[Demonstration 1]

[Buggy Method]
private byte[] getHash(File file) {
    try {
        MessageDigest md = MessageDigest.getInstance("SHA-256");
        BufferedInputStream in = new BufferedInputStream(new FileInputStream(file));
        int count = 0;
        byte[] buffer = new byte[1024 * 1024];
        while ((count = in.read(buffer)) > 0) {
            md.update(buffer, 0, count);
        }
        in.close();
        return md.digest();
    } catch (NoSuchAlgorithmException | IOException e) {
        e.printStackTrace();
    }
    return null;
}

[Buggy Hunk]
MessageDigest md = MessageDigest.getInstance("SHA-256");

[Patch]
MessageDigest md = MessageDigest.getInstance(MonitoringConstants.HASH_ALGORITHM);

[Demonstration 2]

[Buggy Method]
@Override
public void onDateSet(DatePicker datePicker, int year, int month, int day) {
    mYear = year;
    mMonth = month;
    mDay = day;
    mDate = mDay + "-" + mMonth + "-" + mYear;
    dateButton.setText(mDate);
}

[Buggy Hunk]
dateButton.setText(mDate);

[Patch]
followupDateButton.setText(mDate);

[Demonstration 3]

[Buggy Method]
public static String decrypt(String message, String key) {
    try {
        byte[] realMessage = mBase.decode(message);
        final MessageDigest md = MessageDigest.getInstance("md5");
        final byte[] digestOfPassword = md.digest(key.getBytes("utf-8"));
        final byte[] keyBytes = Arrays.copyOf(digestOfPassword, 24);
        for (int j = 0, k = 16; j < 8; ) {
            keyBytes[k++] = keyBytes[j++];
        }
        final SecretKey keySecret = new SecretKeySpec(keyBytes, "DESede");
        final IvParameterSpec iv = new IvParameterSpec(new byte[8]);
        final Cipher decipher = Cipher.getInstance("DESede/CBC/PKCS5Padding");
        decipher.init(Cipher.DECRYPT_MODE, keySecret, iv);
        // final byte[] encData = new
        // sun.misc.BASE64Decoder().decodeBuffer(message);
        final byte[] plainText = decipher.doFinal(realMessage);
        return new String(plainText, StandardCharsets.UTF_8);
    } catch (Exception e) {
        e.printStackTrace();
    }
    return "FAIL";
}

[Buggy Hunk]
byte[] realMessage = mBase.decode(message);

[Patch]
byte[] realMessage = mBase.decode(message.getBytes());