cast<R> abstract method Null safety

Queue<R> cast<R>()
override

Provides a view of this queue as a queue of R instances, if necessary.

If this queue contains only instances of R, all read operations will work correctly. If any operation tries to access an element that is not an instance of R, the access will throw instead.

Elements added to the queue (e.g., by using addFirst or addAll) must be instances of R to be valid arguments to the adding function, and they must also be instances of E to be accepted by this queue as well.

Methods which accept Object? as argument, like contains and remove, will pass the argument directly to the this queue's method without any checks. That means that you can do queueOfStrings.cast<int>().remove("a") successfully, even if it looks like it shouldn't have any effect.

Implementation

Queue<R> cast<R>();