Does Java autobox when assigning an int to an Object?

Will the above code first wrap the int literal 8 in an Integer and then assign its reference to variable ob?

Yes. (Or rather, it will box the int value into an Integer object, and then assign the reference to the variable ob. The fact that the integer value is a literal is irrelevant here, really. It could be a method call returning int, for example.)

Because the java language specification has nothing on this case.

That’s not true. I mean, it doesn’t explicitly deal with assigning to Object, but it works the same way as normal conversions.

Section 5.1.7 of the specification deals with boxing, which would convert int to Integer… and then assigning an Integer reference to an Object variable is a normal reference conversion.

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