by Method Overloading
Method overloading is a feature of many programming languages, including Java, C#, and C++, that allows a class to have multiple methods with the same name but with different parameters.
When a method is called, the compiler or interpreter determines which version of the method to call based on the number, type, and order of the arguments passed to the method. This process is known as compile-time or static polymorphism.
Method overloading is useful because it allows a class to have multiple methods with the same name that perform similar operations but on different data types. This can make the code more readable and easier to maintain.
When overloading a method, the return type of the method does not play a role in the determination of which method to call, it’s only based on the parameters passed to the method. Also, it’s important to notice that the accessibility level of the methods can be different.
Method overloading can also be achieved by changing the number of parameters in the method. For example, a class might have a method called “Calculate” that takes one parameter, and another version of the method called “Calculate” that takes two parameters.
Method Overriding
Method overriding is a feature of object-oriented programming languages, such as Java, C#, and C++, that allows a subclass or derived class to provide a different implementation of a method that is already provided by its superclass or base class.
When a method is overridden, the subclass’s method is called instead of the superclass’s method when the method is invoked on an instance of the subclass. This process is known as run-time or dynamic polymorphism.
Method overriding is useful because it allows a subclass to customize the behavior of a method inherited from its superclass, while still maintaining the same method signature. This can be used to implement a specific behavior for a certain type of object and reuse the common behavior of the parent class.
When overriding a method, the return type of the method must be the same as the return type of the overridden method, and the accessibility level of the method can’t be more restrictive than the overridden method.
Method overriding is achieved by using the “@override” annotation or the “override” keyword in some programming languages, to indicate that a method in a subclass is intended to override a method with the same name and signature in the superclass.
Important Differences Between Method Overloading and Overriding
There are a few important differences between method overloading and overriding:
- Method Signature: Method overloading is based on the method signature, which includes the method name and the number, type and order of the parameters. Method overriding is based on the method signature, which includes the method name and the parameter types, the return type of the method does not play a role in method overriding.
- Class Relationship: Method overloading occurs within the same class, while method overriding occurs between a base class and its derived class.
- Polymorphism: Method overloading is a form of compile-time or static polymorphism, where the method to be called is determined at compile-time based on the number, type and order of the arguments passed to the method. Method overriding is a form of run-time or dynamic polymorphism, where the method to be called is determined at runtime based on the actual type of the object.
- Accessibility: Method overloading can have different accessibility levels (public, private, protected) for the same method name but with different parameters, while method overriding can’t have a more restrictive accessibility level than the overridden method.
- Return Type: Method overloading doesn’t care about the return type, but in method overriding the return type must be the same as the overridden method.
- Use case: Method overloading allows a class to have multiple methods with the same name but with different parameters, this can make the code more readable and easier to maintain. Method overriding allows a subclass to customize the behavior of a method inherited from its superclass, while still maintaining the same method signature, this allows to implement a specific behavior for a certain type of object and reuse the common behavior of the parent class.
In conclusion, method overloading and overriding are two different concepts in object-oriented programming, they are based on different things, method overloading is based on the method signature and occurs within the same class, while method overriding is based on the method signature, which includes the method name and the parameter types
