本文整理了Java中org.apache.commons.collections4.CollectionUtils.emptyIfNull()方法的一些代码示例，展示了CollectionUtils.emptyIfNull()的具体用法。这些代码示例主要来源于Github/Stackoverflow/Maven等平台，是从一些精选项目中提取出来的代码，具有较强的参考意义，能在一定程度帮忙到你。CollectionUtils.emptyIfNull()方法的具体详情如下：
包路径：org.apache.commons.collections4.CollectionUtils
类名称：CollectionUtils
方法名：emptyIfNull

CollectionUtils.emptyIfNull介绍

[英]Returns an immutable empty collection if the argument is null, or the argument itself otherwise.
[中]如果参数为null，则返回不可变的空集合，否则返回参数本身。

代码示例

代码示例来源：origin: org.apache.commons/commons-collections4

/**
 * Removes all values associated with the specified key.
 * <p>
 * A subsequent <code>get(Object)</code> would return an empty collection.
 *
 * @param key  the key to remove values from
 * @return the <code>Collection</code> of values removed, will return an
 *   empty, unmodifiable collection for no mapping found
 */
@Override
public Collection<V> remove(final Object key) {
  return CollectionUtils.emptyIfNull(getMap().remove(key));
}

代码示例来源：origin: BroadleafCommerce/BroadleafCommerce

@Override
public Integer calculateNumShippableFulfillmentGroups(Order order) {
  Integer numShippableFulfillmentGroups = 0;
  List<FulfillmentGroup> fulfillmentGroups = order.getFulfillmentGroups();
  for (FulfillmentGroup fulfillmentGroup : CollectionUtils.emptyIfNull(fulfillmentGroups)) {
    if (isShippable(fulfillmentGroup.getType())) {
      numShippableFulfillmentGroups++;
    }
  }
  return numShippableFulfillmentGroups;
}

代码示例来源：origin: BroadleafCommerce/BroadleafCommerce

@Override
public boolean cartHasCreditCardPayment() {
  Order cart = CartState.getCart();
  List<OrderPayment> orderPayments = orderPaymentService.readPaymentsForOrder(cart);
  for (OrderPayment payment : CollectionUtils.emptyIfNull(orderPayments))  {
    boolean isCreditCartPayment = PaymentType.CREDIT_CARD.equals(payment.getType());
    if (payment.isActive() && isCreditCartPayment) {
      return true;
    }
  }
  return false;
}

代码示例来源：origin: BroadleafCommerce/BroadleafCommerce

@Override
public boolean cartHasThirdPartyPayment() {
  Order cart = CartState.getCart();
  List<OrderPayment> orderPayments = orderPaymentService.readPaymentsForOrder(cart);
  for (OrderPayment payment : CollectionUtils.emptyIfNull(orderPayments))  {
    if (payment.isActive() && PaymentType.THIRD_PARTY_ACCOUNT.equals(payment.getType())) {
      return true;
    }
  }
  return false;
}

代码示例来源：origin: BroadleafCommerce/BroadleafCommerce

protected Address getAddressFromCCOrderPayment(Order cart) {
  List<OrderPayment> orderPayments = orderPaymentService.readPaymentsForOrder(cart);
  for (OrderPayment payment : CollectionUtils.emptyIfNull(orderPayments)) {
    boolean isCreditCardPaymentType = PaymentType.CREDIT_CARD.equals(payment.getType());
    boolean paymentHasBillingAddress = (payment.getBillingAddress() != null);
    if (payment.isActive() && isCreditCardPaymentType && paymentHasBillingAddress) {
      return payment.getBillingAddress();
    }
  }
  return null;
}

代码示例来源：origin: BroadleafCommerce/BroadleafCommerce

@Override
public boolean cartHasPopulatedShippingAddress() {
  Order cart = CartState.getCart();
  for (FulfillmentGroup fulfillmentGroup : CollectionUtils.emptyIfNull(cart.getFulfillmentGroups())) {
    if (fulfillmentGroupService.isShippable(fulfillmentGroup.getType())) {
      if (fulfillmentGroup.getAddress() != null && fulfillmentGroup.getFulfillmentOption() != null) {
        return true;
      }
    }
  }
  return false;
}

