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CodeGym /Courses /Java Core /Interface tasks | Level 3

Interface tasks | Level 3

Java Core
Level 3, Lesson 2
Available

"Hello, Amigo! I've got great news for you! Tonight, you will definitely be in a good mood."

Kotlin

"Oh, why?"

"Yes. Because you're going to interfaces so well. Ha-ha-ha! Here are ten(!) tasks for you. Don't be bored, Amigo!"

3
Task
Java Core, level 3, lesson 2
Locked
Beer
Beer
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3
Task
Java Core, level 3, lesson 2
Locked
Beer. Part 2. The recovery.
Beer. Part 2. The recovery.
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3
Task
Java Core, level 3, lesson 2
Locked
Don't mix beer with cola
Don't mix beer with cola
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3
Task
Java Core, level 3, lesson 2
Locked
Selectable and Updatable
Selectable and Updatable
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8
Task
Java Core, level 3, lesson 2
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Four mistakes
Four mistakes
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8
Task
Java Core, level 3, lesson 2
Locked
Buggy initializeIdAndName
Buggy initializeIdAndName
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3
Task
Java Core, level 3, lesson 2
Locked
Parameterized interface
Parameterized interface
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3
Task
Java Core, level 3, lesson 2
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Hey, are you alive?
Hey, are you alive?
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3
Task
Java Core, level 3, lesson 2
Locked
All that moves
All that moves
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3
Task
Java Core, level 3, lesson 2
Locked
Future manager
Future manager
Open
Comments (43)
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Thomas Level 13, Scottsdale, United States
12 August 2024
Output Alcoholic beverage
Heiden133 Level 19, Germany
11 March 2024
Why these tasks are so easy compared to what we had to do in AP Java Course?
Anonymous #10782038 Level 24, United States of America
1 April 2024
its also weird that the last two sections are the same as the first two in this. And it wont let me unlock sections I already did in AP java..
Vasile Durlesteanu Level 22
21 June 2024
So true
Vasile Durlesteanu Level 22
21 June 2024
True
Michael Amann Level 22, United States of America, United States
25 May 2022
A Matrix reference! It's about time!
Michael Amann Level 22, United States of America, United States
24 May 2022
At least it's BEER this time! 😁
proegg123 Level 16, Slovakia
17 January 2022
isnt it enough for Boss to extend HasManagementPotential since HasManagementPotential already has Person in itself?
aijo Level 30, Germany, Germany
4 February 2022
but it doesn't in the task code, so we need to implement both. in theory, I think extending Person interface should also work, but it would lower the flexibility of the interface. what about cats and robots with management potential? ;) they'd need a separate interface then, as non-persons. also, hello to Slovakia, from a fellow Slovak living in Germany!
proegg123 Level 16, Slovakia
9 February 2022
Hello back! :)
DarthGizka Level 24, Wittenberg, Germany
3 June 2021
task1306 (Buggy initializeIdAndName) caveat: simply returning a User (i.e. this) from initializeIdAndName() as stated in the requirements is not sufficient; in order for the code to pass the declared type of the result must also be User, not DBObject (covariant return).
Vazhiko Level 2
11 February 2025
Danke sehr!
Jurij Thmsn Level 29, Flensburg, Germany
15 February 2021
Bulldozed through these exercises without help, but still don't have the feeling that I get it. Hope it is part of the process and will get clearer in the future ...
ayhem bouabid Level 25, Tunis, Tunisia
11 January 2021
The task with Double as a return type instead of double is a tricky one !!
Oliver Heintz Level 18, Mustang, United States
30 November 2020
I feel as if I almost know what I'm doing. And then something really silly seems to stump me. But then I figure it out in a few minutes, and I feel stupid, but... I figured it out in a few minutes, so maybe that's ok? I'm a math teacher who, back in May, had ZERO programming experience, and I'm really hoping that next May I can quit teaching math for good because I'm finally good enough to support myself doing this.
Donny Level 15, San Francisco, United States
31 January 2021
Good luck to you, Oliver. I'm trying to do the same--that is, create an income source for my partner and myself. Best wishes, Donny
Chandan Thapa Level 22, Dubai, United Arab Emirates
21 November 2020
Things are getting real now! :)