multimap.put("foo", 3);
    multimap.put("foo", -1);
    multimap.put(null, null);
    multimap.put("bar", 1);
    multimap.put("foo", 2);
    multimap.put(null, 0);
    multimap.put("bar", 2);
    multimap.put("bar", null);
    multimap.put("foo", null);
    multimap.put("foo", 4);
    multimap.put(null, -1);
    multimap.put("bar", 3);
    multimap.put("bar", 1);
    multimap.put("foo", 1);

    assertTrue(multimap().containsValue(null));
  }

  @MapFeature.Require(ALLOWS_NULL_VALUE_QUERIES)
  public void testContainsNullValueNo() {
    assertFalse(multimap().containsValue(null));
  }

  @MapFeature.Require(absent = ALLOWS_NULL_VALUE_QUERIES)
  public void testContainsNullValueFails() {
    assertThrows(NullPointerException.class, () -> multimap().containsValue(null));
  }

       * since the Equivalence base type now implements this logic itself
       */
      assertTrue(item + " must be inequivalent to null", !equivalence.equivalent(item, null));
      assertTrue("null must be inequivalent to " + item, !equivalence.equivalent(null, item));
      assertTrue(item + " must be equivalent to itself", equivalence.equivalent(item, item));
      assertEquals(

  /**
   * The collection must not throw {@code NullPointerException} on calls such as {@code
   * contains(null)} or {@code remove(null)}, but instead must return a simple {@code false}.
   */
  ALLOWS_NULL_QUERIES,
  ALLOWS_NULL_VALUES(ALLOWS_NULL_QUERIES),

  /**
   * Indicates that a collection disallows certain elements (other than {@code null}, whose validity

       * since the Equivalence base type now implements this logic itself
       */
      assertTrue(item + " must be inequivalent to null", !equivalence.equivalent(item, null));
      assertTrue("null must be inequivalent to " + item, !equivalence.equivalent(null, item));
      assertTrue(item + " must be equivalent to itself", equivalence.equivalent(item, item));
      assertEquals(

            if (uploadFile == null) {
                throwValidationError(messages -> messages.addErrorsDesignFileNameIsNotFound("designFileName"), this::asListHtml);
                return null;
            }
        } else {
            throwValidationError(messages -> messages.addErrorsDesignFileIsUnsupportedType("designFileName"), this::asListHtml);
            return null;
        }

        Smb2NegotiateResponse r = null;
        byte[] negoReqBuffer = null;
        byte[] negoRespBuffer = null;
        try {
            smb2neg.setRequestCredits(Math.max(1, this.desiredCredits - this.credits.availablePermits()));

            final int reqLen = negotiateWrite(smb2neg, first != null);

            spec = "smb1:////";
            limit += 2;
        } else if (!spec.startsWith("smb1://") && host != null && host.length() == 0) {
            spec = "//" + spec;
            limit += 2;
        }
        super.parseURL(u, spec, start, limit);
        path = u.getPath();
        ref = u.getRef();
        if (ref != null) {
            path += '#' + ref;
        }
        port = u.getPort();
        if (port == -1) {

    }

    @Test
    @DisplayName("initSecContext with null buffer and non-zero len throws NPE")
    void testInitSecContextNullBufferNonZeroLen() throws Exception {
        SpnegoContext ctx = newContext();
        // A null buffer with non-zero len leads to NPE while slicing input
        assertThrows(NullPointerException.class, () -> ctx.initSecContext(null, 0, 1));

   * the putIfAbsent returns a non-null value, and the case where the replace() of an observed zero
   * fails.
   */
  public void testAdd_withFailures() {
    AtomicInteger existing = new AtomicInteger(12);
    AtomicInteger existingZero = new AtomicInteger(0);

    // initial map.get()
    when(backingMap.get(KEY)).thenReturn(null);
    // since get returned null, try a putIfAbsent; that fails due to a simulated race