Apache POI SAX XSSFReader 读取错误的日期格式

Question

Apache POI SAX reader 实现类似于这个众所周知的示例 https://github.com/pjfanning/poi-shared-strings-sample/blob/master/src/main/java/com/github/pjfanning/poi/sample/XLSX2CSV.java 读取一些日期值，而不是它们在 excel 中显示的日期值，尽管它应该读取 "formatted value".

excel 文件中的值：1/1/2019，"formatted value" 由 reader 读取：1/ 1/19.

知道为什么会有差异吗？

Apache POI 版本 3.17

Reader代码：

package com.lopuch.sk.lita.is.importer;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.HashMap;
import java.util.Map;

import javax.xml.parsers.ParserConfigurationException;

import org.apache.log4j.Logger;
import org.apache.poi.openxml4j.exceptions.OpenXML4JException;
import org.apache.poi.openxml4j.opc.OPCPackage;
import org.apache.poi.openxml4j.util.ZipSecureFile;
import org.apache.poi.ss.usermodel.DataFormatter;
import org.apache.poi.ss.util.CellAddress;
import org.apache.poi.ss.util.CellReference;
import org.apache.poi.util.SAXHelper;
import org.apache.poi.xssf.eventusermodel.ReadOnlySharedStringsTable;
import org.apache.poi.xssf.eventusermodel.XSSFReader;
import org.apache.poi.xssf.eventusermodel.XSSFSheetXMLHandler;
import org.apache.poi.xssf.eventusermodel.XSSFSheetXMLHandler.SheetContentsHandler;
import org.apache.poi.xssf.model.StylesTable;
import org.apache.poi.xssf.usermodel.XSSFComment;
import org.xml.sax.ContentHandler;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;

import com.lopuch.sk.lita.is.importer.fileImport.ExcelRowReadListener;

public class ExcelSaxImporter {

    private static final Logger logger = Logger.getLogger(ExcelSaxImporter.class);

    private ExcelRowReadListener listener;

    public void setOnRowRead(ExcelRowReadListener listener) {
        this.listener = listener;
    }

    public ExcelRowReadListener getListener() {
        return listener;
    };

    public void process(byte[] fileByteArray)
            throws IOException, OpenXML4JException, ParserConfigurationException, SAXException {
        ZipSecureFile.setMinInflateRatio(0.0d);
        OPCPackage opcpPackage = OPCPackage.open(new ByteArrayInputStream(fileByteArray));
        ReadOnlySharedStringsTable strings = new ReadOnlySharedStringsTable(opcpPackage);
        XSSFReader xssfReader = new XSSFReader(opcpPackage);
        StylesTable styles = xssfReader.getStylesTable();
        XSSFReader.SheetIterator iter = (XSSFReader.SheetIterator) xssfReader.getSheetsData();

        while (iter.hasNext()) {
            InputStream stream = iter.next();
            processSheet(styles, strings, getHandler(), stream);
            stream.close();
        }
    }

    private SheetContentsHandler getHandler() {
        return new SheetContentsHandler() {

            private boolean firstCellOfRow = false;
            private int currentRow = -1;
            private int currentCol = -1;

            // Maps column Letter name to its value.
            // Does not contain key-value pair if cell value is null for
            // currently
            // processed column and row.
            private Map<String, String> rowValues;

            @Override
            public void startRow(int rowNum) {
                // Prepare for this row
                firstCellOfRow = true;
                currentRow = rowNum;
                currentCol = -1;
                rowValues = new HashMap<String, String>();
            }

            @Override
            public void endRow(int rowNum) {
                if (rowValues.keySet().size() == 0) {
                    logger.trace("Skipping calling rowRead() because of empty row");
                } else {
                    ExcelSaxImporter.this.getListener().rowRead(rowValues);
                }
            }

            @Override
            public void cell(String cellReference, String formattedValue, XSSFComment comment) {
                if (firstCellOfRow) {
                    firstCellOfRow = false;
                }

                // gracefully handle missing CellRef here in a similar way
                // as XSSFCell does
                if (cellReference == null) {
                    cellReference = new CellAddress(currentRow, currentCol).formatAsString();
                }

                // Did we miss any cells?
                int thisCol = (new CellReference(cellReference)).getCol();
                currentCol = thisCol;

                cellReference = cellReference.replaceAll("\d","");
                rowValues.put(cellReference, formattedValue);

            }

            @Override
            public void headerFooter(String text, boolean isHeader, String tagName) {
            }
        };
    }

    /**
     * Parses and shows the content of one sheet using the specified styles and
     * shared-strings tables.
     *
     * @param styles
     * @param strings
     * @param sheetInputStream
     */
    public void processSheet(StylesTable styles, ReadOnlySharedStringsTable strings, SheetContentsHandler sheetHandler,
            InputStream sheetInputStream) throws IOException, ParserConfigurationException, SAXException {
        DataFormatter formatter = new DataFormatter();
        InputSource sheetSource = new InputSource(sheetInputStream);
        try {
            XMLReader sheetParser = SAXHelper.newXMLReader();
            ContentHandler handler = new XSSFSheetXMLHandler(styles, null, strings, sheetHandler, formatter, false);
            sheetParser.setContentHandler(handler);
            sheetParser.parse(sheetSource);
        } catch (ParserConfigurationException e) {
            throw new RuntimeException("SAX parser appears to be broken - " + e.getMessage());
        }
    }
}

Answer 1

excel 显示的值与 Apache POI 读取的值的差异来自对用户语言设置作出反应的日期格式。来自 Excel:

Date formats that begin with an asterisk (*) responds to changes in regional date and time settings that are specified for the operating system.

Apache POI DataFormatter 忽略这些特定于语言环境的格式和 returns 默认美国格式日期。来自 Apache POI DataFormatter 文档：

Some formats are automatically "localized" by Excel, eg show as mm/dd/yyyy when loaded in Excel in some Locales but as dd/mm/yyyy in others. These are always returned in the "default" (US) format, as stored in the file.

要解决此问题，请参阅对

的回答

Apache POI SAX XSSFReader 读取错误的日期格式

Apache POI SAX XSSFReader reads wrong date format

java

excel

saxparser

apache-poi

xssf