java - Parsing <T extends Interface<T>> and ending a potential infinite cycle -


consider class definition starts

class pokemon extends playable<pokemon>

this similar more common class pokemon implements comparable<pokemon>, imposes total ordering on pokemons.

although have been seeing , writing time, realized (after fielding question) theoretical standpoint @ least, there risk of infinite loop in parsing if 1 not careful.

consider this:
step 1: compiler or classloader tries parse (or load) pokemon, sees needs parse playable<.> first.
step 2: compiler realizes because playable parameterized pokemon, needs load or parse pokemon. find ourselves going step 1, , never-ending cycle established.

in practice, know not case, because works. how cycle broken? theory @ end of step 2, compiler or classloader stops , use "reference" pokemon instead of pulling pokemon source code. don't know enough javac or classloaders affirm this. weigh in?

this similar "loop" in declaration:

class linkedlistnode {     private string data;     private linkedlistnode next;     ... }

in order process private linkedlistnode next field, compiler needs know linkedlistnode type. not need have complete type @ point, because type name provides enough information declare field.

similarly, when declare generic class refers own type part of inheritance structure, compiler not need complete type finish parsing declaration.


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