StefanRRichter commented on a change in pull request #8431: [FLINK-12480] Introduce mailbox to StreamTask main-loop URL: https://github.com/apache/flink/pull/8431#discussion_r283897469
########## File path: flink-streaming-java/src/main/java/org/apache/flink/streaming/runtime/tasks/mailbox/Mailbox.java ########## @@ -0,0 +1,36 @@ +/* + * 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.flink.streaming.runtime.tasks.mailbox; + +import javax.annotation.Nonnull; + +/** + * A mailbox is basically a blocking queue for inter-thread message exchange in form of {@link Runnable} objects between + * multiple producer threads and a single consumer. + */ +public interface Mailbox extends MailboxReceiver, MailboxSender { Review comment: Necessary is relative because the default is IMO `@Internal`. Furthermore, `MailboxSender` might eventually become publicly exposed for user code to schedule tasks into the task's main thread, e.g. through the context of source functions, similar to the checkpoint lock to enable atomic operations. I would then mark it accordingly later, when it is exposed. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services
