a subclass or derived class, while the class being inherited from is called the superclass or base class. The subclass inherits all the non-private fields and methods of the superclass, which can be used directly in the subclass.
Syntax for Inheriting a Class in Java
To inherit a class in Java, you need to follow the following syntax:
“`java
public class SubClass extends SuperClass {
// subclass members
}
“`
Here, `SubClass` is the subclass that inherits from the `SuperClass`. You can add additional members (fields and methods) to the subclass as needed.
Example of Inheriting a Class in Java
Let’s consider an example where we have a superclass called `Animal` and a subclass called `Dog`. The `Animal` class has a method called `makeSound()`, and we want the `Dog` class to inherit this method.
“`java
public class Animal {
public void makeSound() {
System.out.println(“Animal makes a sound”);
}
}
public class Dog extends Animal {
// Dog class inherits the makeSound() method from Animal class
}
public class Main {
public static void main(String[] args) {
Dog dog = new Dog();
dog.makeSound(); // Output: Animal makes a sound
}
}
“`
In the above example, the `Dog` class inherits the `makeSound()` method from the `Animal` class. When we create an instance of the `Dog` class and call the `makeSound()` method, it prints the message “Animal makes a sound.”
Best Practices for Inheriting Classes in Java
1. Always use the `extends` keyword to define inheritance.
2. Choose meaningful names for the superclass and subclass.
3. Avoid deep inheritance hierarchies; instead, use composition and interfaces to achieve code reuse.
4. Use the `super()` keyword to call the constructor of the superclass when necessary.
5. Overriding methods should be done with caution, ensuring that the overridden method has the same signature and returns the same type as the superclass method.
By following these guidelines, you can effectively utilize inheritance in Java to create well-organized and reusable code.
