sentinel1.8.4 不能注册服务

java -jar --add-exports=java.base/sun.net.util=ALL-UNNAMED sentinel-dashboard-1.8.4.jar

该问题在 Jdk 1.8.0_131 则不会出现，Sentinel 正常运行和监测心跳。
但在 17.0.1.12 下，启动被监测服务时 Sentinel 会报错反射失败。
系统环境为 Windows。

堆栈信息：

1.  
   2022-04-22 22:24:38.343 ERROR 2596 --- [nio-8080-exec-7] o.a.c.c.C.[.[.[/].[dispatcherServlet] : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Handler dispatch failed; nested exception is java.lang.IllegalAccessError: class com.alibaba.csp.sentinel.dashboard.controller.MachineRegistryController (in unnamed module @0x73d49a8) cannot access class sun.net.util.IPAddressUtil (in module java.base) because module java.base does not export sun.net.util to unnamed module @0x73d49a8] with root cause
2.  
    
3.  
   java.lang.IllegalAccessError: class com.alibaba.csp.sentinel.dashboard.controller.MachineRegistryController (in unnamed module @0x73d49a8) cannot access class sun.net.util.IPAddressUtil (in module java.base) because module java.base does not export sun.net.util to unnamed module @0x73d49a8
4.  
   at com.alibaba.csp.sentinel.dashboard.controller.MachineRegistryController.receiveHeartBeat(MachineRegistryController.java:55) ~[classes!/:na]
5.  
   at jdk.internal.reflect.GeneratedMethodAccessor50.invoke(Unknown Source) ~[na:na]
6.  
   at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
7.  
   at java.base/java.lang.reflect.Method.invoke(Method.java:568) ~[na:na]
8.  
   at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205) ~[spring-web-5.3.18.jar!/:5.3.18]
9.  
   at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:150) ~[spring-web-5.3.18.jar!/:5.3.18]
10.  
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:117) ~[spring-webmvc-5.3.18.jar!/:5.3.18]
11.  
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895) ~[spring-webmvc-5.3.18.jar!/:5.3.18]
12.  
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:808) ~[spring-webmvc-5.3.18.jar!/:5.3.18]
13.  
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-5.3.18.jar!/:5.3.18]
14.  
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1067) ~[spring-webmvc-5.3.18.jar!/:5.3.18]
15.  
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:963) ~[spring-webmvc-5.3.18.jar!/:5.3.18]
16.  
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) ~[spring-webmvc-5.3.18.jar!/:5.3.18]
17.  
    at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:909) ~[spring-webmvc-5.3.18.jar!/:5.3.18]
18.  
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:681) ~[tomcat-embed-core-9.0.60.jar!/:na]
19.  
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) ~[spring-webmvc-5.3.18.jar!/:5.3.18]
20.  
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:764) ~[tomcat-embed-core-9.0.60.jar!/:na]
21.  
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227) ~[tomcat-embed-core-9.0.60.jar!/:na]
22.  
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.60.jar!/:na]
23.  
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ~[tomcat-embed-websocket-9.0.60.jar!/:na]
24.  
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.60.jar!/:na]
25.  
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.60.jar!/:na]
26.  
    at com.alibaba.csp.sentinel.adapter.servlet.CommonFilter.doFilter(CommonFilter.java:110) ~[sentinel-web-servlet-1.8.4.jar!/:na]
27.  
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.60.jar!/:na]
28.  
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.60.jar!/:na]
29.  
    at com.alibaba.csp.sentinel.dashboard.auth.DefaultLoginAuthenticationFilter.doFilter(DefaultLoginAuthenticationFilter.java:89) ~[classes!/:na]
30.  
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.60.jar!/:na]
31.  
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.60.jar!/:na]
32.  
    at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) ~[spring-web-5.3.18.jar!/:5.3.18]
33.  
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.18.jar!/:5.3.18]
34.  
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.60.jar!/:na]
35.  
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.60.jar!/:na]
36.  
    at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) ~[spring-web-5.3.18.jar!/:5.3.18]
37.  
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.18.jar!/:5.3.18]
38.  
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.60.jar!/:na]
39.  
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.60.jar!/:na]
40.  
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) ~[spring-web-5.3.18.jar!/:5.3.18]
41.  
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.18.jar!/:5.3.18]
42.  
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.60.jar!/:na]
43.  
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.60.jar!/:na]
44.  
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:197) ~[tomcat-embed-core-9.0.60.jar!/:na]
45.  
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97) ~[tomcat-embed-core-9.0.60.jar!/:na]
46.  
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541) ~[tomcat-embed-core-9.0.60.jar!/:na]
47.  
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:135) ~[tomcat-embed-core-9.0.60.jar!/:na]
48.  
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) ~[tomcat-embed-core-9.0.60.jar!/:na]
49.  
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78) ~[tomcat-embed-core-9.0.60.jar!/:na]
50.  
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:360) ~[tomcat-embed-core-9.0.60.jar!/:na]
51.  
    at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:399) ~[tomcat-embed-core-9.0.60.jar!/:na]
52.  
    at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) ~[tomcat-embed-core-9.0.60.jar!/:na]
53.  
    at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:889) ~[tomcat-embed-core-9.0.60.jar!/:na]
54.  
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1743) ~[tomcat-embed-core-9.0.60.jar!/:na]
55.  
    at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) ~[tomcat-embed-core-9.0.60.jar!/:na]
56.  
    at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191) ~[tomcat-embed-core-9.0.60.jar!/:na]
57.  
    at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659) ~[tomcat-embed-core-9.0.60.jar!/:na]
58.  
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) ~[tomcat-embed-core-9.0.60.jar!/:na]
59.  
    at java.base/java.lang.Thread.run(Thread.java:833) ~[na:an]

问题应该是出于 Java 16 后默认不允许对 JDK 的内部模块进行反射，参考 Oracle Doc：
Illegal Reflective Access [link]：
一些工具和库使用反射来访问 JDK 中仅供内部使用的部分。这称为非法反射访问，默认情况下不允许在 JDK 16 及更高版本中访问。
默认情况下，使用直接访问 JDK 内部 API 的早期版本成功编译的代码将不再有效

解决方案目前只找到了在启动时增加 --add-export 参数，来允许 Sentinel 调用 java.base/sun.net.util：

java -jar --add-exports=java.base/sun.net.util=ALL-UNNAMED sentinel-dashboard-1.8.4.jar

不知可否有更好的解决方案，从

而避免每次都从启动参数上下手

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