XLSXCovertCSVReader 工具类（XML ）

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import cn.com.amway.msgcenter.console.util.StringUtil;
import org.apache.poi.hssf.usermodel.HSSFDateUtil;
import org.apache.poi.openxml4j.exceptions.OpenXML4JException;
import org.apache.poi.openxml4j.opc.OPCPackage;
import org.apache.poi.openxml4j.opc.PackageAccess;
import org.apache.poi.ss.usermodel.BuiltinFormats;
import org.apache.poi.ss.usermodel.DataFormatter;
import org.apache.poi.xssf.eventusermodel.ReadOnlySharedStringsTable;
import org.apache.poi.xssf.eventusermodel.XSSFReader;
import org.apache.poi.xssf.model.StylesTable;
import org.apache.poi.xssf.usermodel.XSSFCellStyle;
import org.apache.poi.xssf.usermodel.XSSFRichTextString;
import org.xml.sax.Attributes;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.DefaultHandler;

import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintStream;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

/**

  • 使用CVS模式解决XLSX文件，可以有效解决用户模式内存溢出的问题 该模式是POI官方推荐的读取大数据的模式，在用户模式下，数据量较大、Sheet较多、或者是有很多无用的空行的情况
  • ，容易出现内存溢出,用户模式读取Excel的典型代码如下： FileInputStream file=new FileInputStream("c: est.xlsx"); Workbook
  • wb=new XSSFWorkbook(file);

  • @author 山人
    */
    public class XLSXCovertCSVReader {

    /**

    • The type of the data value is indicated by an attribute on the cell. The value is usually in
    • a "v" element within the cell.
      */
      enum xssfDataType {
      BOOL, ERROR, FORMULA, INLINESTR, SSTINDEX, NUMBER,
      }

    /**

    • 使用xssf_sax_API处理Excel,请参考： http://poi.apache.org/spreadsheet/how-to.html#xssf_sax_api
    • <p/>
    • Also see Standard ECMA-376, 1st edition, part 4, pages 1928ff, at
    • http://www.ecma-international.org/publications/standards/Ecma-376.htm
    • <p/>

    • A web-friendly version is http://openiso.org/Ecma/376/Part4
      */
      class MyXSSFSheetHandler extends DefaultHandler {

      /**

      • Table with styles
        */
        private StylesTable stylesTable;

      /**

      • Table with unique strings
        */
        private ReadOnlySharedStringsTable sharedStringsTable;

      /**

      • Destination for data
        */
        private final PrintStream output;

      /**

      • Number of columns to read starting with leftmost
        */
        private final int minColumnCount;

      // Set when V start element is seen
      private boolean vIsOpen;

      // Set when cell start element is seen;
      // used when cell close element is seen.
      private xssfDataType nextDataType;

      // Used to format numeric cell values.
      private short formatIndex;
      private String formatString;
      private final DataFormatter formatter;

      private int thisColumn = -1;
      // The last column printed to the output stream
      private int lastColumnNumber = -1;

      // Gathers characters as they are seen.
      private StringBuffer value;
      private String[] record;
      private List<String[]> rows = new ArrayList<String[]>();
      private boolean isCellNull = false;

      /**

      • Accepts objects needed while parsing.
      • @param styles Table of styles
      • @param strings Table of shared strings
      • @param cols Minimum number of columns to show
      • @param target Sink for output
        */
        public MyXSSFSheetHandler(StylesTable styles, ReadOnlySharedStringsTable strings, int cols, PrintStream target) {
        this.stylesTable = styles;
        this.sharedStringsTable = strings;
        this.minColumnCount = cols;
        this.output = target;
        this.value = new StringBuffer();
        this.nextDataType = xssfDataType.NUMBER;
        this.formatter = new DataFormatter();
        record = new String[this.minColumnCount];
        rows.clear();// 每次读取都清空行集合
        }

      /*

      • (non-Javadoc)
      • @see org.xml.sax.helpers.DefaultHandler#startElement(java.lang.String, java.lang.String,

      • java.lang.String, org.xml.sax.Attributes)
        */
        public void startElement(String uri, String localName, String name, Attributes attributes) throws SAXException {

        if ("inlineStr".equals(name) || "v".equals(name)) {
        vIsOpen = true;
        // Clear contents cache
        value.setLength(0);
        }
        // c => cell
        else if ("c".equals(name)) {
        // Get the cell reference
        String r = attributes.getValue("r");
        int firstDigit = -1;
        for (int c = 0; c < r.length(); ++c) {
        if (Character.isDigit(r.charAt(c))) {
        firstDigit = c;
        break;
        }
        }
        thisColumn = nameToColumn(r.substring(0, firstDigit));

