| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| package org.apache.sling.distribution.queue; |
| |
| import javax.annotation.CheckForNull; |
| import javax.annotation.Nonnull; |
| import javax.annotation.Nullable; |
| |
| import aQute.bnd.annotation.ProviderType; |
| |
| /** |
| * A queue is responsible for collecting the {@link org.apache.sling.distribution.packaging.DistributionPackage}s |
| * exported by a {@link org.apache.sling.distribution.agent.DistributionAgent} in |
| * order to be able to process them also when there are multiple (concurrent) |
| * {@link org.apache.sling.distribution.communication.DistributionRequest}s executed |
| * on that same agent. |
| * <p/> |
| * The items (packages) in the queue can then get processed according to a FIFO |
| * strategy or in parallel, or some other way, via {@link org.apache.sling.distribution.queue.DistributionQueueProcessor}s. |
| */ |
| @ProviderType |
| public interface DistributionQueue { |
| |
| /** |
| * get this queue name |
| * |
| * @return the queue name |
| */ |
| @Nonnull |
| String getName(); |
| |
| /** |
| * add a distribution item to this queue |
| * |
| * @param item a distribution item representing a {@link org.apache.sling.distribution.packaging.DistributionPackage} |
| * to distribute |
| * @return {@code true} if the distribution item was added correctly to the queue, |
| * {@code false} otherwise |
| */ |
| boolean add(@Nonnull DistributionQueueItem item); |
| |
| /** |
| * get the status of a certain item in the queue |
| * |
| * @param item the distribution item to get the status for |
| * @return the item status in the queue |
| * @throws DistributionQueueException if any error occurs while getting the status |
| */ |
| @Nonnull |
| DistributionQueueItemStatus getStatus(@Nonnull DistributionQueueItem item) |
| throws DistributionQueueException; |
| |
| /** |
| * get the first item (in a FIFO strategy, the next to be processed) from the queue |
| * |
| * @return the first item into the queue or {@code null} if the queue is empty |
| */ |
| @CheckForNull |
| DistributionQueueItem getHead(); |
| |
| /** |
| * check if the queue is empty |
| * |
| * @return {@code true} if the queue is empty, {@code false} otherwise |
| */ |
| boolean isEmpty(); |
| |
| /** |
| * get all the items in the queue |
| * |
| * @param skip the number of items to skip |
| * @param limit the maximum number of items to return. use -1 to return all items. |
| * @return a {@link java.lang.Iterable} of {@link DistributionQueueItem}s |
| */ |
| @Nonnull |
| Iterable<DistributionQueueItem> getItems(int skip, int limit); |
| |
| /** |
| * remove an item from the queue by specifying its id |
| * |
| * @param packageId the id of the package represented by the item |
| * @return the removed item, or {@code null} if the item with the given id |
| * doesn't exist |
| */ |
| DistributionQueueItem remove(@Nonnull String packageId); |
| } |