In object-oriented programming (OOP), polymorphism refers to an object’s ability to take more than one form. The term “polymorphism” comes from the Greek words “poly” (meaning “many”) and “morph” (meaning “forms”) and shows how polymorphic objects can execute different operations, depending on the context.
OOP refers to a programming approach that focuses on the use of objects. Essentially, objects are defined by the way they behave, also known as a method and their attributes. With OOP, programmers further define and differentiate objects by creating classes of objects. Java also allows the creation of a subclass which is a newly created class that inherits attributes of an already established class. The original class from which these attributes were copied from are called superclasses.
What are the types of polymorphism in Java?
Polymorphism in Java is one of the core concepts of OOP. It allows programmers to write consistent code that can behave differently depending on the superclass or subclass that the method or object is interacting with.
There are two types of polymorphism in Java:
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Compile-time polymorphism
Also known as static polymorphism, this type of polymorphism is resolved during code compilation when the code becomes machine instruction. It is typically achieved through overloading when multiple methods in the same class have the same name but different parameters. This allows a class to perform a similar operation differently, depending on the input. Compile-time polymorphism offers faster execution times and reusability because the method to be executed is determined at compile time. However, it lacks flexibility since all possible method instructions must be known at compile time, making it less adaptable to changes.
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Run-time polymorphism
Run-time polymorphism, also known as dynamic binding or late binding, is a type of polymorphism that is resolved during program execution. This type of polymorphism is typically achieved through method overriding, wherein a subclass provides a specific implementation of a method that is already defined in its superclass. The method to be executed is determined at runtime, allowing for more adaptability and flexibility in the code. However, this leads to slower execution times than compile-time polymorphism due to the machine determining the method at runtime.
What are the benefits of polymorphism?
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Reusability
Polymorphism allows for designing more flexible and reusable code. It enables programmers to create code that will work with objects regardless of each object’s specific class.
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Flexibility
Instead of having to modify codes, polymorphism allows programmers to extend functionality easily.
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Simplified code
Polymorphism allows programmers to create more concise code. Polymorphic codes are simple because they keep the exact initial instruction but have the capability to change themselves.
What are the downsides of polymorphism?
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Performance issues
A machine might struggle to run a polymorphic code, especially when it becomes too complex.
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Difficult to implement
Polymorphic codes are more difficult to implement due to the amount of variables.
Conclusion
As one of the core elements of OOP, polymorphism offers programmers a way to create flexible code that can be easily extended or adapted. Polymorphism simplifies the interaction between methods and classes to ensure more consistent, flexible, and reusable code. Understanding and properly implementing polymorphism can lead to improving efficiency when it comes to coding and programming.
