public void testClear() {
    collection.clear();
    assertTrue("After clear(), a collection should be empty.", collection.isEmpty());
    assertEquals(0, collection.size());
    assertFalse(collection.iterator().hasNext());
  }

  @CollectionFeature.Require(absent = SUPPORTS_REMOVE)
  @CollectionSize.Require(absent = ZERO)
  public void testClear_unsupported() {
    try {
      collection.clear();
      fail(

  public void testClearClearsInverse() {
    BiMap<V, K> inv = getMap().inverse();
    getMap().clear();
    assertTrue(getMap().isEmpty());
    assertTrue(inv.isEmpty());
  }

  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testKeySetClearClearsInverse() {
    BiMap<V, K> inv = getMap().inverse();
    getMap().keySet().clear();
    assertTrue(getMap().isEmpty());
    assertTrue(inv.isEmpty());
  }

    @Override
    protected boolean isUseOneTimeContainer() {
        return true;
    }

    public void test_maxUsernameLength() throws IOException {
        FessProp.propMap.clear();
        FessConfig fessConfig = new FessConfig.SimpleImpl() {
            @Override
            public Integer getLdapMaxUsernameLengthAsInteger() {
                return Integer.valueOf(-1);
            }
        };

        list.clear();
        authenticator.addGroupOrRoleName(list, "test", true);
        assertEquals(1, list.size());
        assertEquals("test", list.get(0));

        list.clear();
        authenticator.addGroupOrRoleName(list, "test", false);
        assertEquals(1, list.size());
        assertEquals("test", list.get(0));

        list.clear();

        } else {
            this.inactiveProfileIds.clear();
        }
    }

    public void setProfiles(List<Profile> profiles) {
        if (profiles != null) {
            this.profiles = new ArrayList<>(profiles);
        } else {
            this.profiles.clear();
        }
    }

    public void addProfile(Profile profile) {
        profiles.add(profile);

	// Clear
	if err := DB.Model(&user2).Association("Company").Clear(); err != nil {
		t.Errorf("Error happened when clear Company, got %v", err)
	}

	if err := DB.Model(&user2).Association("Manager").Clear(); err != nil {
		t.Errorf("Error happened when clear Manager, got %v", err)
	}

	AssertAssociationCount(t, user2, "Company", 0, "after clear")

    return (row == null) ? null : Maps.safeGet(row, columnKey);
  }

  @Override
  public boolean isEmpty() {
    return size() == 0;
  }

  @Override
  public void clear() {
    Iterators.clear(cellSet().iterator());
  }

  @CanIgnoreReturnValue
  @Override
  @CheckForNull
  public V remove(@CheckForNull Object rowKey, @CheckForNull Object columnKey) {

assignees: ''

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**Additional context**

    return (row == null) ? null : Maps.safeGet(row, columnKey);
  }

  @Override
  public boolean isEmpty() {
    return size() == 0;
  }

  @Override
  public void clear() {
    Iterators.clear(cellSet().iterator());
  }

  @CanIgnoreReturnValue
  @Override
  @CheckForNull
  public V remove(@CheckForNull Object rowKey, @CheckForNull Object columnKey) {

    }
  }


  public void testKeySet_clear() {
    for (LoadingCache<Object, Object> cache : caches()) {
      warmUp(cache, 0, 100);

      Set<Object> keys = cache.asMap().keySet();
      keys.clear();
      checkEmpty(keys);
      checkEmpty(cache);
    }
  }

  public void testKeySet_empty_remove() {