Why Use \"List list\" Over \"ArrayList list\" for Polymorphism?

Using "List list" Instead of "ArrayList list" for Polymorphism

When dealing with collections, one may encounter the choice between declaring a variable as "List list" or "ArrayList list." While ArrayList inherits from the List interface, understanding the reasons behind using the former is crucial for effective polymorphism.

Firstly, using "List list" decouples the code from a specific implementation. By declaring it as an interface rather than the specific class, the code remains flexible and allows for the effortless switching of different List implementations, such as LinkedList.

This design pattern is particularly beneficial in larger projects or libraries, where implementation changes might be necessary in the future. By programming to the interface, altering the underlying implementation becomes a simple matter without compromising existing code.

In contrast, if the variable is declared as "ArrayList list," the code becomes tightly coupled to the ArrayList implementation. Any changes to the underlying class may lead to errors or unexpected behavior if the code relies on class-specific methods.

In essence, utilizing "List list" promotes polymorphism, offering flexibility and ease of maintenance when dealing with collections. It decouples the code from specific implementations and empowers developers to adapt to changes in the underlying data structure, ensuring code longevity and extensibility.

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