exceptionfactory commented on code in PR #7194: URL: https://github.com/apache/nifi/pull/7194#discussion_r1198284268
########## 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 +1,155 @@ +/* + * 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.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 Sheet currentSheet; + private Iterator<Row> currentRows; + private final Map<String, Boolean> desiredSheets; + private final int firstRow; + private ComponentLog logger; + private boolean log; + private Row currentRow; + + public RowIterator(InputStream in, List<String> desiredSheets, int firstRow) { + this(in, desiredSheets, firstRow, null); + } + + public RowIterator(InputStream in, List<String> desiredSheets, int firstRow, ComponentLog logger) { + this.workbook = StreamingReader.builder() + .rowCacheSize(100) + .bufferSize(4096) + .open(in); + this.sheets = this.workbook.iterator(); + this.desiredSheets = desiredSheets != null ? desiredSheets.stream() + .collect(Collectors.toMap(key -> key, value -> Boolean.FALSE)) : new HashMap<>(); + this.firstRow = firstRow; + this.logger = logger; + this.log = logger != null; + } + + @Override + public boolean hasNext() { + setCurrent(); + boolean next = currentRow != null; + if(!next) { + String sheetsNotFound = getSheetsNotFound(desiredSheets); + if (!sheetsNotFound.isEmpty() && log) { + logger.warn("Excel sheet(s) not found: {}", sheetsNotFound); + } + } + return next; + } + + private void setCurrent() { + currentRow = getNextRow(); + if (currentRow != null) { + return; + } + + currentSheet = null; + currentRows = null; + while (sheets.hasNext()) { + currentSheet = sheets.next(); + if (isIterateOverAllSheets() || hasSheet(currentSheet.getSheetName())) { + currentRows = currentSheet.iterator(); + currentRow = getNextRow(); + if (currentRow != null) { + return; + } + } + } + } + + private Row getNextRow() { + while (currentRows != null && !hasExhaustedRows()) { + Row tempCurrentRow = currentRows.next(); + if (!isSkip(tempCurrentRow)) { + return tempCurrentRow; + } + } + return null; + } + + private boolean hasExhaustedRows() { + boolean exhausted = !currentRows.hasNext(); + if (log && exhausted) { + logger.info("Exhausted all rows from sheet {}", currentSheet.getSheetName()); + } + return exhausted; + } + + private boolean isSkip(Row row) { + return row.getRowNum() < firstRow; + } + + private boolean isIterateOverAllSheets() { + boolean iterateAllSheets = desiredSheets.isEmpty(); + if (iterateAllSheets && log) { + logger.info("Advanced to sheet {}", currentSheet.getSheetName()); + } + return iterateAllSheets; + } + + private boolean hasSheet(String name) { + boolean sheetByName = !desiredSheets.isEmpty() + && desiredSheets.keySet().stream() + .anyMatch(desiredSheet -> desiredSheet.equalsIgnoreCase(name)); + if (sheetByName) { + desiredSheets.put(name, Boolean.TRUE); + } + return sheetByName; + } + + private String getSheetsNotFound(Map<String, Boolean> desiredSheets) { + return desiredSheets.entrySet().stream() + .filter(entry -> !entry.getValue()) + .map(Map.Entry::getKey) + .collect(Collectors.joining(",")); + } + + @Override + public Row next() { + return currentRow; + } + + @Override + public void close() throws IOException { + this.workbook.close(); + } + + void setLogger(ComponentLog logger) { Review Comment: Sounds good! -- 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