代码示例来源：origin: BroadleafCommerce/BroadleafCommerce

@Override
public boolean cartHasPopulatedBillingAddress() {
  Order cart = CartState.getCart();
  List<OrderPayment> orderPayments = orderPaymentService.readPaymentsForOrder(cart);
  for (OrderPayment payment : CollectionUtils.emptyIfNull(orderPayments)) {
    boolean isCreditCardPayment = PaymentType.CREDIT_CARD.equals(payment.getType());
    boolean paymentHasBillingAddress = (payment.getBillingAddress() != null);
    if (payment.isActive() && isCreditCardPayment && paymentHasBillingAddress) {
      return true;
    }
  }
  return false;
}

代码示例来源：origin: BroadleafCommerce/BroadleafCommerce

@Override
public boolean cartHasTemporaryCreditCard() {
  Order cart = CartState.getCart();
  List<OrderPayment> orderPayments = orderPaymentService.readPaymentsForOrder(cart);
  for (OrderPayment payment : CollectionUtils.emptyIfNull(orderPayments))  {
    boolean isCreditCartPayment = PaymentType.CREDIT_CARD.equals(payment.getType());
    boolean isTemporaryPaymentGateway = PaymentGatewayType.TEMPORARY.equals(payment.getGatewayType());
    if (payment.isActive() && isCreditCartPayment && isTemporaryPaymentGateway) {
      return true;
    }
  }
  return false;
}

代码示例来源：origin: BroadleafCommerce/BroadleafCommerce

protected OrderPayment getUnconfirmedCCFromCart() {
  OrderPayment unconfirmedCC = null;
  Order cart = CartState.getCart();
  List<OrderPayment> orderPayments = orderPaymentService.readPaymentsForOrder(cart);
  for (OrderPayment payment : CollectionUtils.emptyIfNull(orderPayments))  {
    boolean isCreditCartPayment = PaymentType.CREDIT_CARD.equals(payment.getType());
    boolean isTemporaryPaymentGateway = PaymentGatewayType.TEMPORARY.equals(payment.getGatewayType());
    if (payment.isActive() && isCreditCartPayment && !isTemporaryPaymentGateway) {
      unconfirmedCC = payment;
    }
  }
  return unconfirmedCC;
}

代码示例来源：origin: Evolveum/midpoint

public void setOrdering(Collection<? extends ObjectOrdering> orderings) {
  this.ordering.clear();
  for (ObjectOrdering ordering : CollectionUtils.emptyIfNull(orderings)) {
    this.ordering.add((ObjectOrderingImpl) ordering);
  }
}

代码示例来源：origin: Evolveum/midpoint

public void setGrouping(Collection<ObjectGrouping> groupings) {
  this.grouping.clear();
  for (ObjectGrouping grouping : CollectionUtils.emptyIfNull(groupings)) {
    this.grouping.add((ObjectGroupingImpl) grouping);
  }
}

代码示例来源：origin: DSpace/DSpace

public DiscoverySearchFilter getSearchFilter(String name) {
  for (DiscoverySearchFilter filter : CollectionUtils.emptyIfNull(searchFilters)) {
    if (StringUtils.equals(name, filter.getIndexFieldName())) {
      return filter;
    }
  }
  return null;
}

代码示例来源：origin: org.ligoj.bootstrap/bootstrap-web

@Override
  protected Set<String> findConnectionHeaders(final HttpServletRequest clientRequest) {
    final Set<String> ignoreRequestHeader = new HashSet<>();
    ignoreRequestHeader.addAll(CollectionUtils.emptyIfNull(super.findConnectionHeaders(clientRequest)));

    // Drop cookie headers forward from FRONT to BACK by default, only filtered ones will be added
    ignoreRequestHeader.add(HEADER_COOKIE);
    return ignoreRequestHeader;
  }
}

代码示例来源：origin: org.ligoj.plugin/plugin-id

/**
   * Convert the given user UIDs to a the corresponding DN. The users must exists.
   * 
   * @param uids
   *            The UIDs to convert.
   * @return The corresponding DN.
   */
  private List<String> toDn(final List<String> uids) {
    return CollectionUtils.emptyIfNull(uids).stream().map(getUser()::findByIdExpected).map(UserOrg::getDn)
        .collect(Collectors.toList());
  }
}

