Question

this has been driving me nuts because i know theres a simple solution but i cant find it…

I have a edittext field that askes for an Hexadecimal number, the textfield is restricted to only receiving 0-9, a,b,c,d,e,f.

How do i convert this string to the actual number?

Example:
String = 0F => int = 0F or possibly => 0000 1111.

I’m trying to store MAC-addresses and then manipulating them and i only know how to store strings into SQLite! 🙂

Answer 1

Integer.parseInt(String s, int radix) is what you want. Pass in 16 as the radix. Read the docs here.

For MAC addresses, you may find that Integer isn’t a large enough type, so try the Long equivalent instead.

And if even Long isn’t big enough, or you want arbitrarily large precision, then use BigInteger instead. You can pass the radix to the constructor: public BigInteger(String val, int radix).

And for even more flexibility, look at the IntegerValidator provided by Apache Commons.