        // Set up defaults.
this.nextDataType = xssfDataType.NUMBER;
this.formatIndex = -1;
this.formatString = null;
String cellType = attributes.getValue("t");
String cellStyleStr = attributes.getValue("s");
if ("b".equals(cellType))
    nextDataType = xssfDataType.BOOL;
else if ("e".equals(cellType))
    nextDataType = xssfDataType.ERROR;
else if ("inlineStr".equals(cellType))
    nextDataType = xssfDataType.INLINESTR;
else if ("s".equals(cellType))
    nextDataType = xssfDataType.SSTINDEX;
else if ("str".equals(cellType))
    nextDataType = xssfDataType.FORMULA;
else if (cellStyleStr != null) {
    // It‘s a number, but almost certainly one
    // with a special style or format
    int styleIndex = Integer.parseInt(cellStyleStr);
    XSSFCellStyle style = stylesTable.getStyleAt(styleIndex);
    this.formatIndex = style.getDataFormat();
    this.formatString = style.getDataFormatString();
    if (this.formatString == null)
        this.formatString = BuiltinFormats.getBuiltinFormat(this.formatIndex);
}

        }

      }

      /*

      • (non-Javadoc)
      • @see org.xml.sax.helpers.DefaultHandler#endElement(java.lang.String, java.lang.String,

      • java.lang.String)
        */
        public void endElement(String uri, String localName, String name) throws SAXException {

        String thisStr = null;

        // v => contents of a cell
        if ("v".equals(name)) {
        // Process the value contents as required.
        // Do now, as characters() may be called more than once
        switch (nextDataType) {

            case BOOL:
        char first = value.charAt(0);
        thisStr = first == ‘0‘ ? "FALSE" : "TRUE";
        break;

    case ERROR:
        thisStr = ""ERROR:" + value.toString() + ‘"‘;
        break;

    case FORMULA:
        // A formula could result in a string value,
        // so always add double-quote characters.
        thisStr = value.toString();
        break;

    case INLINESTR:
        // TODO: have seen an example of this, so it‘s untested.
        XSSFRichTextString rtsi = new XSSFRichTextString(value.toString());
        thisStr = rtsi.toString();
        break;

    case SSTINDEX:
        String sstIndex = value.toString();
        try {
            int idx = Integer.parseInt(sstIndex);
            XSSFRichTextString rtss = new XSSFRichTextString(sharedStringsTable.getEntryAt(idx));
            thisStr = rtss.toString();
        } catch (NumberFormatException ex) {
            output.println("Failed to parse SST index ‘" + sstIndex + "‘: " + ex.toString());
        }
        break;

    case NUMBER:
        String n = value.toString();
        // 判断是否是日期格式
        if (HSSFDateUtil.isADateFormat(this.formatIndex, n)) {
            Double d = Double.parseDouble(n);
            Date date = HSSFDateUtil.getJavaDate(d);
            thisStr = formateDateToString(date);
        } else if (this.formatString != null)
            thisStr =
                    formatter.formatRawCellContents(Double.parseDouble(n), this.formatIndex,
                            this.formatString);
        else
            thisStr = n;
        break;

    default:
        thisStr = "(TODO: Unexpected type: " + nextDataType + ")";
        break;
}

// Output after we‘ve seen the string contents
// Emit commas for any fields that were missing on this row
if (lastColumnNumber == -1) {
    lastColumnNumber = 0;
}
// 判断单元格的值是否为空
if (thisStr == null || "".equals(isCellNull)) {
    isCellNull = true;// 设置单元格是否为空值
}
record[thisColumn] = thisStr;
// Update column
if (thisColumn > -1) lastColumnNumber = thisColumn;

        } else if ("row".equals(name)) {

        // Print out any missing commas if needed
if (minColumns > 0) {
    // Columns are 0 based
    if (lastColumnNumber == -1) {
        lastColumnNumber = 0;
    }
    if (isCellNull == false)// 判断是否空行
    {
        rows.add(record.clone());
        isCellNull = false;
        for (int i = 0; i < record.length; i++) {
            record[i] = null;
        }
    }
}
lastColumnNumber = -1;

        }

      }

      public List<String[]> getRows() {
      return rows;
      }

      public void setRows(List<String[]> rows) {
      this.rows = rows;
      }

      /**

      • Captures characters only if a suitable element is open. Originally was just "v"; extended
      • for inlineStr also.
        */
        public void characters(char[] ch, int start, int length) throws SAXException {
        if (vIsOpen) value.append(ch, start, length);
        }

      /**

      • Converts an Excel column name like "C" to a zero-based index.
      • @param name
      • @return Index corresponding to the specified name
        /
        private int nameToColumn(String name) {
        int column = -1;
        for (int i = 0; i < name.length(); ++i) {
        int c = name.charAt(i);
        column = (column + 1)         26 + c - ‘A‘;
        }
        return column;
        }

      private String formateDateToString(Date date) {
      SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");// 格式化日期
      return sdf.format(date);

