@Test
    void testThatSessionIdIsUniquePerQuery() {
        Query q = new Query();
        assertNull(q.getSessionId());
        assertNull(q.getSessionId());
        SessionId s1 = q.getSessionId("node-0");
        assertNotNull(s1);
        SessionId s2 = q.getSessionId("node-0");
        assertNotSame(s1, s2);
        assertEquals(s1, s2);
        assertEquals(s1.toString(), s2.toString());

        Query q2 = new Query();
        assertNotEquals(q.getSessionId(), q2.getSessionId("node-0"));
        assertNotEquals(q.getSessionId().toString(), q2.getSessionId("node-0").toString());
    }
Test that we get the last value if a parameter is assigned multiple times
container-search/src/test/java/com/yahoo/search/test/QueryTestCase.java