public List<Protocol> find() {
        return this.find(Protocol::isEnabled);
    }
@Test
    public void testGetProtocols() {
        final TestProtocol defaultProtocol = new TestProtocol(Scheme.ftp);
        final TestProtocol providerProtocol = new TestProtocol(Scheme.ftp) {
            @Override
            public String getProvider() {
                return "c";
            }
        };
        final TestProtocol disabledProtocol = new TestProtocol(Scheme.sftp) {
            @Override
            public boolean isEnabled() {
                return false;
            }
        };
        final ProtocolFactory f = new ProtocolFactory(new HashSet<>(
                Arrays.asList(defaultProtocol, providerProtocol, disabledProtocol)));
        final List<Protocol> protocols = f.find();
        assertTrue(protocols.contains(defaultProtocol));
        assertTrue(protocols.contains(providerProtocol));
        assertFalse(protocols.contains(disabledProtocol));
    }