Error:Internal error: (java.util.concurrent.ExecutionException) java.lang.IllegalArgumentException:

No enum constant org.jetbrains.jps.model.java.LanguageLevel.JDK_11

Error:Internal error: (java.util.concurrent.ExecutionException) java.lang.IllegalArgumentException: No enum constant org.jetbrains.jps.model.java.LanguageLevel.JDK_11
java.util.concurrent.ExecutionException: java.lang.IllegalArgumentException: No enum constant org.jetbrains.jps.model.java.LanguageLevel.JDK_11
	at java.util.concurrent.FutureTask.report(FutureTask.java:122)
	at java.util.concurrent.FutureTask.get(FutureTask.java:192)
	at org.jetbrains.jps.model.serialization.JpsProjectLoader.loadModules(JpsProjectLoader.java:394)
	at org.jetbrains.jps.model.serialization.JpsProjectLoader.loadModules(JpsProjectLoader.java:326)
	at org.jetbrains.jps.model.serialization.JpsProjectLoader.loadFromDirectory(JpsProjectLoader.java:196)
	at org.jetbrains.jps.model.serialization.JpsProjectLoader.loadProject(JpsProjectLoader.java:96)
	at org.jetbrains.jps.model.serialization.impl.JpsSerializationManagerImpl.loadModel(JpsSerializationManagerImpl.java:42)
	at org.jetbrains.jps.cmdline.JpsModelLoaderImpl.loadModel(JpsModelLoaderImpl.java:50)
	at org.jetbrains.jps.cmdline.BuildRunner.load(BuildRunner.java:79)
	at org.jetbrains.jps.cmdline.BuildSession.runBuild(BuildSession.java:280)
	at org.jetbrains.jps.cmdline.BuildSession.run(BuildSession.java:137)
	at org.jetbrains.jps.cmdline.BuildMain$MyMessageHandler.lambda$channelRead0$0(BuildMain.java:235)
	at org.jetbrains.jps.service.impl.SharedThreadPoolImpl.lambda$executeOnPooledThread$0(SharedThreadPoolImpl.java:42)
	·········

解決

打開項目右鍵：

無效的源發行版：9

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解決