为这个问题搞了一上午，效率太低了。在代码中加一句
System.out.println("Constant.APPKEY= "+Constant.APPKEY);
重新读取Constant.APPKEY值，就好了。不知道为什么idea不去读取我修改后的常量值？哪位大神能解释一下？
10:57:35.264 [main] ERROR topsdk - 2021-03-05 10:57:35.236^_^_dingtalk_^_^dingtalk.oapi.call_back.delete_call_back^_^192.168.134.1^_^Windows 7^_^199^_^https://oapi.dingtalk.com/call_back/delete_call_back^_^access_token=820b08f8a1993c03ac535b599fefe0dc^_^{"errcode":60020,"errmsg":"请参考FAQ：https://open-doc.dingtalk.com/microapp/faquestions/cvbtph。错误原因：访问ip不在白名单之中,request ip=117.66.147.82 appKey\u0028ding8z60pmxhe0kg5voa\u0029"}
10:57:35.690 [main] ERROR topsdk - 2021-03-05 10:57:35.689^_^_dingtalk_^_^dingtalk.oapi.call_back.register_call_back^_^192.168.134.1^_^Windows 7^_^202^_^https://oapi.dingtalk.com/call_back/register_call_back^_^access_token=820b08f8a1993c03ac535b599fefe0dc&aes_key=0123456789abcdefghijklmnopqrstuvwxyzABCDEFG&call_back_tag=%5B%22bpms_instance_change%22%2C%22bpms_task_change%22%5D&url=http%3A%2F%2Ffang.vaiwan.com%2Fcallback&token=12345^_^{"errcode":60020,"errmsg":"请参考FAQ：https://open-doc.dingtalk.com/microapp/faquestions/cvbtph。错误原因：访问ip不在白名单之中,request ip=117.66.147.82 appKey\u0028ding8z60pmxhe0kg5voa\u0029"}