public abstract String encrypt(String plaintext) throws GeneralSecurityException;
@Test
    void encrypt() throws GeneralSecurityException {
        // given
        RunContext runContext = runContextFactory.of();
        String plainText = "toto";

        String encrypted = runContext.encrypt(plainText);
        String decrypted = EncryptionService.decrypt(secretKey, encrypted);

        assertThat(encrypted, not(plainText));
        assertThat(decrypted, is(plainText));
    }