MD5 for java

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

/**
 * @author BABUKUMA
 */
public final class Digest {
    public static byte[] md5(final String data) throws NoSuchAlgorithmException {
        MessageDigest md = MessageDigest.getInstance("MD5");
        byte[] dat = data.getBytes();
        md.update(dat);
        return md.digest();
    }

    // MD5　ハッシュ関数
    private static String hashByte2MD5(byte[] hash) {
        StringBuilder hexString = new StringBuilder();
        for (byte b : hash) {
            if ((0xff & b) < 0x10) {
                hexString.append("0" + Integer.toHexString((0xFF & b)));
            } else {
                hexString.append(Integer.toHexString(0xFF & b));
            }
        }

        return hexString.toString();
    }

    public static String md5String(final String data)
            throws NoSuchAlgorithmException {
        return hashByte2MD5(md5(data));
    }
}