【转】java将excel文件转换成txt格式文件

       在实际应用中，我们难免会遇到解析excel文件入库事情，有时候为了方便，需要将excel文件转成txt格式文件。下面代码里面提供对xls、xlsx两种格式的excel文件解析，并写入到一个新的txt文件中，数据以分隔符逗号","隔开。

 excel文件如图所示: 

转换后的txt文件:

需要依赖4个jar包:

package com.xuan.excel;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStreamWriter;
import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
 


import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.DateUtil;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
 
/** 
* <p>版权所有：版权所有(C) 2014-2099</p>
* ──────────────────────────────────
* <p>作    者：青莲剑仙</p>
* ──────────────────────────────────
* <p>将excel转成TXT文本<p>
**/
public class ExcelToTxt {
 
    private static File [] getFiles(String path){
        File file = new File(path);
        // get the folder list
        File[] array = file.listFiles();
        return array;
    }
    
    public static void main(String[] args) throws IOException {
        File[] files=getFiles("D:\keyword");
        for(int i=0;i<files.length;i++){
            if (files[i].isFile()) {
                System.out.println("f=="+files[i].getPath()+"  "+files[i].getName());
                publishTxt(files[i].getPath());
            }
            if (files[i].isDirectory()) {
                System.out.println("d=="+files[i].getPath()+"  "+files[i].getName());
                File[] files2=getFiles(files[i].getPath());
                for(int j=0;j<files2.length;j++){
                    publishTxt(files2[j].getPath());
                }
                
            }
        }
    }
    
    public static void publishTxt(String excelPath){
        String columns[] = { "交易时间", "记账日期", "银行流水号", "商户流水号", "订单号", "订单状态", "付款方账号/客户号", "付款方户名",
                "订单金额", "交易金额", "手续费", "结算金额", "柜台代码", "发卡行/通道", "支付卡种", "交易类型", "期数", "授权号", "项目号",
                "基本户", "备注一", "备注二" };
        Workbook wb = null;
        Sheet sheet = null;
        Row row = null;
        List<Map<String, String>> list = null;
        String cellData = null;
        String fileType=excelPath.substring(excelPath.indexOf('.') + 1);

        
        wb = readExcel(excelPath);
        if (wb != null) {
            // 用来存放表中数据
            list = new ArrayList<Map<String, String>>();
            // 获取第一个sheet
            sheet = wb.getSheetAt(0);
            // 获取最大行数
            int rownum = sheet.getPhysicalNumberOfRows();
            // 获取第二行
            row = sheet.getRow(1);
            // 获取最大列数
            int colnum = row.getPhysicalNumberOfCells();
            for (int i = 0; i < rownum; i++) {
                Map<String, String> map = new LinkedHashMap<String, String>();
                row = sheet.getRow(i);
                if (row != null) {
                    for (int j = 0; j < colnum; j++) {
                        cellData = (String) getCellFormatValue(row.getCell(j));
                        map.put(columns[j], cellData);
                    }
                } else {
                    break;
                }
                list.add(map);
            }
        }
        // 遍历解析出来的list
        StringBuffer sb = new StringBuffer();
        for (int i = 0; i < list.size(); i++) {
            for (Entry<String, String> entry : list.get(i).entrySet()) {
                String value = entry.getValue();
                sb.append(value+",");
            }
            sb.append("
");
        }
        try {
            WriteToFile(sb.toString(), excelPath.replace(".xlsx", ".txt"));
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        
        System.out.println("*************EXCEL转成TXT格式成功*************");
        
    }
 
    // 读取excel
    public static Workbook readExcel(String filePath) {
        Workbook wb = null;
        if (filePath == null) {
            return null;
        }
        String extString = filePath.substring(filePath.lastIndexOf("."));
        InputStream is = null;
        try {
            is = new FileInputStream(filePath);
            if (".xls".equals(extString)) {
                return wb = new HSSFWorkbook(is);
            } else if (".xlsx".equals(extString)) {
                return wb = new XSSFWorkbook(is);
            } else {
                return wb = null;
            }
 
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return wb;
    }
 
    public static Object getCellFormatValue(Cell cell) {
        Object cellValue = null;
        if (cell != null) {
            // 判断cell类型
            switch (cell.getCellType()) {
            case Cell.CELL_TYPE_NUMERIC: {
                cellValue = String.valueOf(cell.getNumericCellValue());
                break;
            }
            case Cell.CELL_TYPE_FORMULA: {
                try{
                // 判断cell是否为日期格式
                if (DateUtil.isCellDateFormatted(cell)) {
                    // 转换为日期格式YYYY-mm-dd
                    cellValue = cell.getRichStringCellValue().getString();//cell.getDateCellValue();
                } else {
                    // 数字
                    cellValue =cell.getRichStringCellValue().getString(); //String.valueOf(cell.getNumericCellValue());
                }
                }catch(Exception ex){}
                break;
            }
            case Cell.CELL_TYPE_STRING: {
                cellValue = cell.getRichStringCellValue().getString();
                break;
            }
            default:
                cellValue = "";
            }
        } else {
            cellValue = "";
        }
        return cellValue;
    }
 
    /**
     * 生成文件
     * @param str
     * @param filePath
     * @throws IOException 
     */
 
    public static void WriteToFile(String str, String filePath) throws IOException {
        BufferedWriter bw = null;
        try {
            FileOutputStream out = new FileOutputStream(filePath, true);// true,表示:文件追加内容，不重新生成,默认为false
            bw = new BufferedWriter(new OutputStreamWriter(out, "GBK"));
            bw.write(str += "
");// 换行
            bw.flush();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            bw.close();
        }
    }
}

from：https://blog.csdn.net/usuallyuser/article/details/81217122