      }

    }

    // /////////////////////////////////////

    private OPCPackage xlsxPackage;
    private int minColumns;
    private PrintStream output;

    /**

    • Creates a new XLSX -> CSV converter
    • @param pkg The XLSX package to process
    • @param output The PrintStream to output the CSV to
    • @param minColumns The minimum number of columns to output, or -1 for no minimum
      */
      public XLSXCovertCSVReader(OPCPackage pkg, PrintStream output, int minColumns) {
      this.xlsxPackage = pkg;
      this.output = output;
      this.minColumns = minColumns;
      }

    /**

    • Parses and shows the content of one sheet using the specified styles and shared-strings
    • tables.
    • @param styles
    • @param strings

    • @param sheetInputStream
      */
      public List<String[]> processSheet(StylesTable styles, ReadOnlySharedStringsTable strings,
      InputStream sheetInputStream) throws IOException, ParserConfigurationException, SAXException {

      InputSource sheetSource = new InputSource(sheetInputStream);
      SAXParserFactory saxFactory = SAXParserFactory.newInstance();
      SAXParser saxParser = saxFactory.newSAXParser();
      XMLReader sheetParser = saxParser.getXMLReader();
      MyXSSFSheetHandler handler = new MyXSSFSheetHandler(styles, strings, this.minColumns, this.output);
      sheetParser.setContentHandler(handler);
      sheetParser.parse(sheetSource);
      return handler.getRows();
      }

    /**

    • 初始化这个处理程序 将
    • @throws IOException
    • @throws OpenXML4JException
    • @throws ParserConfigurationException

    • @throws SAXException
      */
      public List<String[]> process() throws IOException, OpenXML4JException, ParserConfigurationException, SAXException {

      ReadOnlySharedStringsTable strings = new ReadOnlySharedStringsTable(this.xlsxPackage);
      XSSFReader xssfReader = new XSSFReader(this.xlsxPackage);
      List<String[]> list = null;
      StylesTable styles = xssfReader.getStylesTable();
      XSSFReader.SheetIterator iter = (XSSFReader.SheetIterator) xssfReader.getSheetsData();
      while (iter.hasNext()) {
      InputStream stream = iter.next();
      list = processSheet(styles, strings, stream);
      stream.close();
      break;
      }
      return list;
      }

    /**

    • 读取Excel
    • @param path 文件路径
    • @param sheetName sheet名称
    • @param minColumns 列总数
    • @return
    • @throws SAXException
    • @throws ParserConfigurationException
    • @throws OpenXML4JException
    • @throws IOException
      */
      public static List<String[]> readerExcel(String path, int minColumns) throws IOException, OpenXML4JException,
      ParserConfigurationException, SAXException {
      OPCPackage p = OPCPackage.open(path, PackageAccess.READ);
      XLSXCovertCSVReader xlsx2csv = new XLSXCovertCSVReader(p, System.out, minColumns);
      List<String[]> list = xlsx2csv.process();
      p.close();
      return list;
      }

    /**

    • @param file
    • @param minColumns
    • @return
    • @throws IOException
    • @throws OpenXML4JException
    • @throws ParserConfigurationException
    • @throws SAXException
      */
      public static List<String[]> readerExcel(File file, int minColumns) throws IOException, OpenXML4JException,
      ParserConfigurationException, SAXException {
      OPCPackage p = OPCPackage.open(file, PackageAccess.READ);
      XLSXCovertCSVReader xlsx2csv = new XLSXCovertCSVReader(p, System.out, minColumns);
      List<String[]> list = xlsx2csv.process();
      p.close();
      return list;
      }

    /**

    • 读取Excel
    • @param path 文件路径
    • @param sheetName sheet名称
    • @param minColumns 列总数
    • @return
    • @throws SAXException
    • @throws ParserConfigurationException
    • @throws OpenXML4JException

    • @throws IOException
      */
      public static List<String[]> readerExcel(InputStream in, int minColumns) throws IOException, OpenXML4JException,
      ParserConfigurationException, SAXException {

      OPCPackage p = OPCPackage.open(in);
      XLSXCovertCSVReader xlsx2csv = new XLSXCovertCSVReader(p, System.out, minColumns);
      List<String[]> list = xlsx2csv.process();
      List<String[]> newlist=new ArrayList<>();
      p.close();
      for(String [] str:list){
      //判断excle 集合里是否有 All elements are null引起的异常
      if(!StringUtil.isEmpty(str[0])){
      newlist.add(str);
      }
      }
      return newlist;
      }

}

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