uml - Can a class extend an abstract class and implement an interface at the same time? (java) - Stack Overflow

If I have for example a class Foo and also an abstract class Bar and an interface Fizz, can the class implement both in its declaration? Or should the interface first be implemented in the abstract

How to show relation between interfaces and classes in UML? - Stack Overflow

JUnit 5 User Guide

design principles - Is Inheritance as Specialization hurt? And how can it be fixed? - Software Engineering Stack Exchange

java - How to present abstract class which has relationship with interface class in class diagram - Stack Overflow

Groovy Language Documentation

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java - Moving methods from Abstract classes to Interfaces to improve code design - Stack Overflow

clean code - How to use the Decorator pattern to add little functionality to big objects? - Software Engineering Stack Exchange

What is an Abstract Class in Java and How to Implement It?

Answered: Convert the UML class diagram into Java…

Groovy Language Documentation

Mastering Abstraction in Java. Unveiling the Power of Abstract Classes…, by Cognitive Creator, Oct, 2023

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object oriented - Is casting between interfaces the best approach for capability discovery when using interface inheritance? - Software Engineering Stack Exchange