easypoi导出动态列及多级复杂表头java代码，要求不能定义实体类存储数据

使用Easypoi导出动态列及多级复杂表头可以通过编写自定义的导出类来实现，以下是一个示例代码：

public class CustomExportUtil {
    /**
     * 导出Excel
     *
     * @param title        标题
     * @param headers      表头
     * @param dataList     数据列表
     * @param dateFormat   日期格式
     * @param response     HttpServletResponse对象
     * @throws IOException
     */
    public static void exportExcel(String title, List<ExcelHeader> headers, List<Map<String, Object>> dataList, String dateFormat, HttpServletResponse response) throws IOException {
        // 创建Excel对象
        Workbook workbook = new SXSSFWorkbook(1000);
        // 创建Sheet对象
        Sheet sheet = workbook.createSheet(title);
        // 设置默认列宽
        sheet.setDefaultColumnWidth(15);

        // 创建第一行，设置表头
        Row headerRow = sheet.createRow(0);
        int colIndex = 0;
        for (ExcelHeader header : headers) {
            Cell cell = headerRow.createCell(colIndex++);
            cell.setCellValue(header.getTitle());
            // 设置合并单元格
            if (header.getColSpan() > 1 || header.getRowSpan() > 1) {
                CellRangeAddress rangeAddress = new CellRangeAddress(0, header.getRowSpan() - 1, colIndex - 1, colIndex + header.getColSpan() - 2);
                sheet.addMergedRegion(rangeAddress);
            }
        }

        // 填充数据
        int rowIndex = 1;
        for (Map<String, Object> data : dataList) {
            Row row = sheet.createRow(rowIndex++);
            colIndex = 0;
            for (ExcelHeader header : headers) {
                // 获取数据
                Object value = data.get(header.getFieldName());
                // 格式化日期
                if (value instanceof Date) {
                    value = new SimpleDateFormat(dateFormat).format(value);
                }
                Cell cell = row.createCell(colIndex++);
                cell.setCellValue(String.valueOf(value));
            }
        }

        // 设置响应头
        response.setContentType("application/octet-stream;charset=utf-8");
        response.setHeader("Content-Disposition", "attachment;filename=" + new String((title + ".xlsx").getBytes("utf-8"), "iso8859-1"));

        // 输出Excel文件
        OutputStream outputStream = response.getOutputStream();
        workbook.write(outputStream);
        outputStream.flush();
        outputStream.close();
    }
}

其中，ExcelHeader类表示表头信息，包括标题、字段名、列合并数、行合并数等信息：

public class ExcelHeader {
    /**
     * 标题
     */
    private String title;
    /**
     * 字段名
     */
    private String fieldName;
    /**
     * 列合并数
     */
    private int colSpan;
    /**
     * 行合并数
     */
    private int rowSpan;

    public ExcelHeader(String title, String fieldName, int colSpan, int rowSpan) {
        this.title = title;
        this.fieldName = fieldName;
        this.colSpan = colSpan;
        this.rowSpan = rowSpan;
    }

    // getter/setter方法省略
}

使用示例：

List<ExcelHeader> headers = new ArrayList<>();
headers.add(new ExcelHeader("姓名", "name", 1, 1));
headers.add(new ExcelHeader("年龄", "age", 1, 1));
headers.add(new ExcelHeader("联系方式", null, 2, 1));
headers.add(new ExcelHeader("电话", "phone", 1, 1));
headers.add(new ExcelHeader("邮箱", "email", 1, 1));
headers.add(new ExcelHeader("地址", "address", 1, 1));
headers.add(new ExcelHeader("省份", "province", 1, 1));
headers.add(new ExcelHeader("城市", "city", 1, 1));
headers.add(new ExcelHeader("区县", "county", 1, 1));

List<Map<String, Object>> dataList = new ArrayList<>();
Map<String, Object> data1 = new HashMap<>();
data1.put("name", "张三");
data1.put("age", 20);
data1.put("phone", "123456789");
data1.put("email", "zhangsan@example.com");
data1.put("address", "北京市朝阳区");
data1.put("province", "北京市");
data1.put("city", "北京市");
data1.put("county", "朝阳区");
dataList.add(data1);

CustomExportUtil.exportExcel("学生信息表", headers, dataList, "yyyy-MM-dd HH:mm:ss", response);