@Test public void testVerificationToken() { SecurityTools securityTools = Mockito.mock(SecurityTools.class); when(securityTools.generateRandomString(Mockito.anyInt())).thenReturn("TOKEN"); UserTools userTools = new UserTools(); userTools.setSecurityTools(securityTools); User user = new User("*****@*****.**", "12345"); userTools.generateVerificationToken(user); assertNotNull(user.getVerificationToken()); assertFalse(user.getVerificationToken().isEmpty()); }