NPE in Groovydoc

[ant:groovydoc] java.lang.NullPointerException
[ant:groovydoc] 	at org.codehaus.groovy.tools.groovydoc.SimpleGroovyRootDoc.classNamed(SimpleGroovyRootDoc.java:48)
[ant:groovydoc] 	at org.codehaus.groovy.tools.groovydoc.SimpleGroovyClassDoc.getDocUrl(SimpleGroovyClassDoc.java:442)
[ant:groovydoc] 	at org.codehaus.groovy.tools.groovydoc.SimpleGroovyClassDoc.replaceAllTags(SimpleGroovyClassDoc.java:767)
[ant:groovydoc] 	at org.codehaus.groovy.tools.groovydoc.GroovyRootDocBuilder.replaceAllTags(GroovyRootDocBuilder.java:275)
[ant:groovydoc] 	at org.codehaus.groovy.tools.groovydoc.GroovyRootDocBuilder.replaceTags(GroovyRootDocBuilder.java:261)
[ant:groovydoc] 	at org.codehaus.groovy.tools.groovydoc.GroovyRootDocBuilder.calcThenSetPackageDescription(GroovyRootDocBuilder.java:252)
[ant:groovydoc] 	at org.codehaus.groovy.tools.groovydoc.GroovyRootDocBuilder.processPackageInfo(GroovyRootDocBuilder.java:236)
[ant:groovydoc] 	at org.codehaus.groovy.tools.groovydoc.GroovyRootDocBuilder.processFile(GroovyRootDocBuilder.java:203)
[ant:groovydoc] 	at org.codehaus.groovy.tools.groovydoc.GroovyRootDocBuilder.buildTree(GroovyRootDocBuilder.java:171)
[ant:groovydoc] 	at org.codehaus.groovy.tools.groovydoc.GroovyDocTool.add(GroovyDocTool.java:70)
[ant:groovydoc] 	at org.codehaus.groovy.ant.Groovydoc.execute(Groovydoc.java:429)
[ant:groovydoc] 	at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:291)
[ant:groovydoc] 	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
[ant:groovydoc] 	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
[ant:groovydoc] 	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
[ant:groovydoc] 	at java.lang.reflect.Method.invoke(Method.java:601)
[ant:groovydoc] 	at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
[ant:groovydoc] 	at groovy.util.AntBuilder.performTask(AntBuilder.java:260)
[ant:groovydoc] 	at groovy.util.AntBuilder.nodeCompleted(AntBuilder.java:220)
[ant:groovydoc] 	at org.gradle.api.internal.project.ant.BasicAntBuilder.nodeCompleted(BasicAntBuilder.java:71)
[ant:groovydoc] 	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
[ant:groovydoc] 	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
[ant:groovydoc] 	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
[ant:groovydoc] 	at java.lang.reflect.Method.invoke(Method.java:601)
[ant:groovydoc] 	at org.codehaus.groovy.runtime.callsite.PojoMetaMethodSite$PojoCachedMethodSiteNoUnwrapNoCoerce.invoke(PojoMetaMethodSite.java:230)
[ant:groovydoc] 	at org.codehaus.groovy.runtime.callsite.PojoMetaMethodSite.call(PojoMetaMethodSite.java:53)
[ant:groovydoc] 	at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:42)
[ant:groovydoc] 	at org.codehaus.groovy.runtime.callsite.PojoMetaMethodSite.call(PojoMetaMethodSite.java:55)
[ant:groovydoc] 	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:120)
[ant:groovydoc] 	at org.gradle.api.internal.project.AntBuilderDelegate.nodeCompleted(DefaultIsolatedAntBuilder.groovy:172)
[ant:groovydoc] 	at groovy.util.BuilderSupport.doInvokeMethod(BuilderSupport.java:147)
[ant:groovydoc] 	at groovy.util.BuilderSupport.invokeMethod(BuilderSupport.java:64)
[ant:groovydoc] 	at org.codehaus.groovy.runtime.metaclass.ClosureMetaClass.invokeOnDelegationObjects(ClosureMetaClass.java:407)
[ant:groovydoc] 	at org.codehaus.groovy.runtime.metaclass.ClosureMetaClass.invokeMethod(ClosureMetaClass.java:348)
[ant:groovydoc] 	at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:877)
[ant:groovydoc] 	at org.codehaus.groovy.runtime.callsite.PogoMetaClassSite.callCurrent(PogoMetaClassSite.java:66)
[ant:groovydoc] 	at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCallCurrent(CallSiteArray.java:46)
[ant:groovydoc] 	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callCurrent(AbstractCallSite.java:133)
[ant:groovydoc] 	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callCurrent(AbstractCallSite.java:145)
[ant:groovydoc] 	at org.gradle.api.tasks.javadoc.AntGroovydoc$_execute_closure2.doCall(AntGroovydoc.groovy:60)
[ant:groovydoc] 	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
[ant:groovydoc] 	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
