"short s = 2;" Does Java already understand 2 as short?

Question

I know that by default when initializing a variable of an integer type Java classifies it as int, but in the case of short s = 2, Java already understands 2 as short? Or is there some conversion?

Answer 1

There is no conversion, but there is one cast implicit, so even though technically its literal is a int, if it can be considered a short this will be done by the compiler when generating the code. The compiler knows how to understand the int as if it were a short at no cost. A cast can be performed by the compiler without implying in code to be executed, therefore without conversion. In memory only 2 bytes will be reserved and the number will be encoded in this way without losses or conversions (if it fits in the track of this type, you cannot do this if the number escapes from the track).

Not all cast generates conversion, the compiler makes effort to only interpret in the different way he needs in that context, in some cases not being possible he will make a conversion, but it is not this case, he knows he can only interpret that number as a short.