InfoWorld

When to use abstract classes vs. interfaces in Java

Abstract classes and interfaces in Java serve fundamentally different purposes. Learn the differences between these Java language elements and how to use them in your programs. Abstract classes and ...
InfoWorld

Abstract class versus interface in the JDK 8 era

In The new Java 8 Date and Time API: An interview with Stephen Colebourne, Stephen Colebourne tells Hartmut Schlosser, “I think the most important language change isn’t lambdas, but static and default ...
TheServerSide

Use sealed classes in Java to control your inheritance

Imagine you are an expert object-oriented Java developer who meticulously crafts code the way an artist cares for their masterpiece. You believe clean code is an absolute necessity. Classes with clear ...
Ars Technica

Java - Can an interface define a class?

Obviously that doesn't compile, but I hate to make a file FooType.java with just the 5 lines above in it. Obviously that doesn't compile, but I hate to make a file ...
InfoQ

Java Feature Spotlight: Sealed Classes

The release of Java SE 15 in Sept 2020 will introduce "sealed classes" (JEP 360) as a preview feature. A sealed class is a class or interface which restricts which other classes or interfaces may ...