16 bit hex string to signed int in Java

hex, java, parsing, signed

Solution

You can cast the `int` returned from `Integer.parseInt()` to a short:

short s = (short) Integer.parseInt("FFFF",16);
System.out.println(s);

Result:

-1

Problem

I have a string in Java representing a signed 16-bit value in HEX. This string can by anything from `"0000"` to `"FFFF"`. I use `Integer.parseInt("FFFF",16)` to convert it to an integer. However, this returns an unsigned value (`65535`). I want it to return a signed value. In this particular example `"FFFF"` should return `-1`. How can I achieve this? Since its a 16-bit value I thought of using `Short.parseShort("FFFF",16)` but that tells me that I am out of range. I guess `parseShort()` expects a negative sign.

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