Hex to integer (4 bytes)

Question

I'm working with ZigBee, I receive data from a sensor of a end device, and I want to convert from hex to int. The data are from 4bytes, this information is regarding the battery, an example of what I get would be this: "00 00 00 e1" (but without blanks) and I need to pass this on to voltages, but first I think I need to pass it to int.

Anyone can help me please? I'm doing my application for Android.

Thank you in advance.

Answer 1

int n = (int)Long.parseLong(st.replaceAll("\\s+",""), 16);

(where st is your string) does it. Two things:

The replaceAll strips out any white space.

I go via the Long parser to circumvent NumberFormatExceptions for negatives

Answer 2

Use Integer.parseInt() for this:

Parses the string argument as a signed integer in the radix specified by the second argument

Example:

Integer.parseInt("-FF", 16) // pass 16 to indicate an hexadecimal value
=> -255

Answer 3

Integer.parseInt("ff0000", 16)