public static FingerprintTrustManagerFactoryBuilder builder(String algorithm) {
        return new FingerprintTrustManagerFactoryBuilder(algorithm);
    }
@Test
    public void testWithNoFingerprints() {
        assertThrows(IllegalStateException.class, new Executable() {
            @Override
            public void execute() {
                FingerprintTrustManagerFactory.builder("SHA-256").build();
            }
        });
    }