virtual functions in java
In Java, the concept of virtual functions is related to polymorphism, and it is achieved through method overriding. Unlike some other programming languages (e.g., C++), Java doesn’t use the term “virtual function” explicitly. However, Java achieves the essence of virtual functions through dynamic method dispatch and method overriding.
Here’s how it works in Java:
1. Dynamic Method Dispatch: In Java, when a method is called on an object, the actual implementation that gets executed is determined at runtime based on the type of the object. This is known as dynamic method dispatch.
2. Method Overriding: Method overriding allows a subclass to provide a specific implementation of a method that is already defined in its superclass. When a subclass overrides a method, the version of the method in the subclass is the one that gets called at runtime.
Here’s an example to illustrate virtual functions in Java:
In this example:
Animalclass has a method
Catclasses are subclasses of
Animaland override the
- In the
mainmethod, two instances (
animal2) are created, and their types are determined at runtime. When calling
makeSoundon these instances, the actual method that gets executed is based on the runtime type of the objects (
Even though Java doesn’t explicitly use the term “virtual function,” the combination of dynamic method dispatch and method overriding achieves the same effect, allowing for polymorphic behavior where the appropriate method is determined at runtime based on the actual type of the object.