I am using Grails 6 to generate an API service. Im running into an issue when I use views to expose data. I am using Controllers that extend from RestfulController, I have simple Domain objects with limited properties and a couple of relationships. The issue arises when I have Domain classes that use CamelCase such as ClinicalCenter or MolecularMarker. Using names such as Patient is no problem. Taking the latter case; I would have a folder called patient and therein a file called _patient.gson to show the data, works as expected. Taking the first example, I would have a view folder called molecularMarker and therin a file called _molecularMarker.gson, with almost the same data as patient but I keep getting the error below. I have tried other names, such as ClinicalCenter, and all give a similar error. If I were just to use Clinic then that does work. Am I missing something that I should be configuring/setting/naming? Here is an example of the template with the error below: model { MolecularMarker marker } json { id marker.id description marker.name } 2025-07-11 105433.970 ERROR --- [nio-8080-exec-1] .a.c.c.C.[.[.[.[grailsDispatcherServlet] : Servlet.service() for servlet [grailsDispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is grails.views.ViewRenderException: Error rendering view: Error rendering view: Cannot get property 'id' on null object] with root cause java.lang.NullPointerException: Cannot get property 'id' on null object at org.codehaus.groovy.runtime.NullObject.getProperty(NullObject.java:89) at org.codehaus.groovy.runtime.InvokerHelper.getProperty(InvokerHelper.java:190) at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callGroovyObjectGetProperty(AbstractCallSite.java:336) at oncode_api_molecularMarker__molecularMarker_gson$_run_closure1.doCall(oncode_api_molecularMarker__molecularMarker_gson:8) at oncode_api_molecularMarker__molecularMarker_gson$_run_closure1.call(oncode_api_molecularMarker__molecularMarker_gson) at grails.plugin.json.builder.StreamingJsonBuilder$StreamingJsonDelegate.cloneDelegateAndGetContent(StreamingJsonBuilder.java:836) at grails.plugin.json.builder.StreamingJsonBuilder.call(StreamingJsonBuilder.java:255) at grails.plugin.json.view.JsonViewWritableScript.json(JsonViewWritableScript.groovy:81) at oncode_api_molecularMarker__molecularMarker_gson.run(oncode_api_molecularMarker__molecularMarker_gson:7) at grails.plugin.json.view.JsonViewWritableScript.doWrite(JsonViewWritableScript.groovy:29) at grails.views.AbstractWritableScript.writeTo(AbstractWritableScript.groovy:40) at grails.plugin.json.view.api.internal.DefaultGrailsJsonViewHelper$5.writeTo(DefaultGrailsJsonViewHelper.groovy:763) at grails.plugin.json.view.api.internal.DefaultGrailsJsonViewHelper.handleValue(DefaultGrailsJsonViewHelper.groovy:326) at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103) at java.base/java.lang.reflect.Method.invoke(Method.java:580) at org.codehaus.groovy.reflection.CachedMethod.invoke(CachedMethod.java:107) at groovy.lang.MetaMethod.doMethodInvoke(MetaMethod.java:323) at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:1254) at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:1030) at org.codehaus.groovy.runtime.InvokerHelper.invokePogoMethod(InvokerHelper.java:1059) at org.codehaus.groovy.runtime.InvokerHelper.invokeMethod(InvokerHelper.java:1042) at org.codehaus.groovy.runtime.InvokerHelper.invokeMethodSafe(InvokerHelper.java:97) at grails.plugin.json.view.api.internal.DefaultGrailsJsonViewHelper$_getIterableWritable_closure3.doCall(DefaultGrailsJsonViewHelper.groovy:262) at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103) at java.base/java.lang.reflect.Method.invoke(Method.java:580) at org.codehaus.groovy.reflection.CachedMethod.invoke(CachedMethod.java:107) at groovy.lang.MetaMethod.doMethodInvoke(MetaMethod.java:323) at org.codehaus.groovy.runtime.metaclass.ClosureMetaClass.invokeMethod(ClosureMetaClass.java:274) at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:1030) at groovy.lang.Closure.call(Closure.java:427) at grails.plugin.json.view.api.internal.DefaultGrailsJsonViewHelper$2.writeTo(DefaultGrailsJsonViewHelper.groovy:278) at grails.plugin.json.view.JsonViewWritableScript.json(JsonViewWritableScript.groovy:142) at oncode_api_object__object_gson.run(oncode_api_object__object_gson:5) at grails.plugin.json.view.JsonViewWritableScript.doWrite(JsonViewWritableScript.groovy:29) at grails.views.AbstractWritableScript.writeTo(AbstractWritableScript.groovy:40) at grails.views.mvc.GenericGroovyTemplateView.renderMergedOutputModel(GenericGroovyTemplateView.groovy:73) at org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:316) at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1406) at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1150) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1089) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:965) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898) at javax.servlet.http.HttpServlet.service(HttpServlet.java:645) at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) at javax.servlet.http.HttpServlet.service(HttpServlet.java:750) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:209) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:178) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153) at org.grails.web.servlet.mvc.GrailsWebRequestFilter.doFilterInternal(GrailsWebRequestFilter.java:77) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:178) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153) at org.grails.web.filters.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:67) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:178) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153) at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:178) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153) at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.doFilterInternal(WebMvcMetricsFilter.java:96) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:178) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153) at org.springframework.web.filter.CorsFilter.doFilterInternal(CorsFilter.java:91) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:178) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:168) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:90) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:481) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:130) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:93) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342) at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:390) at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:63) at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:928) at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1794) at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:52) at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191) at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.base/java.lang.Thread.run(Thread.java:1583)

or, you can specify the variable name, when you render the template: tmpl.molecularMarker(var: ‘marker’)

Thanks for the tip!