How to specify a constant is a byte or short?

Question

For the long data type, I can suffix a number with L to make the compiler know it is long. How about byte and short?

As motivation, the following yields a type-mismatch error:

List<Short> a = Arrays.asList(1, 2, 3, 4);

Answer 1

What you are actually talking about is an integer literal ( 1 ) versus a long literal ( 1L ). There is actually no such thing as a short or byte literal in Java. But it usually doesn't matter, because there is an implicit conversion from integer literals to the types byte, short and char. Thus:

final byte one = 1;  // no typecast required.

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The implicit conversion is only allowed if the literal is in the required range. If it isn't you need a type cast; e.g.

final byte minusOne = (byte) 255;  // the true range of byte is -128 .. +127

There are other cases where an explicit conversion is needed; e.g. to disambiguate method overloads, or to force a specific interpretation in an expression. In such cases you need to use a cast to do the conversion.

Your example is another of those cases.

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But the bottom line is that there is no Java syntax for expressing byte or short literals.

Answer 2

It's done automatically for you at the point of use

If an int literal is assigned to a short or a byte and it's value is within legal range, the literal is assumed to be a short or a byte.