Abstract classes and interfaces are plentiful in Java code, and even in the Java Development Kit (JDK) itself. Each code element serves a fundamental purpose: Interfaces are a kind of code ...

By allowing developers to define closed hierarchies, sealed classes improve code safety, clarity and maintainability. Sealed classes make Java an even more powerful and expressive language and set the ...

Suppose we have a class which needs to allow controlled access to one of its private methods. Below is the class defining this method and describing two ways (Reflection / MethodHandle) to access it.

However, seasoned Java developers know that sometimes the simplest of language constructs can turn out to be the most powerful, as is the case with object models designed with abstract classes and ...