Big Excel POI导出

BigExcelReaderUtil.java

package com.xxxx.tools;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.InputStream;

import java.sql.SQLException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.Iterator;

import java.util.List;

import org.apache.poi.xssf.eventusermodel.XSSFReader;

import org.apache.poi.xssf.model.SharedStringsTable;

import org.apache.poi.xssf.usermodel.XSSFRichTextString;
import org.apache.poi.openxml4j.opc.OPCPackage;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
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 org.xml.sax.helpers.XMLReaderFactory;

import com.monitorjbl.xlsx.StreamingReader;

/**
 * XSSF and SAX (Event API)
 */

public abstract class BigExcelReaderUtil extends DefaultHandler {

    private SharedStringsTable sst;

    private String lastContents;

    private boolean nextIsString;

    private int sheetIndex = -1;

    private List<String> rowlist = new ArrayList<String>();

    private int curRow = 0; // 当前行

    private int curCol = 0; // 当前列索引

    private int preCol = 0; // 上一列列索引

    private int titleRow = 0; // 标题行，一般情况下为0

    private int rowsize = 0; // 列数

    // 日期标志
    private boolean dateFlag;

    private String dateFormat;

    //excel记录行操作方法，以sheet索引，行索引和行元素列表为参数，对sheet的一行元素进行操作，元素为String类型

    public abstract void optRows(int sheetIndex, int curRow, List<String> rowlist) throws SQLException;

    //只遍历一个sheet，其中sheetId为要遍历的sheet索引，从1开始，1-3

    /**
     *
     * @param filename
     * @param sheetId  sheetId为要遍历的sheet索引，从1开始，1-3
     * @throws Exception
     */

    public void processOneSheet(String filename, int sheetId) throws Exception {

        OPCPackage pkg = OPCPackage.open(filename);

        XSSFReader r = new XSSFReader(pkg);

        SharedStringsTable sst = r.getSharedStringsTable();

        XMLReader parser = fetchSheetParser(sst);

        // rId2 found by processing the Workbook

        // 根据 rId# 或 rSheet# 查找sheet

        InputStream sheet2 = r.getSheet("rId" + sheetId);

        sheetIndex++;

        InputSource sheetSource = new InputSource(sheet2);

        parser.parse(sheetSource);

        sheet2.close();

    }

    /**
     * 遍历 excel 文件
     */

    public void process(String filename) throws Exception {

        OPCPackage pkg = OPCPackage.open(filename);

        XSSFReader r = new XSSFReader(pkg);

        SharedStringsTable sst = r.getSharedStringsTable();

        XMLReader parser = fetchSheetParser(sst);

        Iterator<InputStream> sheets = r.getSheetsData();

        while (sheets.hasNext()) {

            curRow = 0;

            sheetIndex++;

            InputStream sheet = sheets.next();

            InputSource sheetSource = new InputSource(sheet);

            parser.parse(sheetSource);

            sheet.close();

        }

    }

    public XMLReader fetchSheetParser(SharedStringsTable sst) throws SAXException {

        XMLReader parser = XMLReaderFactory.createXMLReader();
        //XMLReader parser = XMLReaderFactory.createXMLReader("org.apache.xerces.parsers.SAXParser");
        this.sst = sst;

        parser.setContentHandler(this);

        return parser;

    }

    public void startElement(String uri, String localName, String name, Attributes attributes) throws SAXException {

        // c => 单元格
        if (name.equals("c")) {

            // 如果下一个元素是 SST 的索引，则将nextIsString标记为true
            String cellType = attributes.getValue("t");
            String rowStr = attributes.getValue("r");
            curCol = this.getRowIndex(rowStr);
            if (cellType != null && cellType.equals("s")) {
                nextIsString = true;
            } else {
                nextIsString = false;
            }

            // 日期格式
            String cellDateType = attributes.getValue("s");
            if ("1".equals(cellDateType) ){
                dateFlag = true;
                dateFormat="yyyy-MM-dd";
            }else if( "2".equals(cellDateType) ||  "3".equals(cellDateType) 
                     //||  "6".equals(cellDateType) || "7".equals(cellDateType) 
                    ) {
                dateFlag = true;
                dateFormat="yyyy-MM-dd hh:mm:ss";
            //}else if(   "4".equals(cellDateType)  
                //    ||  "5".equals(cellDateType)     ) {
            //    dateFlag = true;
            //    dateFormat="yyyy-MM-dd";
            //}else if( "8".equals(cellDateType)  ||  "9".equals(cellDateType)  ){
                //dateFlag = true;
                //dateFormat="hh:mm:ss";
            }else {
                dateFormat="";
                dateFlag = false;
            }

