exceptionfactory commented on code in PR #7194: URL: https://github.com/apache/nifi/pull/7194#discussion_r1218506840
########## nifi-nar-bundles/nifi-standard-services/nifi-record-serialization-services-bundle/nifi-record-serialization-services/src/main/java/org/apache/nifi/excel/RowIterator.java: ########## @@ -0,0 +1,147 @@ +/* + * 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.nifi.excel; + +import com.github.pjfanning.xlsx.StreamingReader; +import org.apache.nifi.logging.ComponentLog; +import org.apache.nifi.processor.exception.ProcessException; +import org.apache.poi.ss.usermodel.Row; +import org.apache.poi.ss.usermodel.Sheet; +import org.apache.poi.ss.usermodel.Workbook; + +import java.io.Closeable; +import java.io.IOException; +import java.io.InputStream; +import java.util.HashMap; +import java.util.Iterator; +import java.util.List; +import java.util.Map; +import java.util.stream.Collectors; + +public class RowIterator implements Iterator<Row>, Closeable { + private final Workbook workbook; + private final Iterator<Sheet> sheets; + private final Map<String, Boolean> requiredSheets; + private final int firstRow; + private final ComponentLog logger; + private Sheet currentSheet; + private Iterator<Row> currentRows; + private Row currentRow; + + public RowIterator(InputStream in, List<String> requiredSheets, int firstRow, ComponentLog logger) { + this.workbook = StreamingReader.builder() + .rowCacheSize(100) + .bufferSize(4096) + .open(in); + this.sheets = this.workbook.iterator(); + this.requiredSheets = requiredSheets != null ? requiredSheets.stream() + .collect(Collectors.toMap(key -> key, value -> Boolean.FALSE)) : new HashMap<>(); + this.firstRow = firstRow; + this.logger = logger; + } + + @Override + public boolean hasNext() { + setCurrent(); Review Comment: It should be possible to call `hasNext()` in any order. Taking a closer look, it seems like the current implementation of `setCurrent` needs further refinement because it sets `currentSheet` to `null` on every invocation. One general approach could be to set the initial sheet and row in the constructor. In general, it should be possible to call `hasNext()` and unlimited number of times without advancing the iterator, and it calling `next()` should advance the iterator forward. When all sheets and rows have been read, `next()` should throw an `IllegalStateException` if called again. -- 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...@nifi.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
