Java自定义列导出Excel

@Data
public class ColumnConfig {

    @ApiModelProperty(value = "Excel列名")
    private String columnName;

    @ApiModelProperty(value = "实体类字段名")
    private String fieldName;
}

public class ExcelUtils {

    /**
     * Excel导出（使用注解导出固定列数据）
     *
     * @param response  response
     * @param fileName  文件名
     * @param sheetName sheetName
     * @param list      数据List
     * @param pojoClass 对象Class
     */
    public static void exportExcel(HttpServletResponse response, String fileName, String sheetName, List<?> list,
                                   Class<?> pojoClass) throws IOException {
        fileName = URLEncoder.encode(fileName, "UTF-8");
        response.setHeader("Access-Control-Allow-Origin", "*");
        response.setHeader("Access-Control-Expose-Headers", " Content-Disposition");
        response.setHeader("Content-Disposition", "attachment;filename=" + fileName);
        response.setContentType("application/octet-stream; charset = UTF-8");
        EasyExcel.write(response.getOutputStream(), pojoClass).registerConverter(new LongStringConverter()).sheet(sheetName).doWrite(list);
    }


    /**
     *
     * Excel导出（自定义列数据）
     *
     * @param response response
     * @param fileName 文件名
     * @param sheetName sheetName
     * @param columnConfigs 自定义列数据
     * @param list 数据List
     * @throws IOException
     */
    public static void customizeExportExcel(HttpServletResponse response, String fileName, String sheetName,
                                            List<ColumnConfig> columnConfigs, List<?> list) throws IOException {

        fileName = URLEncoder.encode(fileName, "UTF-8");
        response.setHeader("Access-Control-Allow-Origin", "*");
        response.setHeader("Access-Control-Expose-Headers", " Content-Disposition");
        response.setHeader("Content-Disposition", "attachment;filename=" + fileName);
        response.setContentType("application/octet-stream; charset = UTF-8");
        EasyExcel.write(response.getOutputStream())
                .head(buildExcelHead(columnConfigs))
                .sheet(sheetName)
                .doWrite(buildExcelDataBody(columnConfigs, list));
    }


    /**
     * 构建表头（多级表头需嵌套List）
     * @param columnConfigs
     * @return
     */
    private static List<List<String>> buildExcelHead(List<ColumnConfig> columnConfigs) {
        List<List<String>> head = new ArrayList<>();
        for (ColumnConfig config : columnConfigs) {
            head.add(Collections.singletonList(config.getColumnName()));
        }
        return head;
    }

    /**
     * 构建数据体（通过反射获取字段值）
     * @param columnConfigs
     * @param dataList
     * @return
     */
    private static List<List<Object>> buildExcelDataBody(List<ColumnConfig> columnConfigs, List<?> dataList) {
        List<List<Object>> dataBody = new ArrayList<>();
        for (Object entity : dataList) {
            List<Object> row = new ArrayList<>();
            for (ColumnConfig config : columnConfigs) {
                Object value = getFieldValueByReflect(entity, config.getFieldName());
                row.add(value);
            }
            dataBody.add(row);
        }
        return dataBody;
    }

    /**
     * 反射获取字段值（优先通过get方法）
     * @param obj
     * @param fieldName
     * @return
     */
    private static Object getFieldValueByReflect(Object obj, String fieldName) {
        try {
            // 构造get方法名（如：getUserName）
            String getMethodName = "get" + fieldName.substring(0, 1).toUpperCase() + fieldName.substring(1);
            Method method = obj.getClass().getMethod(getMethodName);
            return method.invoke(obj);
        } catch (NoSuchMethodException | IllegalAccessException | InvocationTargetException e) {
            // 若get方法不存在，尝试直接访问字段
            try {
                Field field = obj.getClass().getDeclaredField(fieldName);
                field.setAccessible(true);
                return field.get(obj);
            } catch (NoSuchFieldException | IllegalAccessException ex) {
                ex.printStackTrace();
                return "N/A";
            }
        }
    }
}