Sometimes we write something for the book, only to realize it shouldn’t be in the book. This post is an example. Do you think this legal?
1 2 3 4 5 6 | public sealed interface MySealedClass permits MyRecord, MyEnum {}record MyRecord() implements MySealedClass {}enum MyEnum implements MySealedClass { VALUE } |
It is! A sealed interface can be implemented by any Java type. Which means records and enums are included.
Hi, Can you illustrate this with a working java code
Deepak: This is working Java code; it compiles. What do you mean? (Also, it is unlikely someone would write this code. It is meant to demonstrate legality)
I meant a real world scenario where this code work
Deepak: I can’t think of one. The point of the example is to show it is legal.
Hello, I miss the point why it shouldn’t be on the book – since it is legal code and that was what you wanted to demonstrate.
Peter: It is legal code. But it’s off topic for the exam. We can’t put everything in the book. So sometimes good stuff has to be cut. I didn’t want to leave this on the cutting room floor so I blogged about it.