zhipeng93 commented on a change in pull request #29: URL: https://github.com/apache/flink-ml/pull/29#discussion_r746279810
########## File path: flink-ml-lib/src/main/java/org/apache/flink/ml/operator/batch/BatchOperator.java ########## @@ -0,0 +1,109 @@ +/* + * 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.ml.operator.batch; + +import org.apache.flink.ml.operator.BaseAlgoImpl; +import org.apache.flink.ml.param.Param; +import org.apache.flink.table.api.Table; + +import java.util.Arrays; +import java.util.Map; + +/** + * Base class of offline learning algorithm operators. + * + * <p>This class extends {@link BaseAlgoImpl} to support data transmission between BatchOperators. + */ +public abstract class BatchOperator<T extends BatchOperator<T>> extends BaseAlgoImpl<T> { Review comment: Hi Dong, thanks for the review :) As proposed in the [FLIP-173](https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=184615783), we support Transformer/Estimator/AlgoOperator with multiple inputs and multiple outputs. Though there exist s transformers/estimators/algoOperators that accept multiple inputs and output, the real case is that many of them still have single input and single output (e.g., Logsitic Regression, K-Means, K-NN, etc). Thus to increase the usability, we would like to distinguish the main output and sideoutputs here. A motivation example can be found [here](https://docs.google.com/document/d/1L3aI9LjkcUPoM52liEY6uFktMnFMNFQ6kXAjnz_11do/edit#heading=h.58nok892sbom). -- 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: issues-unsubscr...@flink.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
