@Override
    public int getLinkCount() {
        return links.size();
    }
@Test
    public final void testGetLinkCount() {
        assertEquals("initialy empty", 0, linkStore.getLinkCount());

        putLink(DID1, P1, DID2, P2, DIRECT);
        putLink(DID2, P2, DID1, P1, DIRECT);
        putLink(DID1, P1, DID2, P2, DIRECT);

        assertEquals("expecting 2 unique link", 2, linkStore.getLinkCount());
    }