JingsongLi commented on code in PR #104: URL: https://github.com/apache/flink-table-store/pull/104#discussion_r912611645
########## flink-table-store-core/src/main/java/org/apache/flink/table/store/file/mergetree/compact/MergeFunctionHelper.java: ########## @@ -0,0 +1,73 @@ +/* + * 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.table.store.file.mergetree.compact; + +import org.apache.flink.table.data.GenericRowData; +import org.apache.flink.table.data.RowData; + +import static org.apache.flink.table.store.file.mergetree.compact.ValueCountMergeFunction.count; + +/** Helper functions for the interaction with {@link MergeFunction}. */ +public class MergeFunctionHelper { + + private final MergeFunction mergeFunction; + + private RowData rowData; + private boolean isInitialized; + + public MergeFunctionHelper(MergeFunction mergeFunction) { + this.mergeFunction = mergeFunction; + } + + /** + * Resets the {@link MergeFunction} helper to its default state: 1. Clears the one record which + * the helper maintains. 2. Resets the {@link MergeFunction} to its default state. 3. Clears the + * initialized state of the {@link MergeFunction}. + */ + public void reset() { + rowData = null; + mergeFunction.reset(); + isInitialized = false; + } + + /** Adds the given {@link RowData} to the {@link MergeFunction} helper. */ + public void add(RowData value) { + if (rowData == null) { + rowData = value; + } else { + if (!isInitialized) { + mergeFunction.add(rowData); + isInitialized = true; + } + mergeFunction.add(value); + } + } + + /** + * Get current value of the {@link MergeFunction} helper. Return null if the value should be + * skipped. + */ + public RowData getValue() { + return isInitialized + ? mergeFunction.getValue() + : mergeFunction instanceof ValueCountMergeFunction Review Comment: Just `rowData`? The input of `ValueCountMergeFunction` should not be count zero. -- 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]
