Accessing a Service Builder module from a Spring MVC portlet in Liferay DXP

Issue

• When a Spring MVC portlet is trying to call a Service Builder service, there are java.lang.ClassCastExceptions in the logs. For example:

ERROR [http-nio-8080-exec-5][DispatcherPortlet:428] Could not complete request
java.lang.ClassCastException: com.sun.proxy.$Proxy1205 cannot be cast to sample.service.service.SampleLocalService
at sample.service.service.SampleLocalServiceUtil.getService(SampleLocalServiceUtil.java:367)
at sample.service.service.SampleLocalServiceUtil.getSamplesCount(SampleLocalServiceUtil.java:347)
at sample.springmvc.portlet1.controller.UserController.submitApplicant(UserController.java:91)
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:497)
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138)
at com.liferay.portletmvc4spring.mvc.method.annotation.PortletInvocableHandlerMethod.invokeAndHandle(PortletInvocableHandlerMethod.java:100)
at com.liferay.portletmvc4spring.mvc.method.annotation.PortletRequestMappingHandlerAdapter.invokeHandlerMethod(PortletRequestMappingHandlerAdapter.java:1042)
at com.liferay.portletmvc4spring.mvc.method.annotation.PortletRequestMappingHandlerAdapter.doHandle(PortletRequestMappingHandlerAdapter.java:586)
at com.liferay.portletmvc4spring.mvc.method.annotation.PortletRequestMappingHandlerAdapter.doHandle(PortletRequestMappingHandlerAdapter.java:535)
at com.liferay.portletmvc4spring.mvc.method.annotation.PortletRequestMappingHandlerAdapter.handleActionInternal(PortletRequestMappingHandlerAdapter.java:601)
at com.liferay.portletmvc4spring.mvc.method.AbstractPortletHandlerMethodAdapter.handleAction(AbstractPortletHandlerMethodAdapter.java:55)
at com.liferay.portletmvc4spring.DispatcherPortlet.doActionService(DispatcherPortlet.java:462)
at com.liferay.portletmvc4spring.FrameworkPortlet.processRequest(FrameworkPortlet.java:692)
at com.liferay.portletmvc4spring.FrameworkPortlet.processAction(FrameworkPortlet.java:232)
...

Environment

• DXP 7.0+

Resolution

• In this case, the Service Builder module's API is added as a dependency in the Spring MVC Portlet which makes the API's jar to be included in the built WAR's WEB-INF/lib folder and this results in the above error.
• In order to make sure that the jar is not included in the WAR itself, the following property should be added to the portal-ext.properties file:

module.framework.web.generator.excluded.paths=<CURRENT EXCLUSIONS>,\
  WEB-INF/lib/{api-jar}

• Where {api-jar} is your Service Builder module's API jar.
• When the WAR->WAB conversion is taking place, it will exclude the API jar from being included.
• Important: Remember to keep all of the currently excluded paths in the list, you can find them in the portal.properties file included in your Liferay bundle.

Additional Information

• The community blog post which includes the above information: Service Builder 6.2 Migration