Question

Ok, as of Java 6 there is no y literal suffix. Consider this code:

byte b = some_byte();
switch (b) {
    case (byte) 0x80: ...
    case (byte) 0x81: ...

and this alternative:

int b = some_byte() & 0xff;
switch (b) {
    case 0x80: ...
    case 0x81: ...

Which would you use? In the first case, are (byte) casts performed during run time or compile time? Thanks.

Answer 1

Which would you use?

Probably the latter, just for simplicity – but with a comment to explain what’s going on.

In the first case, are (byte) casts performed during run time or compile time?

Compile-time. Don’t forget that case values have to be compile-time constants anyway.

Another option is to create constants for these things:
private static final byte FOO = (byte) 0x80;
private static final byte BAR = (byte) 0x81;

...

switch (someByte()) {
    case FOO:
    case BAR:
        ...
}

Aside from anything else, that makes the values less “magic”.

Or you could possibly even use an enum…