I'm working on my own implementation of the JVM and came around to the checkcast instruction. The full documentation is on this page. I'm curious because when enumerating the rules for how the cast works, one condition being checked is if the object reference being checked is of interface type. By my understanding, this shouldn't be possible; interfaces can't be directly instantiated, and any object that implements an interface has some other concrete class type. Am I missing something?

java interface casting jvm bytecode
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