Java 26 support in IntelliJ IDEA Early Access Program

Hi Tommer Francis, 

Java 26 is not officially supported in IntelliJ IDEA 2025.3 EAP 4 yet.

To stay informed about upcoming updates and Java 26 support, follow us on X and subscribe to our blog.

Ilnur Galimov When I tried to compile the Java code, I got the following error message:

Internal error (java.lang.IllegalStateException): Storage for [C:\Users\PC\AppData\Local\JetBrains\IntelliJIdea2025.3\compile-server\untitled_4e514ea4\mappings-graph\string-table] is already registered

java.lang.IllegalStateException: Storage for [C:\Users\PC\AppData\Local\JetBrains\IntelliJIdea2025.3\compile-server\untitled_4e514ea4\mappings-graph\string-table] is already registered

at com.intellij.util.io.FilePageCache.registerPagedFileStorage(FilePageCache.java:411)

at com.intellij.util.io.PagedFileStorage.<init>(PagedFileStorage.java:74)

at com.intellij.util.io.ResizeableMappedFile.<init>(ResizeableMappedFile.java:71)

at com.intellij.util.io.PersistentBTreeEnumerator.<init>(PersistentBTreeEnumerator.java:130)

at com.intellij.util.io.PersistentBTreeEnumerator.<init>(PersistentBTreeEnumerator.java:105)

at com.intellij.util.io.PersistentEnumerator.<init>(PersistentEnumerator.java:28)

at com.intellij.util.io.PersistentStringEnumerator.<init>(PersistentStringEnumerator.java:43)

at org.jetbrains.jps.incremental.storage.graph.PersistentMapletFactory.<init>(PersistentMapletFactory.java:46)

at org.jetbrains.jps.incremental.storage.BuildDataManager.createDependencyGraph(BuildDataManager.java:425)

at org.jetbrains.jps.incremental.storage.BuildDataManager.clean(BuildDataManager.java:398)

at org.jetbrains.jps.incremental.IncProjectBuilder.cleanOutputRoots(IncProjectBuilder.java:711)

at org.jetbrains.jps.incremental.IncProjectBuilder.runBuild(IncProjectBuilder.java:541)

at org.jetbrains.jps.incremental.IncProjectBuilder.build(IncProjectBuilder.java:253)

at org.jetbrains.jps.cmdline.BuildRunner.runBuild(BuildRunner.java:158)

at org.jetbrains.jps.cmdline.BuildSession.runBuild(BuildSession.java:395)

at org.jetbrains.jps.cmdline.BuildSession.run(BuildSession.java:211)

at org.jetbrains.jps.cmdline.BuildMain$MyMessageHandler.lambda$channelRead0$0(BuildMain.java:213)

at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1090)

at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:614)

at java.base/java.lang.Thread.run(Thread.java:1474)

Suppressed: java.lang.Exception: Storage[C:\Users\PC\AppData\Local\JetBrains\IntelliJIdea2025.3\compile-server\untitled_4e514ea4\mappings-graph\string-table] registration stack trace

at com.intellij.util.io.FilePageCache.registerPagedFileStorage(FilePageCache.java:438)

at com.intellij.util.io.PagedFileStorage.<init>(PagedFileStorage.java:74)

at com.intellij.util.io.ResizeableMappedFile.<init>(ResizeableMappedFile.java:71)

at com.intellij.util.io.PersistentBTreeEnumerator.<init>(PersistentBTreeEnumerator.java:130)

at com.intellij.util.io.PersistentBTreeEnumerator.<init>(PersistentBTreeEnumerator.java:105)

at com.intellij.util.io.PersistentEnumerator.<init>(PersistentEnumerator.java:28)

at com.intellij.util.io.PersistentStringEnumerator.<init>(PersistentStringEnumerator.java:43)

at org.jetbrains.jps.incremental.storage.graph.PersistentMapletFactory.<init>(PersistentMapletFactory.java:46)

at org.jetbrains.jps.incremental.storage.BuildDataManager.createDependencyGraph(BuildDataManager.java:415)

at org.jetbrains.jps.incremental.storage.BuildDataManager.<init>(BuildDataManager.java:131)

at org.jetbrains.jps.incremental.storage.BuildDataManager.<init>(BuildDataManager.java:82)

at org.jetbrains.jps.cmdline.BuildRunner.load(BuildRunner.java:91)

at org.jetbrains.jps.cmdline.BuildMain.main(BuildMain.java:119)

at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:104)

at java.base/java.lang.reflect.Method.invoke(Method.java:565)

at org.jetbrains.jps.cmdline.Launcher.main(Launcher.java:44)

Is it related to the Java 26 version?

Tommer Francis, this issue is known and is currently being investigated under IDEA-380550.
Please upvote and comment on the issue to help us prioritize the fix.

Ilnur Galimov The issue still exists in the IntelliJ IDEA 2025.3 EAP 6 version.

Tommer Francis, thanks for the update! We appreciate you checking this in IntelliJ IDEA 2025.3 EAP 6. The investigation for this issue is still ongoing. Follow IDEA-380550 for updates.

Ilnur Galimov Can you estimate how long it will take to fix this?

Tommer Francis, thanks for following up! I see an update from the developer that the fix is planned to be included in one of the upcoming IntelliJ IDEA 2025.3 EAP updates. You’ll get a notification in the YouTrack issue IDEA-380550 once the fix is available.

Ilnur Galimov That means the IntelliJ IDEA 2025.3 EAP 7 version will definitely include the fix, doesn't it?

Tommer Francis, the fix is now in the master branch and is already being merged into the 2025.3 branch.

The EAP 7 branch was created yesterday, so we’ll see if it can be included there.

Ilnur Galimov The IntelliJ IDEA 2025.3 EAP 7 version does not include the fix.

Tommer Francis, I have updated information: the fix will be included in the IntelliJ IDEA 2025.3 Beta build expected next week.
The exact release date isn’t confirmed yet. I’ll let you know once the Beta is available. 

Ilnur Galimov Can you give me an immediate fix? I cannot wait until the IntelliJ IDEA 2025.3 Beta build will be released.

Tommer Francis, I see that the developers have already provided you with a fix.
Is there anything else I can help you with? 

Ilnur Galimov Okay, it works now, many thanks for your assistance.

Ilnur Galimov 

While I was updating to the IntelliJ IDEA 2025.3 EAP 8 version, I got the following error:

What should I do at the moment?

Tommer Francis, please click Proceed. Let me know how it goes.

Ilnur Galimov I tried to proceed with the update, and then everything works fine. Many thanks for your assistance.

Tommer Francis, please feel free to reach out to us if you have any questions. We’re always happy to help!

Ilnur Galimov It seems that there are some people who have spammed in this post.

Ilnur Galimov It seems that there are some BOTS who have spammed in this post.

Tommer Francis  Sorry for the nuisance caused by the bots. I've marked the spam.