public Host lookup(final String uuid) {
        return this.stream().filter(h -> h.getUuid().equals(uuid)).findFirst().orElse(null);
    }
@Test
    public void testLookup() {
        final AbstractHostCollection c = new AbstractHostCollection() {
        };
        final Host bookmark = new Host(new TestProtocol());
        assertFalse(c.find(new AbstractHostCollection.HostComparePredicate(bookmark)).isPresent());
        assertNull(c.lookup(bookmark.getUuid()));
        c.add(bookmark);
        assertTrue(c.find(new AbstractHostCollection.HostComparePredicate(bookmark)).isPresent());
        assertNotNull(c.lookup(bookmark.getUuid()));
    }