[ant:groovydoc] 	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
[ant:groovydoc] 	at java.lang.reflect.Method.invoke(Method.java:601)
[ant:groovydoc] 	at org.codehaus.groovy.reflection.CachedMethod.invoke(CachedMethod.java:90)
[ant:groovydoc] 	at groovy.lang.MetaMethod.doMethodInvoke(MetaMethod.java:233)
[ant:groovydoc] 	at org.codehaus.groovy.runtime.metaclass.ClosureMetaClass.invokeMethod(ClosureMetaClass.java:272)
[ant:groovydoc] 	at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:877)
[ant:groovydoc] 	at groovy.lang.Closure.call(Closure.java:412)
[ant:groovydoc] 	at groovy.lang.Closure.call(Closure.java:425)
[ant:groovydoc] 	at org.gradle.api.internal.ClosureBackedAction.execute(ClosureBackedAction.java:58)
[ant:groovydoc] 	at org.gradle.util.ConfigureUtil.configure(ConfigureUtil.java:133)
[ant:groovydoc] 	at org.gradle.util.ConfigureUtil.configure(ConfigureUtil.java:94)
[ant:groovydoc] 	at org.gradle.util.ConfigureUtil$configure.call(Unknown Source)
[ant:groovydoc] 	at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:42)
[ant:groovydoc] 	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:108)
[ant:groovydoc] 	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:120)
[ant:groovydoc] 	at org.gradle.api.internal.project.DefaultIsolatedAntBuilder.execute(DefaultIsolatedAntBuilder.groovy:112)
[ant:groovydoc] 	at org.gradle.api.internal.project.IsolatedAntBuilder$execute.call(Unknown Source)
[ant:groovydoc] 	at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:42)
[ant:groovydoc] 	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:108)
[ant:groovydoc] 	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:116)
[ant:groovydoc] 	at org.gradle.api.tasks.javadoc.AntGroovydoc.execute(AntGroovydoc.groovy:58)
[ant:groovydoc] 	at org.gradle.api.tasks.javadoc.Groovydoc.generate(Groovydoc.java:75)
[ant:groovydoc] 	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
[ant:groovydoc] 	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
[ant:groovydoc] 	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
[ant:groovydoc] 	at java.lang.reflect.Method.invoke(Method.java:601)
[ant:groovydoc] 	at org.codehaus.groovy.reflection.CachedMethod.invoke(CachedMethod.java:90)
[ant:groovydoc] 	at groovy.lang.MetaMethod.doMethodInvoke(MetaMethod.java:233)
[ant:groovydoc] 	at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:1047)
[ant:groovydoc] 	at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:877)
[ant:groovydoc] 	at org.gradle.api.internal.BeanDynamicObject$MetaClassAdapter.invokeMethod(BeanDynamicObject.java:216)
[ant:groovydoc] 	at org.gradle.api.internal.BeanDynamicObject.invokeMethod(BeanDynamicObject.java:122)
[ant:groovydoc] 	at org.gradle.api.internal.CompositeDynamicObject.invokeMethod(CompositeDynamicObject.java:147)
[ant:groovydoc] 	at org.gradle.api.tasks.javadoc.Groovydoc_Decorated.invokeMethod(Unknown Source)
[ant:groovydoc] 	at groovy.lang.GroovyObject$invokeMethod.call(Unknown Source)
[ant:groovydoc] 	at org.gradle.util.ReflectionUtil.invoke(ReflectionUtil.groovy:23)
[ant:groovydoc] 	at org.gradle.api.internal.project.taskfactory.AnnotationProcessingTaskFactory$4.execute(AnnotationProcessingTaskFactory.java:161)
[ant:groovydoc] 	at org.gradle.api.internal.project.taskfactory.AnnotationProcessingTaskFactory$4.execute(AnnotationProcessingTaskFactory.java:156)
[ant:groovydoc] 	at org.gradle.api.internal.AbstractTask$TaskActionWrapper.execute(AbstractTask.java:510)
[ant:groovydoc] 	at org.gradle.api.internal.AbstractTask$TaskActionWrapper.execute(AbstractTask.java:499)
[ant:groovydoc] 	at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:64)
[ant:groovydoc] 	at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:49)
[ant:groovydoc] 	at org.gradle.api.internal.tasks.execution.PostExecutionAnalysisTaskExecuter.execute(PostExecutionAnalysisTaskExecuter.java:34)
[ant:groovydoc] 	at org.gradle.api.internal.changedetection.CacheLockHandlingTaskExecuter$1.run(CacheLockHandlingTaskExecuter.java:34)
[ant:groovydoc] 	at org.gradle.internal.Factories$1.create(Factories.java:22)
[ant:groovydoc] 	at org.gradle.cache.internal.DefaultCacheAccess.longRunningOperation(DefaultCacheAccess.java:179)
