java 操作Excel

public class WriteExcel {
    private static final String EXCEL_XLS = "xls";
    private static final String EXCEL_XLSX = "xlsx";



    public static void main(String[] Args) throws IOException{
        Map<String,String> map = new HashMap<>();

        //只有第2/3/4/5列需要重新填写，其他的默认即可
        map.put("m1","XXX1"+1234);
        map.put("m2","XXX1"+4321);
        map.put("m3","10001");
        map.put("m4","0-1-11");
        writeExcel(map, 4, "C:\\Users\\Administrator\\Desktop\\template .xls");
    }
    public static void writeExcel(Map dataList, int cloumnCount,String finalXlsxPath) throws IOException{
        OutputStream out = null;
        try {
            // 获取总列数
//            int columnNumCount = cloumnCount;
            // 读取Excel文档
            File finalXlsxFile = new File(finalXlsxPath);
            Workbook workBook = getWorkbok(finalXlsxFile);
            // sheet 对应一个工作页
            Sheet sheet = workBook.getSheetAt(0);
            /**
             * 往Excel中写新数据
             */


                // 创建一行：从第三行开始，跳过标题列、属性列
//                Row row = sheet.createRow(2);
                  Row row = sheet.getRow(2);
                // 得到要插入的每一条记录
                Map map = dataList;
             String[] n = new String[columnNumCount];

            for (int k = 0; k <columnNumCount; k++) {

                // 在一行内循环
                String aa = "m"+(k+1);
                n[k] = map.get(aa).toString();
                Cell c1 = row.createCell(k+1);
                c1.setCellValue(n[k]);


               }

            // 创建文件输出流，准备输出电子表格：这个必须有，否则你在sheet上做的任何操作都不会有效
            out =  new FileOutputStream(finalXlsxPath);
            workBook.write(out);
        } catch (Exception e) {
            e.printStackTrace();
        } finally{
            try {
                if(out != null){
                    out.flush();
                    out.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        System.out.println("数据导出成功");
    }

    /**
     * 判断Excel的版本,获取Workbook
     * @return
     * @throws IOException
     */
    public static Workbook getWorkbok(File file) throws IOException{
        Workbook wb = null;
        FileInputStream in = new FileInputStream(file);
        if(file.getName().endsWith(EXCEL_XLS)){  //Excel 2003
            wb = new HSSFWorkbook(in);
        }else if(file.getName().endsWith(EXCEL_XLSX)){  // Excel 2007/2010
            wb = new XSSFWorkbook(in);
        }
        return wb;
    }
}