CalvinKirs commented on a change in pull request #3054: URL: https://github.com/apache/incubator-dolphinscheduler/pull/3054#discussion_r446480327
########## File path: dolphinscheduler-server/src/main/java/org/apache/dolphinscheduler/server/master/dispatch/host/assign/AbstractSelector.java ########## @@ -0,0 +1,45 @@ +/* + * 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.dolphinscheduler.server.master.dispatch.host.assign; + +import org.apache.dolphinscheduler.common.utils.CollectionUtils; + +import java.util.Collection; + +/** + * AbstractSelector + */ +public abstract class AbstractSelector<T> implements Selector<T>{ + @Override + public T select(Collection<T> source) { + + if (CollectionUtils.isEmpty(source)) { + throw new IllegalArgumentException("Empty source."); + } + + /** + * if only one , return directly + */ + if (source.size() == 1) { + return (T)source.toArray()[0]; + } + return doSelect(source); + } + + protected abstract T doSelect(Collection<T> source); + +} Review comment: Thank you very much for your review, but I personally are not very inclined to implement the default method of the interface. The original intention of the default method is to add new functions to the smooth evolution of the existing interface. It is not very appropriate to put it here. what do you think? ---------------------------------------------------------------- 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]
