Use Java assertions to test your assumptions about program correctness and check them in your code.

A method might accept a specific type and its subclasses, but you want to restrict usage to a select few implementations of your own design. Java's open inheritance model can feel like an open ...

Method and variable handles vs. Java reflection To truly understand MethodHandles and VarHandles —what they do and why they are useful—it’s helpful to know a few things about reflection in Java.