Evolving the wrapper classes

[Brian Goetz]

> Given your examples can we assume that the JVM will never need to do an implicit `Qjava/lang/Integer$val;` to `I` conversion? And these will always be explicit conversions performed by javac?
> 

Correct.

> > - The type [I is considered by the verifier to be equivalent to [java/lang/Integer$val. Array operations (aaload, iaload, etc.) support this.
> 
> Could you please explain the motivation behind this? Specifically, in which cases are iaload and aaload operations both performed on `[I` ? 
> 
> If `I` and `Qjava/lang/Integer$val;` will require explicit javac conversions, shouldn't `[I` and `[java/lang/Integer$val` also?
> 

Because arrays have identity (not to mention potentially large copying costs), there is simply no reasonable conversion we can define; any “conversion” would involve copying all the data, changing identity, or both.  Just as with the array subtyping requirements (Point[] <: Point.ref[] <: Object[]), these are things only the VM can do for us.  


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