Java 13 Support

[dpeger]

See eclipse-jdtls/eclipse.jdt.ls#1196

Gradle projects can't be build with JDK13 in eclipse 2019-09 (4.13):

java.lang.IllegalArgumentException: Can't convert '13' to enum type 'JavaVersion'
	at org.gradle.tooling.internal.adapter.ProtocolToModelAdapter.adaptToEnum(ProtocolToModelAdapter.java:180)
	at org.gradle.tooling.internal.adapter.ProtocolToModelAdapter.createView(ProtocolToModelAdapter.java:145)
	at org.gradle.tooling.internal.adapter.ProtocolToModelAdapter.convert(ProtocolToModelAdapter.java:204)
	at org.gradle.tooling.internal.adapter.ProtocolToModelAdapter.access$1500(ProtocolToModelAdapter.java:57)
	at org.gradle.tooling.internal.adapter.ProtocolToModelAdapter$AdaptingMethodInvoker.invoke(ProtocolToModelAdapter.java:405)
	at org.gradle.tooling.internal.adapter.ProtocolToModelAdapter$PropertyCachingMethodInvoker.invoke(ProtocolToModelAdapter.java:633)
	at org.gradle.tooling.internal.adapter.ProtocolToModelAdapter$SafeMethodInvoker.invoke(ProtocolToModelAdapter.java:670)
	at org.gradle.tooling.internal.adapter.ProtocolToModelAdapter$SupportedPropertyInvoker.invoke(ProtocolToModelAdapter.java:694)
	at org.gradle.tooling.internal.adapter.ProtocolToModelAdapter$InvocationHandlerImpl.invoke(ProtocolToModelAdapter.java:360)
	at com.sun.proxy.$Proxy44.getSourceLanguageLevel(Unknown Source)
	at org.eclipse.buildship.core.internal.util.gradle.CompatSourceSettings.getSourceLanguageLevel(CompatSourceSettings.java:41)
	at org.eclipse.buildship.core.internal.workspace.JavaSourceSettingsUpdater.update(JavaSourceSettingsUpdater.java:39)
	at org.eclipse.buildship.core.internal.workspace.BaseConfigurator.synchronizeJavaProjectInTransaction(BaseConfigurator.java:118)
	at org.eclipse.buildship.core.internal.workspace.BaseConfigurator.access$000(BaseConfigurator.java:39)
	at org.eclipse.buildship.core.internal.workspace.BaseConfigurator$1.run(BaseConfigurator.java:104)
	at org.eclipse.jdt.internal.core.BatchOperation.executeOperation(BatchOperation.java:41)
	at org.eclipse.jdt.internal.core.JavaModelOperation.run(JavaModelOperation.java:736)
	at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:2295)
	at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:2322)
	at org.eclipse.jdt.core.JavaCore.run(JavaCore.java:5840)
	at org.eclipse.jdt.core.JavaCore.run(JavaCore.java:5797)
	at org.eclipse.buildship.core.internal.workspace.BaseConfigurator.synchronizeJavaProject(BaseConfigurator.java:100)
	at org.eclipse.buildship.core.internal.workspace.BaseConfigurator.configure(BaseConfigurator.java:90)
	at org.eclipse.buildship.core.internal.workspace.BaseConfigurator.configure(BaseConfigurator.java:65)
	at org.eclipse.buildship.core.internal.extension.InternalProjectConfigurator.configure(InternalProjectConfigurator.java:64)
	at org.eclipse.buildship.core.internal.workspace.ProjectConfigurators.configureConfigurators(ProjectConfigurators.java:67)
	at org.eclipse.buildship.core.internal.workspace.SynchronizeGradleBuildOperation.synchronizeOpenWorkspaceProject(SynchronizeGradleBuildOperation.java:166)
	at org.eclipse.buildship.core.internal.workspace.SynchronizeGradleBuildOperation.synchronizeWorkspaceProject(SynchronizeGradleBuildOperation.java:140)
	at org.eclipse.buildship.core.internal.workspace.SynchronizeGradleBuildOperation.synchronizeGradleProjectWithWorkspaceProject(SynchronizeGradleBuildOperation.java:130)
	at org.eclipse.buildship.core.internal.workspace.SynchronizeGradleBuildOperation.access$000(SynchronizeGradleBuildOperation.java:45)
	at org.eclipse.buildship.core.internal.workspace.SynchronizeGradleBuildOperation$1.run(SynchronizeGradleBuildOperation.java:88)
