javaintellij-ideaannotationsexternal-annotations

Change external annotations location in IDEA 2019.3+

IntelliJ IDEA lets you add external annotations.

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However, the files go straight into the project's root directory.

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How do I change the folder?
I can't find a setting.

Solution

  • This behavior is extremely confusing, and took me a long IDEA debug session to understand.
    Let's say we start with a clean situation, and we add an external Annotation to a method of a library.

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    A popup appears, letting us choose the external Annotations root directory.

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    And we choose untitled3, the project's root directory. But ops, we made a mistake!
    Now how can we change this directory? Where is it stored?
    Well, actually not under any $projectRoot$/.idea/* XML file...

    Let's debug IDEA. The "call" hierarchy is:

    > AnnotateIntentionAction
  > AddAnnotationPsiFix#invoke
    > ExternalAnnotationsManagerImpl#annotateExternally

    The last method annotateExternally calls AnnotationOrderRootType.getFiles(entry), where entry is a LibraryOrderEntry.

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    Here orderEntry.getRootFiles(getInstance()) gets called and the resulting VirtualFile(s) are used as library's external Annotations roots.

    Where are they stored? 

    > Project structure
  > Modules
    > *your main module with dependencies*
      > *your library*
        > DOUBLE LEFT CLICK

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    Now press CANC over the Annotations entry, and you're done... Finally.
    You can restart over.