Activiti: why was "commandExecutor" Properties always threw an exception ("NullpointException") ？

com.alibaba.dubbo.common.bytecode.proxy1@759f72d32018-07-30 11:48:39,711 [qtp1194385648-18] ERROR [com.gw.oydCloud.common.base.BaseController] - 统一异常处理： java.lang.NullPointerException at org.activiti.engine.impl.DeploymentQueryImpl.executeCount(DeploymentQueryImpl.java:157) at org.activiti.engine.impl.AbstractQuery.count(AbstractQuery.java:159) at com.gw.oydCloud.upms.server.controller.manage.UpmsDeployController.list(UpmsDeployController.java:54) at com.gw.oydCloud.upms.server.controller.manage.UpmsDeployController$$FastClassBySpringCGLIB$$6472e0db.invoke(<generated>) at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204) at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:721) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157) at org.springframework.aop.framework.adapter.MethodBeforeAdviceInterceptor.invoke(MethodBeforeAdviceInterceptor.java:52) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) at org.springframework.aop.aspectj.MethodInvocationProceedingJoinPoint.proceed(MethodInvocationProceedingJoinPoint.java:85) at com.gw.oydCloud.upms.client.interceptor.LogAspect.doAround(LogAspect.java:64) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethodWithGivenArgs(AbstractAspectJAdvice.java:629) at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethod(AbstractAspectJAdvice.java:618) at org.springframework.aop.aspectj.AspectJAroundAdvice.invoke(AspectJAroundAdvice.java:70) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) at org.springframework.aop.aspectj.AspectJAfterAdvice.invoke(AspectJAfterAdvice.java:47) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) at org.apache.shiro.spring.security.interceptor.AopAllianceAnnotationsAuthorizingMethodInterceptor$1.proceed(AopAllianceAnnotationsAuthorizingMethodInterceptor.java:82) at org.apache.shiro.authz.aop.AuthorizingMethodInterceptor.invoke(AuthorizingMethodInterceptor.java:39) at org.apache.shiro.spring.security.interceptor.AopAllianceAnnotationsAuthorizingMethodInterceptor.invoke(AopAllianceAnnotationsAuthorizingMethodInterceptor.java:115) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:656) at com.gw.oydCloud.upms.server.controller.manage.UpmsDeployController$$EnhancerBySpringCGLIB$$8501a9b6.list(<generated>) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205) at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:133) at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:116) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738) at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:963) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:897) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970) at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:861) at javax.servlet.http.HttpServlet.service(HttpServlet.java:687) at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846) at javax.servlet.http.HttpServlet.service(HttpServlet.java:790) at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:800) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1669) at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:61) at org.apache.shiro.web.servlet.AdviceFilter.executeChain(AdviceFilter.java:108) at org.apache.shiro.web.servlet.AdviceFilter.doFilterInternal(AdviceFilter.java:137) at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125) at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:66) at org.apache.shiro.web.servlet.AdviceFilter.executeChain(AdviceFilter.java:108) at org.apache.shiro.web.servlet.AdviceFilter.doFilterInternal(AdviceFilter.java:137) at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125) at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:66) at org.apache.shiro.web.servlet.AbstractShiroFilter.executeChain(AbstractShiroFilter.java:449) at org.apache.shiro.web.servlet.AbstractShiroFilter$1.call(AbstractShiroFilter.java:365) at org.apache.shiro.subject.support.SubjectCallable.doCall(SubjectCallable.java:90) at org.apache.shiro.subject.support.SubjectCallable.call(SubjectCallable.java:83) at org.apache.shiro.subject.support.DelegatingSubject.execute(DelegatingSubject.java:383) at org.apache.shiro.web.servlet.AbstractShiroFilter.doFilterInternal(AbstractShiroFilter.java:362) at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125) at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346) at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:262) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1652) at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1652) at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:585) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143) at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:577) at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:223) at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1127) at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:515) at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185) at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1061) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141) at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:215) at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:110) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97) at org.eclipse.jetty.server.Server.handle(Server.java:497) at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:310) at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:245) at org.eclipse.jetty.io.AbstractConnection$2.run(AbstractConnection.java:540) at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:635) at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:555) at java.lang.Thread.run(Thread.java:745)

@daisuke-yoshimoto

@zhaogituser Also, if you want to use activiti-context.xml, you should set so that dubbo-provider.xml refer activiti-context.xml. For example, the following.