        }

        // 置空
        lastContents = "";
    }

    public void endElement(String uri, String localName, String name) throws SAXException {

        // 根据SST的索引值的到单元格的真正要存储的字符串
        // 这时characters()方法可能会被调用多次
        if (nextIsString) {
            try {
                int idx = Integer.parseInt(lastContents);
                lastContents = new XSSFRichTextString(sst.getEntryAt(idx)).toString();
            } catch (Exception e) {

            }
        }

        // v => 单元格的值，如果单元格是字符串则v标签的值为该字符串在SST中的索引
        // 将单元格内容加入rowlist中，在这之前先去掉字符串前后的空白符

        if (name.equals("v")) {

            String value = lastContents.trim();


            value = value.equals("") ? " " : value;
            try {
                // 日期格式处理
                if (dateFlag) {
                    if(value.length()==5) {
                        Date date = org.apache.poi.ss.usermodel.DateUtil.getJavaDate(Double.valueOf(value));
                        SimpleDateFormat sdf = new SimpleDateFormat(dateFormat);
                        value = sdf.format(date);
                    }
                }
            } catch (Exception e) {
                // 转换失败仍用读出来的值
            }



            int cols = curCol - preCol;
            if (cols > 1) {

                for (int i = 0; i < cols - 1; i++) {
                    rowlist.add(preCol, "");
                }

            }

            preCol = curCol;
            rowlist.add(curCol - 1, value);

        } else {
            //如果标签名称为 row ，这说明已到行尾，调用 optRows() 方法
            if (name.equals("row")) {

                int tmpCols = rowlist.size();

                if (curRow > this.titleRow && tmpCols < this.rowsize) {

                    for (int i = 0; i < this.rowsize - tmpCols; i++) {

                        rowlist.add(rowlist.size(), "");

                    }

                }

                try {

                    optRows(sheetIndex, curRow, rowlist);

                } catch (SQLException e) {

                    e.printStackTrace();

                }

                if (curRow == this.titleRow) {

                    this.rowsize = rowlist.size();

                }

                rowlist.clear();

                curRow++;

                curCol = 0;

                preCol = 0;

            }

        }

    }

    public void characters(char[] ch, int start, int length) throws SAXException {
        //得到单元格内容的值
        lastContents += new String(ch, start, length);
    }
    //得到列索引，每一列c元素的r属性构成为字母加数字的形式，字母组合为列索引，数字组合为行索引，
    //如AB45,表示为第（A-A+1）*26+（B-A+1）*26列，45行
    public int getRowIndex(String rowStr) {

        rowStr = rowStr.replaceAll("[^A-Z]", "");

        byte[] rowAbc = rowStr.getBytes();

        int len = rowAbc.length;

        float num = 0;

        for (int i = 0; i < len; i++) {

            num += (rowAbc[i] - 'A' + 1) * java.lang.Math.pow(26, len - i - 1);

        }

        return (int) num;

    }

    public int getTitleRow() {

        return titleRow;

    }

    public void setTitleRow(int titleRow) {

        this.titleRow = titleRow;

    }
    public static Row getFirstRow(String fileUrl)   {
        try {
            FileInputStream is = new FileInputStream(new File(fileUrl));
            final Workbook workbook = StreamingReader.builder()
                    .rowCacheSize(100)
                    .bufferSize(4096)
                    .open(is);
            Sheet sheet = workbook.getSheetAt(0);
            Row row = sheet.rowIterator().next();

            return row;
        } catch (FileNotFoundException e) {
            e.printStackTrace();
            return null;
        }
    }


    //如何使用
    public static void main(String[] args) throws Exception {

        long start = System.currentTimeMillis();

        BigExcelReaderUtil xlx = new BigExcelReaderUtil() {
            @Override
            public void optRows(int sheetIndex, int curRow, List<String> rowlist) throws SQLException {
                System.out.println(rowlist);
            }

        };

        xlx.process("E:\\data\\files\\s\\20220427ISLLMF87.xlsx");

        long end = System.currentTimeMillis();

        System.out.println((end - start) / 1000);

    }

}

使用

获得标题

Row     row = BigExcelReaderUtil.getFirstRow(fileUrl);

获得内容

BigExcelReaderUtil xlsx = new BigExcelReaderUtil(){

                                @Override
                                public void optRows(int sheetIndex, int curRow, List<String> rowList) {
                                   //标题
                                   if(curRow==0) {

                                   }
                                   //非标题
                                   if(curRow>0) {
                                }
};
xlsx.processOneSheet(fileUrl,1);