代码示例来源：origin: Evolveum/midpoint

void trimItemsDefinitionsTrees(Collection<? extends ItemPath> alwaysKeep) {
  // to play safe, we won't touch PCV-specific complexTypeDefinition
  for (Item<?, ?> item : CollectionUtils.emptyIfNull(items)) {
    if (item instanceof PrismContainer) {
      Collection<ItemPath> alwaysKeepInSub = ItemPathCollectionsUtil.remainder(CollectionUtils.emptyIfNull(alwaysKeep),
          item.getElementName(), false);
      ((PrismContainer<?>) item).trimDefinitionTree(alwaysKeepInSub);
    }
  }
}

代码示例来源：origin: Evolveum/midpoint

@NotNull
  private List<? extends ItemPath> getPathsToResolve(Collection<SelectorOptions<GetOperationOptions>> options) {
    final UniformItemPath EMPTY_PATH = prismContext.emptyPath();
    List<UniformItemPath> rv = new ArrayList<>();
    for (SelectorOptions<GetOperationOptions> option : CollectionUtils.emptyIfNull(options)) {
      if (GetOperationOptions.isResolveNames(option.getOptions())) {
        rv.add(option.getItemPath(EMPTY_PATH));
      }
    }
    return rv;
  }
}

代码示例来源：origin: Evolveum/midpoint

public static void displayObjectTypeCollection(String message, Collection<? extends ObjectType> collection) {
  System.out.println(OBJECT_TITLE_OUT_PREFIX + message);
  LOGGER.debug(OBJECT_TITLE_LOG_PREFIX + message);
  for (ObjectType o : CollectionUtils.emptyIfNull(collection)) {
    System.out.println(ObjectTypeUtil.dump(o));
    LOGGER.debug(ObjectTypeUtil.dump(o));
    System.out.println(OBJECT_LIST_SEPARATOR);
    LOGGER.debug(OBJECT_LIST_SEPARATOR);
  }
}

代码示例来源：origin: Evolveum/midpoint

private <T> void assertUnsortedListsEquals(String message, Collection<String> expected, Collection<T> real, Function<T, String> nameExtractor) {
  Bag<String> expectedAsBag = new TreeBag<>(CollectionUtils.emptyIfNull(expected));
  Bag<String> realAsBag = new TreeBag<>(real.stream().map(nameExtractor).collect(Collectors.toList()));
  assertEquals(message, expectedAsBag, realAsBag);
}

代码示例来源：origin: Evolveum/midpoint

private void assertTargetPolicyRules(EvaluatedAssignmentImpl<? extends FocusType> evaluatedAssignment,
    Collection<String> expectedThisTargetItems, Collection<String> expectedOtherTargetsItems) {
  expectedOtherTargetsItems = CollectionUtils.emptyIfNull(expectedOtherTargetsItems);
  expectedThisTargetItems = CollectionUtils.emptyIfNull(expectedThisTargetItems);
  assertUnsortedListsEquals("Wrong other targets policy rules", expectedOtherTargetsItems,
      evaluatedAssignment.getOtherTargetsPolicyRules(), r -> r.getName());
  assertUnsortedListsEquals("Wrong this target policy rules", expectedThisTargetItems,
      evaluatedAssignment.getThisTargetPolicyRules(), r -> r.getName());
}

代码示例来源：origin: Evolveum/midpoint

private <AH extends AssignmentHolderType> boolean pathMatches(ObjectDelta<?> delta, PrismObject<AH> objectOld, ItemPath path,
    boolean exactPathMatch) throws SchemaException {
  if (delta.isAdd()) {
    return delta.getObjectToAdd().containsItem(path, false);
  } else if (delta.isDelete()) {
    return objectOld != null && objectOld.containsItem(path, false);
  } else {
    return ItemDeltaCollectionsUtil.pathMatches(emptyIfNull(delta.getModifications()), path, 0, exactPathMatch);
  }
}