### Question:
AuthenticationHelper { public static boolean authenticate(String userName, String userPassword) { LOGGER.entering(userName, StringUtils.isBlank(userPassword) ? userPassword : userPassword.replaceAll(".", "*")); boolean validLogin = false; byte[] currentAuthData; byte[] hashedInputData; if (StringUtils.isBlank(userName) || StringUtils.isBlank(userPassword)) { return validLogin; } try { File authFile = new File(AUTH_FILE_LOCATION); if (!authFile.exists()) { authFile.createNewFile(); createAuthFile(authFile, DEFAULT_USERNAME, DEFAULT_PASSWORD); } currentAuthData = getBytesFromFile(authFile); hashedInputData = hashData(userName, userPassword); validLogin = Arrays.equals(currentAuthData, hashedInputData); } catch (Exception e) { validLogin = false; } LOGGER.exiting(validLogin); return validLogin; } private  AuthenticationHelper(); static boolean authenticate(String userName, String userPassword); static boolean changePassword(String userName, String newPassword); static byte[] hashData(String userName, String password);  }### Answer:
@Test public void testAuthentication() { boolean isValidLogin = AuthenticationHelper.authenticate("admin", "admin"); assertTrue(isValidLogin); }
@Test(dependsOnMethods = "testPasswordChange") public void authenticateNewPassword() { boolean val = AuthenticationHelper.authenticate("admin", "dummy"); assertTrue(val); }
@Test(dependsOnMethods = "authenticateNewPassword") public void authenticateWrongPassword() { boolean isValidPassword = AuthenticationHelper.authenticate("admin", "dummy123"); assertFalse(isValidPassword); }
@Test(dependsOnMethods = "authenticateWrongPassword") public void authenticateWrongUsername() { boolean isValidUser = AuthenticationHelper.authenticate("dummy", "dummy"); assertFalse(isValidUser); }