Convert String to Bytes in Java

Question

Possible Duplicate:
Convert a string representation of a hex dump to a byte array using Java?

I got an MD5 String

de70d4de8c47385536c8e08348032c3b

and I need it as the Byte Values

DE 70 D4 DE 8C 47 38 55 36 C8 E0 83 48 03 2C 3B

This should be similar to Perls pack("H32); function.

Answer 1

There are many ways to do this. Here is one:

public static void main(String[] args) {

    String s = "de70d4de8c47385536c8e08348032c3b";

    Matcher m = Pattern.compile("..").matcher(s);

    List<Byte> bytes = new ArrayList<Byte>();
    while (m.find())
        bytes.add((byte) Integer.parseInt(m.group(), 16));

    System.out.println(bytes);
}

Outputs (-34 == 0xde):

[-34, 112, -44, -34, -116, 71, 56, 85, 54, -56, -32, -125, 72, 3, 44, 59]