How to attach JavaDoc .jar for library .jar and get editor to show the documentation?

From @mattflix on February 23, 2019 19:58

I have tried various techniques to specify the JavaDoc .jar that should be attached to a given library .jar (that appears in the "Referenced Libraries" section of the "JAVA DEPENDENCIES" view, and is successfully used by my app), but nothing has worked.

Currently, the only JavaDoc documentation that appears in the editor for me is that for the built-in objects/members, like Object and toString(). No third-party libraries seem to have any JavaDoc exposed in the editor.

Is there any example of a simple project configured with a dependency on a library .jar (that has an associated JavaDoc .jar, also located on the local file system) where the editor is able to display the documentation comments for selected Java types and members?

Copied from original issue: Microsoft/vscode-java-pack#105

Es wird keine Datei, kein Test und kein Einstiegspunkt genannt. Reproduziere das einfache Projekt mit einer lokalen Bibliotheks-.jar und der zugehörigen JavaDoc-.jar und überprüfe anschließend, ob im Editor Dokumentation für Java-Typen und -Member von Drittanbietern angezeigt wird; als erledigt gilt eine dokumentierte funktionierende Konfiguration oder ein bestätigter Fehler.