<import resource="classpath:activiti-context.xml"/>

@zhaogituser

Sorry I made you wait. I have been busy with my full time job for a while.

<dubbo:service interface="org.activiti.engine.RuntimeService" ref="runtimeService" timeout="10000"/>

This mean that Spring framework uses runtimeService as the implementation of the interface org.activiti.engine.RuntimeService.

<bean id="runtimeService" class="org.activiti.engine.impl.RuntimeServiceImpl"/>

And, runtimeService mean new org.activiti.engine.impl.RuntimeServiceImpl();

So, dubbo use new org.activiti.engine.impl.RuntimeServiceImpl() as the implementation of the interface org.activiti.engine.RuntimeService.

@zhaogituser

Sorry I made you wait. After all, I could not confirm the reproducibility in your project, but I understood what seemed to be the cause. When checking applicationContext-dubbo-provider.xml, RepositoryService’s bean was not retrieved from processEngine. RepositoryService’s bean was directly created from new RuntimeServiceImpl(). So, if you use RepositoryService’s bean, its bean cannot access processEngine and cannot get commandExecutor.

Please check examples for spring bean setting. https://github.com/Activiti/Activiti/blob/5.19.0.2/modules/activiti-spring/src/test/resources/activiti-context.xml#L45

applicationContext-dubbo-provider.xml

<!--activity-->
<bean id="runtimeService" class="org.activiti.engine.impl.RuntimeServiceImpl"/>
<dubbo:service interface="org.activiti.engine.RuntimeService" ref="runtimeService" timeout="10000"/>

<bean id="repositoryService" class="org.activiti.engine.impl.RepositoryServiceImpl"/>
<dubbo:service interface="org.activiti.engine.RepositoryService" ref="repositoryService" timeout="10000"/>

<bean id="taskService" class="org.activiti.engine.impl.TaskServiceImpl"/>
<dubbo:service interface="org.activiti.engine.TaskService" ref="taskService" timeout="10000"/>

<bean id="historyService" class="org.activiti.engine.impl.HistoryServiceImpl"/>
<dubbo:service interface="org.activiti.engine.HistoryService" ref="historyService" timeout="10000"/>

<bean id="managementService" class="org.activiti.engine.impl.ManagementServiceImpl"/>
<dubbo:service interface="org.activiti.engine.ManagementService"  ref="managementService" timeout="10000"/>

<bean id="identityService" class="org.activiti.engine.impl.IdentityServiceImpl"/>
<dubbo:service interface="org.activiti.engine.IdentityService" ref="identityService" timeout="10000"/>

<bean id="formService"  class="org.activiti.engine.impl.FormServiceImpl"/>
<dubbo:service interface="org.activiti.engine.FormService" ref="formService" timeout="100000"/>

@zhaogituser Ohh, do you mean that you want to share your real project to only me? Not public? If so, please share its url to https://twitter.com/daisuke_yoshimo by direct message.

@zhaogituser Good. If you can use google drive, you can upload your project and share its url to me in this thread.

@daisuke-yoshimoto I just had a google driver account. I will upload my source code to google driver, tomorrow morning. Would you like to share the link with me or if you give me the gmail email address?

Thank you again for your help.

@zhaogituser Please upload the full stacktrace of your NullpointException.

@zhaogituser it’s a property of the process engine configuration should be in activiti-context.xml for the processEngineConfiguration.