[ant:groovydoc] 	at org.gradle.cache.internal.DefaultCacheAccess.longRunningOperation(DefaultCacheAccess.java:232)
[ant:groovydoc] 	at org.gradle.cache.internal.DefaultPersistentDirectoryStore.longRunningOperation(DefaultPersistentDirectoryStore.java:142)
[ant:groovydoc] 	at org.gradle.api.internal.changedetection.DefaultTaskArtifactStateCacheAccess.longRunningOperation(DefaultTaskArtifactStateCacheAccess.java:83)
[ant:groovydoc] 	at org.gradle.api.internal.changedetection.CacheLockHandlingTaskExecuter.execute(CacheLockHandlingTaskExecuter.java:32)
[ant:groovydoc] 	at org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute(SkipUpToDateTaskExecuter.java:55)
[ant:groovydoc] 	at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:57)
[ant:groovydoc] 	at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:41)
[ant:groovydoc] 	at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:51)
[ant:groovydoc] 	at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:52)
[ant:groovydoc] 	at org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter.execute(ExecuteAtMostOnceTaskExecuter.java:42)
[ant:groovydoc] 	at org.gradle.api.internal.AbstractTask.executeWithoutThrowingTaskFailure(AbstractTask.java:275)
[ant:groovydoc] 	at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor.executeTask(DefaultTaskPlanExecutor.java:52)
[ant:groovydoc] 	at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor.processTask(DefaultTaskPlanExecutor.java:38)
[ant:groovydoc] 	at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor.process(DefaultTaskPlanExecutor.java:30)
[ant:groovydoc] 	at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter.execute(DefaultTaskGraphExecuter.java:84)
[ant:groovydoc] 	at org.gradle.execution.SelectedTaskExecutionAction.execute(SelectedTaskExecutionAction.java:29)
[ant:groovydoc] 	at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:61)
[ant:groovydoc] 	at org.gradle.execution.DefaultBuildExecuter.access$200(DefaultBuildExecuter.java:23)
[ant:groovydoc] 	at org.gradle.execution.DefaultBuildExecuter$2.proceed(DefaultBuildExecuter.java:67)
[ant:groovydoc] 	at org.gradle.api.internal.changedetection.TaskCacheLockHandlingBuildExecuter$1.run(TaskCacheLockHandlingBuildExecuter.java:31)
[ant:groovydoc] 	at org.gradle.internal.Factories$1.create(Factories.java:22)
[ant:groovydoc] 	at org.gradle.cache.internal.DefaultCacheAccess.useCache(DefaultCacheAccess.java:124)
[ant:groovydoc] 	at org.gradle.cache.internal.DefaultCacheAccess.useCache(DefaultCacheAccess.java:112)
[ant:groovydoc] 	at org.gradle.cache.internal.DefaultPersistentDirectoryStore.useCache(DefaultPersistentDirectoryStore.java:134)
[ant:groovydoc] 	at org.gradle.api.internal.changedetection.DefaultTaskArtifactStateCacheAccess.useCache(DefaultTaskArtifactStateCacheAccess.java:79)
[ant:groovydoc] 	at org.gradle.api.internal.changedetection.TaskCacheLockHandlingBuildExecuter.execute(TaskCacheLockHandlingBuildExecuter.java:29)
[ant:groovydoc] 	at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:61)
[ant:groovydoc] 	at org.gradle.execution.DefaultBuildExecuter.access$200(DefaultBuildExecuter.java:23)
[ant:groovydoc] 	at org.gradle.execution.DefaultBuildExecuter$2.proceed(DefaultBuildExecuter.java:67)
[ant:groovydoc] 	at org.gradle.execution.DryRunBuildExecutionAction.execute(DryRunBuildExecutionAction.java:32)
[ant:groovydoc] 	at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:61)
[ant:groovydoc] 	at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:54)
[ant:groovydoc] 	at org.gradle.initialization.DefaultGradleLauncher.doBuildStages(DefaultGradleLauncher.java:165)
[ant:groovydoc] 	at org.gradle.initialization.DefaultGradleLauncher.doBuild(DefaultGradleLauncher.java:113)
[ant:groovydoc] 	at org.gradle.initialization.DefaultGradleLauncher.run(DefaultGradleLauncher.java:81)
[ant:groovydoc] 	at org.gradle.launcher.cli.ExecuteBuildAction.run(ExecuteBuildAction.java:38)
