Wrapper classes - why integer literals fail for Long but work for anything smaller

Question

Just trying to understand auto-boxing, which I do apart from one thing:

Short s = 250;
Long l = 250;

The assignment to Long l

Answer 1

Ideally, no auto narrowing should be allowed.

But since there are no byte/short literals, we can't write

byte b = 0b;

and it seems silly to

byte b = (byte)0;

so auto narrowing of constant integer is allowed so we can write

byte b = 0;

which is carried over to autoboxing case.

For long/Long, since there are long literals, this is less of a problem. Still, it should be allowed, since auto widening of signed integer is always safe.