	at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:2295)
	at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:2317)
	at org.eclipse.buildship.core.internal.workspace.SynchronizeGradleBuildOperation.synchronizeProjectsWithWorkspace(SynchronizeGradleBuildOperation.java:85)
	at org.eclipse.buildship.core.internal.workspace.SynchronizeGradleBuildOperation.run(SynchronizeGradleBuildOperation.java:67)
	at org.eclipse.buildship.core.internal.DefaultGradleBuild$SynchronizeOperation.runInToolingApi(DefaultGradleBuild.java:229)
	at org.eclipse.buildship.core.internal.operation.DefaultToolingApiOperationManager$WorkspaceRunnableAdapter.run(DefaultToolingApiOperationManager.java:57)
	at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:2295)
	at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:2322)
	at org.eclipse.buildship.core.internal.operation.DefaultToolingApiOperationManager.run(DefaultToolingApiOperationManager.java:38)
	at org.eclipse.buildship.core.internal.DefaultGradleBuild$SynchronizeOperation.run(DefaultGradleBuild.java:191)
	at org.eclipse.buildship.core.internal.DefaultGradleBuild.synchronize(DefaultGradleBuild.java:99)
	at org.eclipse.buildship.core.internal.workspace.SynchronizationJob.runInToolingApi(SynchronizationJob.java:63)
	at org.eclipse.buildship.core.internal.workspace.SynchronizationJob.runInToolingApi(SynchronizationJob.java:29)
	at org.eclipse.buildship.core.internal.operation.ToolingApiJob$1.runInToolingApi(ToolingApiJob.java:53)
	at org.eclipse.buildship.core.internal.operation.DefaultToolingApiOperationManager$WorkspaceRunnableAdapter.run(DefaultToolingApiOperationManager.java:57)
	at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:2295)
	at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:2322)
	at org.eclipse.buildship.core.internal.operation.DefaultToolingApiOperationManager.run(DefaultToolingApiOperationManager.java:38)
	at org.eclipse.buildship.core.internal.operation.ToolingApiJob.run(ToolingApiJob.java:64)
	at org.eclipse.core.internal.jobs.Worker.run(Worker.java:63)
Caused by: org.gradle.internal.typeconversion.TypeConversionException: Cannot convert string value 'VERSION_13' to an enum value of type 'org.gradle.api.JavaVersion' (valid case insensitive values: VERSION_1_1, VERSION_1_2, VERSION_1_3, VERSION_1_4, VERSION_1_5, VERSION_1_6, VERSION_1_7, VERSION_1_8, VERSION_1_9, VERSION_1_10, VERSION_11, VERSION_12, VERSION_HIGHER)
	at org.gradle.internal.typeconversion.EnumFromCharSequenceNotationParser.convert(EnumFromCharSequenceNotationParser.java:38)
	at org.gradle.internal.typeconversion.EnumFromCharSequenceNotationParser.convert(EnumFromCharSequenceNotationParser.java:25)
	at org.gradle.internal.typeconversion.NotationConverterToNotationParserAdapter.parseNotation(NotationConverterToNotationParserAdapter.java:31)
	at org.gradle.tooling.internal.adapter.ProtocolToModelAdapter.adaptToEnum(ProtocolToModelAdapter.java:177)
	... 50 more
Caused by: java.lang.IllegalArgumentException: Cannot convert string value 'VERSION_13' to an enum value of type 'org.gradle.api.JavaVersion' (valid case insensitive values: VERSION_1_1, VERSION_1_2, VERSION_1_3, VERSION_1_4, VERSION_1_5, VERSION_1_6, VERSION_1_7, VERSION_1_8, VERSION_1_9, VERSION_1_10, VERSION_11, VERSION_12, VERSION_HIGHER)
	at org.gradle.util.GUtil.toEnum(GUtil.java:485)
	at org.gradle.internal.typeconversion.EnumFromCharSequenceNotationParser.convert(EnumFromCharSequenceNotationParser.java:36)
	... 53 more

[donat]

Is this still an issue? IIRC the latest version works with an even newer Java version.

[donat]

This has been fixed in Gradle: gradle/gradle#14444
The latest Buildship version uses a Gradle Tooling API that contains that fix.