FAQ: Generics: Lesson - Interfaces

This community-built FAQ covers the “Interfaces” exercise from the lesson “Generics: Lesson”.

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This exercise can be found in the following Codecademy content:

[BETA] Learn Intermediate Java

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for the 4th section of the exercise:
(Let’s create some references to our generic interfaces and output some data to the terminal…)

my answer:
Container containerRetriever = new Container<>(myNumber);
Book bookRetriever = new Book(bookName);

provided solution:
Retriever containerRetriever = new Container<>(myNumber);
Retriever bookRetriever = new Book(bookName);

My solution yields desired results, but i am wondering if it’s correct or not. Thank you for your time.

I hardly take anything in from this course so far (unlike with the Learn Java course). What is creating a “new Retriever”? It’s not a regular class, it’s an interface that simply allows your to “inherit” empty methods from it (I’d like to add that it has never been clearly explained by Codecademy why one may need any interfaces in the first place, let alone generic ones). Why is an interface now used to create objects all of a sudden? Folks at Codecademy, you should definitely rewrite the Learn Intermediate Java course from scratch, it’s a disgrace, frankly (not to mention silly mistakes like “it’s” instead of “its”, etc.)


hah :slight_smile: You are not alone. Feeling exactly the same way.
Why would I implement interface if rewrite it?
The program seem perfectly works without this.

And yeah, This is first time when interfaces being explaned

I cannot say yet, that the course need to be rewritten. Serialization was okay, I finished my project after that.
But with Interfaces I am frustrated :slight_smile: Hope it will be understood later