IntelliJ idea how to set up a Java Help document

Open idea the jar packages I refer to are placed in
Project Structure-->modules-->libs folder (double-click)
Double-click the folder where the jar package is located and jump out of the dialog box.
1. If the API corresponding Javadoc document is local, click the button indicated by the Red arrow and select the Javadoc folder
2. If the API is online, copy the URL and click on the button indicated by the blue arrow to write the corresponding API URL in the popup input box.
When you are finished writing Java code, there is a question, ctrl+q will pop up the introduction of the API.
The latest experiment can be directly added to idea and used in the "zip" format of the network as follows:
Project structure-->modules-->dependencies--> Click on the "+" sign-->jars Or directores Select the corresponding zip format of the Help file directory is OK, Use Ctrl+q to bring up the API documentation when you use it.
But this is set to follow the project, I asked not to follow the project, only set once, so the final method is:
Open idea File--project stucture--sdks--doucumentation paths--+ Add path: (Can not choose the zip format of the file, to select the extracted files add, use the same method as above)

Finally, the ultimate trick. Implements a method for hovering over a Java Help document:

In the latest version of idea: Settings-->editor-->general-->quick doc (tick show quick doc on mouse move Delay (ms): 500)

IntelliJ idea how to set up a Java Help document