| /* |
| * Copyright (c) OSGi Alliance (2015, 2016). All Rights Reserved. |
| * |
| * Licensed 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.osgi.util.pushstream; |
| |
| import org.osgi.annotation.versioning.ConsumerType; |
| |
| /** |
| * An event source. An event source can open a channel between a source and a |
| * consumer. Once the channel is opened (even before it returns) the source can |
| * send events to the consumer. |
| * |
| * A source should stop sending and automatically close the channel when sending |
| * an event returns a negative value, see {@link PushEventConsumer#ABORT}. |
| * Values that are larger than 0 should be treated as a request to delay the |
| * next events with those number of milliseconds. |
| * |
| * @param <T> |
| * The payload type |
| */ |
| @ConsumerType |
| @FunctionalInterface |
| public interface PushEventSource<T> { |
| |
| /** |
| * Open the asynchronous channel between the source and the consumer. The |
| * call returns an {@link AutoCloseable}. This can be closed, and should |
| * close the channel, including sending a Close event if the channel was not |
| * already closed. The returned object must be able to be closed multiple |
| * times without sending more than one Close events. |
| * |
| * @param aec the consumer (not null) |
| * @return a {@link AutoCloseable} that can be used to close the stream |
| * @throws Exception |
| */ |
| AutoCloseable open(PushEventConsumer< ? super T> aec) throws Exception; |
| } |