javafx-gradle-plugin: Gradle 3.3 support missing

Any gradle commands in a project with javafx-gradle-plugin defined as a buildscript dependency fails. Even gradle tasks.

The stacktrace suggests the culprit is this plugin (plus other projects that don’t use it are building fine):

(Whole stacktrace included for completionism’s sake, but pretty sure only the bottom “Caused by” is relevant.)

23:05 $ gradle --stacktrace clean

FAILURE: Build failed with an exception.

* What went wrong:
A problem occurred configuring root project 'Joyce'.
> Failed to notify project evaluation listener.
   > org.gradle.internal.classloader.ClasspathUtil.getClasspath(Ljava/lang/ClassLoader;)Ljava/util/List;

* Try:
Run with --info or --debug option to get more log output.

* Exception is:
org.gradle.api.ProjectConfigurationException: A problem occurred configuring root project 'Joyce'.
        at org.gradle.configuration.project.LifecycleProjectEvaluator.addConfigurationFailure(LifecycleProjectEvaluator.java:94)
        at org.gradle.configuration.project.LifecycleProjectEvaluator.notifyAfterEvaluate(LifecycleProjectEvaluator.java:89)
        at org.gradle.configuration.project.LifecycleProjectEvaluator.doConfigure(LifecycleProjectEvaluator.java:76)
        at org.gradle.configuration.project.LifecycleProjectEvaluator.access$000(LifecycleProjectEvaluator.java:33)
        at org.gradle.configuration.project.LifecycleProjectEvaluator$1.execute(LifecycleProjectEvaluator.java:53)
        at org.gradle.configuration.project.LifecycleProjectEvaluator$1.execute(LifecycleProjectEvaluator.java:50)
        at org.gradle.internal.Transformers$4.transform(Transformers.java:169)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:106)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:61)
        at org.gradle.configuration.project.LifecycleProjectEvaluator.evaluate(LifecycleProjectEvaluator.java:50)
        at org.gradle.api.internal.project.DefaultProject.evaluate(DefaultProject.java:628)
        at org.gradle.api.internal.project.DefaultProject.evaluate(DefaultProject.java:129)
        at org.gradle.execution.TaskPathProjectEvaluator.configure(TaskPathProjectEvaluator.java:35)
        at org.gradle.execution.TaskPathProjectEvaluator.configureHierarchy(TaskPathProjectEvaluator.java:60)
        at org.gradle.configuration.DefaultBuildConfigurer.configure(DefaultBuildConfigurer.java:38)
        at org.gradle.initialization.DefaultGradleLauncher$1.execute(DefaultGradleLauncher.java:161)
        at org.gradle.initialization.DefaultGradleLauncher$1.execute(DefaultGradleLauncher.java:158)
        at org.gradle.internal.Transformers$4.transform(Transformers.java:169)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:106)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:56)
        at org.gradle.initialization.DefaultGradleLauncher.doBuildStages(DefaultGradleLauncher.java:158)
        at org.gradle.initialization.DefaultGradleLauncher.doBuild(DefaultGradleLauncher.java:119)
        at org.gradle.initialization.DefaultGradleLauncher.run(DefaultGradleLauncher.java:102)
        at org.gradle.launcher.exec.GradleBuildController.run(GradleBuildController.java:71)
        at org.gradle.tooling.internal.provider.ExecuteBuildActionRunner.run(ExecuteBuildActionRunner.java:28)
        at org.gradle.launcher.exec.ChainingBuildActionRunner.run(ChainingBuildActionRunner.java:35)
        at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:41)
        at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:26)
        at org.gradle.tooling.internal.provider.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:75)
        at org.gradle.tooling.internal.provider.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:49)
        at org.gradle.tooling.internal.provider.ServicesSetupBuildActionExecuter.execute(ServicesSetupBuildActionExecuter.java:44)
        at org.gradle.tooling.internal.provider.ServicesSetupBuildActionExecuter.execute(ServicesSetupBuildActionExecuter.java:29)
        at org.gradle.launcher.daemon.server.exec.ExecuteBuild.doBuild(ExecuteBuild.java:67)
        at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.WatchForDisconnection.execute(WatchForDisconnection.java:47)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.ResetDeprecationLogger.execute(ResetDeprecationLogger.java:26)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.RequestStopIfSingleUsedDaemon.execute(RequestStopIfSingleUsedDaemon.java:34)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.ForwardClientInput$2.call(ForwardClientInput.java:74)
        at org.gradle.launcher.daemon.server.exec.ForwardClientInput$2.call(ForwardClientInput.java:72)
        at org.gradle.util.Swapper.swap(Swapper.java:38)
        at org.gradle.launcher.daemon.server.exec.ForwardClientInput.execute(ForwardClientInput.java:72)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.LogAndCheckHealth.execute(LogAndCheckHealth.java:55)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.LogToClient.doBuild(LogToClient.java:60)
        at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.EstablishBuildEnvironment.doBuild(EstablishBuildEnvironment.java:72)
        at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.StartBuildOrRespondWithBusy$1.run(StartBuildOrRespondWithBusy.java:50)
        at org.gradle.launcher.daemon.server.DaemonStateCoordinator$1.run(DaemonStateCoordinator.java:297)
        at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:54)
        at org.gradle.internal.concurrent.StoppableExecutorImpl$1.run(StoppableExecutorImpl.java:40)
Caused by: org.gradle.internal.event.ListenerNotificationException: Failed to notify project evaluation listener.
        at org.gradle.internal.event.AbstractBroadcastDispatch.dispatch(AbstractBroadcastDispatch.java:55)
        at org.gradle.internal.event.BroadcastDispatch.dispatch(BroadcastDispatch.java:79)
        at org.gradle.internal.event.BroadcastDispatch.dispatch(BroadcastDispatch.java:30)
        at org.gradle.internal.dispatch.ProxyDispatchAdapter$DispatchingInvocationHandler.invoke(ProxyDispatchAdapter.java:93)
        at com.sun.proxy.$Proxy16.afterEvaluate(Unknown Source)
        at org.gradle.configuration.project.LifecycleProjectEvaluator.notifyAfterEvaluate(LifecycleProjectEvaluator.java:82)
        ... 56 more
Caused by: java.lang.NoSuchMethodError: org.gradle.internal.classloader.ClasspathUtil.getClasspath(Ljava/lang/ClassLoader;)Ljava/util/List;
        at de.dynamicfiles.projects.gradle.plugins.javafx.JavaFXGradlePlugin.addJavaFXAntJARToGradleBuildpath(JavaFXGradlePlugin.java:142)
        at de.dynamicfiles.projects.gradle.plugins.javafx.JavaFXGradlePlugin.lambda$apply$0(JavaFXGradlePlugin.java:94)
        at org.gradle.internal.event.BroadcastDispatch$ActionInvocationHandler.dispatch(BroadcastDispatch.java:93)
        at org.gradle.internal.event.BroadcastDispatch$ActionInvocationHandler.dispatch(BroadcastDispatch.java:82)
        at org.gradle.internal.event.AbstractBroadcastDispatch.dispatch(AbstractBroadcastDispatch.java:44)
        ... 61 more


BUILD FAILED

Total time: 1.12 secs