String to SHA-1

Main.java

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class Main {
    public static void main(String[] args) {
        String plain = "example";
        System.out.println("Plain: " + plain);
        try {
            System.out.println("SHA-1: " + AeSimpleSHA1.SHA1(plain));
        } catch (NoSuchAlgorithmException ex) {
            ex.printStackTrace();
        } catch (UnsupportedEncodingException ex) {
            ex.printStackTrace();
        }
    }
}

class AeSimpleSHA1 {
    private static String convertToHex(byte[] data) {
        StringBuilder buf = new StringBuilder();
        for (byte b : data) {
            int halfbyte = (b >>> 4) & 0x0F;
            int two_halfs = 0;
            do {
                buf.append((0 <= halfbyte) && (halfbyte <= 9) ? (char) ('0' + halfbyte) : (char) ('a' + (halfbyte - 10)));
                halfbyte = b & 0x0F;
            } while (two_halfs++ < 1);
        }
        return buf.toString();
    }

    public static String SHA1(String text) throws NoSuchAlgorithmException, UnsupportedEncodingException {
        MessageDigest md = MessageDigest.getInstance("SHA-1");
        md.update(text.getBytes("UTF-8"), 0, text.getBytes("UTF-8").length);
        byte[] sha1hash = md.digest();
        return convertToHex(sha1hash);
    }
}