1.反射兼容问题

这是由于 JDK 8 中有关反射相关的功能自从 JDK 9 开始就已经被限制了，为了兼容原先的版本，需要在运行项目时添加 --add-opens java.base/java.lang=ALL-UNNAMED 选项来开启这种默认不被允许的行为。

2.报错信息

java.lang.reflect.InaccessibleObjectException: Unable to make protected final java.lang.Class java.lang.ClassLoader.defineClass(java.lang.String,byte[],int,int,java.security.ProtectionDomain) throws java.lang.ClassFormatError accessible: module java.base does not "opens java.lang" to unnamed module @59fd97a8
	at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:354) ~[na:na]
	at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:297) ~[na:na]
	at java.base/java.lang.reflect.Method.checkCanSetAccessible(Method.java:200) ~[na:na]
	at java.base/java.lang.reflect.Method.setAccessible(Method.java:194) ~[na:na]
	at javassist.util.proxy.SecurityActions.setAccessible(SecurityActions.java:159) ~[javassist-3.29.1-GA.jar:na]
	at javassist.util.proxy.DefineClassHelper$JavaOther.defineClass(DefineClassHelper.java:213) ~[javassist-3.29.1-GA.jar:na]
	at javassist.util.proxy.DefineClassHelper$Java11.defineClass(DefineClassHelper.java:52) ~[javassist-3.29.1-GA.jar:na]
	at javassist.util.proxy.DefineClassHelper.toClass(DefineClassHelper.java:260) ~[javassist-3.29.1-GA.jar:na]
	at javassist.ClassPool.toClass(ClassPool.java:1240) ~[javassist-3.29.1-GA.jar:na]
	at javassist.ClassPool.toClass(ClassPool.java:1098) ~[javassist-3.29.1-GA.jar:na]
	at javassist.ClassPool.toClass(ClassPool.java:1056) ~[javassist-3.29.1-GA.jar:na]
	at javassist.CtClass.toClass(CtClass.java:1298) ~[javassist-3.29.1-GA.jar:na]
	at com.kang.javassist.service.impl.JavassistServiceImpl.addMethodByJavassist(JavassistServiceImpl.java:144) ~[classes/:na]
	at com.kang.javassist.controller.JavassistController.addMethodByJavassist(JavassistController.java:60) ~[classes/:na]
	at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:104) ~[na:na]
	at java.base/java.lang.reflect.Method.invoke(Method.java:577) ~[na:na]
	at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205) ~[spring-web-5.3.20.jar:5.3.20]
	at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:150) ~[spring-web-5.3.20.jar:5.3.20]
	at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:117) ~[spring-webmvc-5.3.20.jar:5.3.20]
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895) ~[spring-webmvc-5.3.20.jar:5.3.20]
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:808) ~[spring-webmvc-5.3.20.jar:5.3.20]
	at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-5.3.20.jar:5.3.20]
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1067) ~[spring-webmvc-5.3.20.jar:5.3.20]
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:963) ~[spring-webmvc-5.3.20.jar:5.3.20]
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) ~[spring-webmvc-5.3.20.jar:5.3.20]
	at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:909) ~[spring-webmvc-5.3.20.jar:5.3.20]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:681) ~[tomcat-embed-core-9.0.63.jar:4.0.FR]
	at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) ~[spring-webmvc-5.3.20.jar:5.3.20]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:764) ~[tomcat-embed-core-9.0.63.jar:4.0.FR]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ~[tomcat-embed-websocket-9.0.63.jar:9.0.63]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) ~[spring-web-5.3.20.jar:5.3.20]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.20.jar:5.3.20]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) ~[spring-web-5.3.20.jar:5.3.20]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.20.jar:5.3.20]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) ~[spring-web-5.3.20.jar:5.3.20]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.20.jar:5.3.20]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:197) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:135) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:360) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:399) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:890) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1743) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) ~[tomcat-embed-core-9.0.63.jar:9.0.63]
	at java.base/java.lang.Thread.run(Thread.java:833) ~[na:na]

3.解决方案IDEA添加配置

 结果

问题完美解决