rkhachatryan commented on a change in pull request #16582: URL: https://github.com/apache/flink/pull/16582#discussion_r676716548
########## File path: flink-core/src/main/java/org/apache/flink/api/common/state/InternalCheckpointListener.java ########## @@ -0,0 +1,52 @@ +/* + +* 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.api.common.state; + +import org.apache.flink.annotation.Internal; + +/** + * The internal checkpoint listener add another {@link #notifyCheckpointSubsumed(long)} interface + * for internal usage. + */ +@Internal +public interface InternalCheckpointListener extends CheckpointListener { + + /** + * A invalid checkpoint id, which could be used in {@link #notifyCheckpointSubsumed(long)} to + * represent no checkpoint needs to be subsumed. + */ + long INVALID_CHECKPOINT_ID = -1; + + /** + * This method is called as a notification once a distributed checkpoint has been subsumed. + * + * <p>These notifications are "best effort", meaning they can sometimes be skipped. + * + * <p>This method is very rarely necessary to implement. The "best effort" guarantee, together + * with the fact that this method should not result in discarding any data (per the "Checkpoint + * Subsuming Contract") means it is mainly useful for earlier cleanups of auxiliary resources. + * + * @param checkpointId The ID of the checkpoint that has been subsumed. + * @throws Exception This method can propagate exceptions, which leads to a failure/recovery for + * the task or job. + */ + default void notifyCheckpointSubsumed(long checkpointId) throws Exception {} Review comment: I think having a default no-op implementation is error-prone (as it allows to forget to implement it). Do we really need it? edit: as I commented below `AbstractStreamOperatorV2` misses the implementation. -- 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. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