[ant:groovydoc] 	at org.gradle.launcher.exec.InProcessGradleLauncherActionExecuter.execute(InProcessGradleLauncherActionExecuter.java:39)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.ExecuteBuild.doBuild(ExecuteBuild.java:45)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:34)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.DaemonCommandExecution.proceed(DaemonCommandExecution.java:126)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.WatchForDisconnection.execute(WatchForDisconnection.java:42)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.DaemonCommandExecution.proceed(DaemonCommandExecution.java:126)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.ResetDeprecationLogger.execute(ResetDeprecationLogger.java:24)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.DaemonCommandExecution.proceed(DaemonCommandExecution.java:126)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.StartStopIfBuildAndStop.execute(StartStopIfBuildAndStop.java:33)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.DaemonCommandExecution.proceed(DaemonCommandExecution.java:126)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.ReturnResult.execute(ReturnResult.java:34)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.DaemonCommandExecution.proceed(DaemonCommandExecution.java:126)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.ForwardClientInput$2.call(ForwardClientInput.java:70)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.ForwardClientInput$2.call(ForwardClientInput.java:68)
[ant:groovydoc] 	at org.gradle.util.Swapper.swap(Swapper.java:38)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.ForwardClientInput.execute(ForwardClientInput.java:68)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.DaemonCommandExecution.proceed(DaemonCommandExecution.java:126)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.LogToClient.doBuild(LogToClient.java:60)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:34)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.DaemonCommandExecution.proceed(DaemonCommandExecution.java:126)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.EstablishBuildEnvironment.doBuild(EstablishBuildEnvironment.java:59)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:34)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.DaemonCommandExecution.proceed(DaemonCommandExecution.java:126)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.StartBuildOrRespondWithBusy$1.run(StartBuildOrRespondWithBusy.java:45)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.DaemonStateCoordinator.runCommand(DaemonStateCoordinator.java:186)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.StartBuildOrRespondWithBusy.doBuild(StartBuildOrRespondWithBusy.java:49)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:34)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.DaemonCommandExecution.proceed(DaemonCommandExecution.java:126)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.HandleStop.execute(HandleStop.java:36)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.DaemonCommandExecution.proceed(DaemonCommandExecution.java:126)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.CatchAndForwardDaemonFailure.execute(CatchAndForwardDaemonFailure.java:32)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.DaemonCommandExecution.proceed(DaemonCommandExecution.java:126)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.exec.DefaultDaemonCommandExecuter.executeCommand(DefaultDaemonCommandExecuter.java:48)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.DefaultIncomingConnectionHandler$ConnectionWorker.handleCommand(DefaultIncomingConnectionHandler.java:155)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.DefaultIncomingConnectionHandler$ConnectionWorker.receiveAndHandleCommand(DefaultIncomingConnectionHandler.java:128)
[ant:groovydoc] 	at org.gradle.launcher.daemon.server.DefaultIncomingConnectionHandler$ConnectionWorker.run(DefaultIncomingConnectionHandler.java:116)
[ant:groovydoc] 	at org.gradle.internal.concurrent.DefaultExecutorFactory$StoppableExecutorImpl$1.run(DefaultExecutorFactory.java:66)
[ant:groovydoc] 	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
[ant:groovydoc] 	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
[ant:groovydoc] 	at java.lang.Thread.run(Thread.java:722)