javastringhex

Java converting int to hex and back again

I have the following code...

int Val=-32768;
String Hex=Integer.toHexString(Val);

This equates to ffff8000

int FirstAttempt=Integer.parseInt(Hex,16); // Error "Invalid Int"
int SecondAttempt=Integer.decode("0x"+Hex);  // Error "Invalid Int"

So, initially, it converts the value -32768 into a hex string ffff8000, but then it can't convert the hex string back into an Integer.

In .Net it works as I'd expect, and returns -32768.

I know that I could write my own little method to convert this myself, but I'm just wondering if I'm missing something, or if this is genuinely a bug?

Solution

  • It overflows, because the number is negative.

    Try this and it will work:

    int n = (int) Long.parseLong("ffff8000", 16);