wangyang0918 commented on a change in pull request #13644: URL: https://github.com/apache/flink/pull/13644#discussion_r513210810
########## File path: flink-runtime/src/main/java/org/apache/flink/runtime/leaderelection/LeaderElectionEventHandler.java ########## @@ -0,0 +1,49 @@ +/* + * 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.runtime.leaderelection; + +/** + * Interface which should be implemented to response to {@link LeaderInformation} changes in + * {@link LeaderElectionDriver}. + */ +public interface LeaderElectionEventHandler { + + /** + * Called by specific {@link LeaderElectionDriver} when the leadership is granted. + */ + void onGrantLeadership(); + + /** + * Called by specific {@link LeaderElectionDriver} when the leadership is revoked. + */ + void onRevokeLeadership(); + + /** + * Called by specific {@link LeaderElectionDriver} when the leader information is changed. Then the + * {@link DefaultLeaderElectionService} could write the leader information again if necessary. + * @param leaderInformation leader information which contains leader session id and leader address. Review comment: Yes. This method should only be called when the driver still has the leadership. I will add a description here. ---------------------------------------------------------------- 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: [email protected]
