What causes "必填字段【%s】必须提供值！" in binarywang/WxJava?

Inspect the exception message — it names the exact missing required field(s).

binarywang/WxJava · error · WxErrorException

必填字段【%s】必须提供值！

Error message

必填字段【%s】必须提供值！

What it means

BeanUtils.checkRequiredFields reflects over a bean's fields annotated as required and collects any that are null/empty; if any are missing it throws WxErrorException listing them. This is used to validate request beans before sending them to WeChat, so required fields are enforced client-side with a clear message rather than failing opaquely server-side.

Source

Thrown at weixin-java-common/src/main/java/me/chanjar/weixin/common/util/BeanUtils.java:60

          // 另外一种情况是类型为字符串，但是字符串内容为空的，都认为是没有提供值
          boolean isRequiredMissing = field.get(bean) == null
            || (field.get(bean) instanceof String
            && StringUtils.isBlank(field.get(bean).toString())
          );
          if (isRequiredMissing) {
            requiredFields.add(field.getName());
          }
        }
        field.setAccessible(isAccessible);
      } catch (SecurityException | IllegalArgumentException | IllegalAccessException e) {
        log.error(e.getMessage(), e);
      }
    }

    if (!requiredFields.isEmpty()) {
      String msg = String.format("必填字段【%s】必须提供值！", requiredFields);
      log.debug(msg);
      throw new WxErrorException(msg);
    }
  }

}

View on GitHub (pinned to 1c43293a3c)

Solutions

Inspect the exception message — it names the exact missing required field(s).
Populate the listed field(s) on the bean before retrying the API call.
Use a builder/factory that enforces required fields at construction time.
After WxJava upgrades, diff request beans for newly-required fields.

Example fix

// before — required field 'appId' left null
WxSomeRequest req = new WxSomeRequest();
req.setSecret(secret);
service.doSomething(req); // throws: 必填字段【appId】必须提供值！

// after
WxSomeRequest req = new WxSomeRequest();
req.setAppId(appId);
req.setSecret(secret);
service.doSomething(req);

Defensive patterns

Strategy: validation

Validate before calling

// Validate required fields before the call — let BeanUtils name them,
// or pre-check known required fields:
if (req.getAppId() == null || req.getSecret() == null) {
  throw new IllegalArgumentException("appId/secret required");
}

Try / catch

try {
  service.doSomething(req);
} catch (WxErrorException e) {
  if (e.getMessage() != null && e.getMessage().contains("必填字段")) {
    // message names the missing field(s) — populate and retry
  }
  throw e;
}

Prevention

Read the exception message — it lists the exact missing required field(s).
Use a builder/factory that enforces required fields at construction.
After WxJava upgrades, diff request beans for newly-required fields.

When it happens

Trigger: Building a request bean (e.g. a WxMp/Channel/CP request object) and calling an API without populating one or more fields marked as required by the SDK's validation annotations.

Common situations: A new required field added in a WxJava upgrade that existing bean-construction code does not set; conditional logic that skips setting a required field for a particular request variant; copy-paste bean construction omitting a field.

Related errors

AI-assisted analysis of binarywang/WxJava@1c43293a3c (2026-08-14). Data as JSON: /api/errors/7659efb8383c8352. Report an issue: GitHub.