Java利用Reflect实现封装Excel导出工具类

@Getter
@RequiredArgsConstructor
public enum ExcelExportEnum {

/**
 * 模块
 */
MODULE_A("moduleAService", "模块A");

private final String key;
private final String name;

}

    if (!map.containsKey(MODULE_NAME)) {
        throw new BaseException("缺少参数：moduleName");
    }
    String moduleName = map.get(MODULE_NAME).toString();
    if (!EnumUtil.contains(ExcelExportEnum.class, moduleName)) {
        throw new BaseException("模块查找失败");
    }
    String functionName = DEFAULT_FUNCTION_NAME;
    //如果传了自定义方法名
    if (map.containsKey(CUSTOM_FUNCTION_NAME)) {
        functionName = map.get(CUSTOM_FUNCTION_NAME).toString();
    }
    String serviceName = ExcelExportEnum.valueOf(moduleName).getKey();
    String tableName = ExcelExportEnum.valueOf(moduleName).getName();

Map<String, Method> methodMap = Arrays.stream(SpringContextHolder.getBean(serviceName).getClass().getMethods()).collect(Collectors.toMap(Method::getName, Function.identity(), (key1, key2) -> key2));

    Object o;
    try {
        o = methodMap.get(functionName).getParameterTypes()[0].getDeclaredConstructor().newInstance();
    } catch (Exception e) {
        throw new BaseException(e);
    }

    Map<String, Object> param = (Map<String, Object>) map.computeIfAbsent(PARAM, k -> new HashMap<String, Object>(4));
    param.put("limit", -1);
    CopyOptions copyOptions = new CopyOptions();
    copyOptions.setIgnoreError(true);
    PageUtils page = (PageUtils) methodMap.get(functionName).invoke(SpringContextHolder.getBean(serviceName), BeanUtil.mapToBean(param, o.getClass(), true, copyOptions));
    if (CollUtil.isEmpty(page.getList())) {
        throw new BaseException("数据获取失败");
    }
    Object resultObject = page.getList().get(0);
    ExcelUtils utils = new ExcelUtils(resultObject.getClass());
    utils.exportExcel(page.getList(), response, tableName, moduleName);

// 通过工具类创建writer，默认创建xls格式 
ExcelWriter writer = ExcelUtil.getWriter(); 
//创建xlsx格式的 
//ExcelWriter writer = ExcelUtil.getWriter(true); 
// 一次性写出内容，使用默认样式，强制输出标题 
writer.write(rows, true); 
//out为OutputStream，需要写出到的目标流 
writer.flush(out); 
// 关闭writer，释放内存 
writer.close();