IntelliJ show JavaDocs tooltip on mouse over

From IntelliJ Ultimate 2018.1.5, aka IntelliJ IDEA 2018.1.5, till 2019.3 , there are actually two options under File -> Preferences:

1. In Editor > General > Other (section) > Show quick documentation on mouse move - delay 500 ms
   • Select this check box to show quick documentation for the symbol at caret. The quick documentation pop-up window appears after the specified delay.
2. In Editor > General > Code Completion (sub-item) > Auto-display documentation in 1000 ms
   • Select this check box to have IntelliJ IDEA automatically show a pop-up window with the documentation for the class, method, or field currently highlighted in the lookup list. If this check box is not selected, use Ctrl+Q to show quick documentation for the element at caret.
   • Quick documentation window will automatically pop up with the specified delay in those cases only, when code completion has been invoked explicitly. For the automatic code completion list, documentation window will only show up on pressing Ctrl+Q.

In Intellij 2019, I did: File > Settings > Editor > General option Show quick documentation on mouse move.

I tried many ways mentioned here, especially the preference - editor - general - code completion - show documentation popup in.. isn't working in version 2019.2.2

Finally, i am just using F1 while caret is on the type/method and it displays the documentation nicely. This is not ideal but helpful.

In 2020.1 there is in editor javadocs rendering has been added. Screen shots borrowed from intellij documentation.

All of the above methods are useful but one basic thing missing you need to have src.zip in your JDK (C:\Program Files\Java\jdk1.8.0_171). I assumed it comes preinstalled but for some reason, it was not present in my installation. Another thing to check is if your project is using the specified (1.8.0_171 in this case) JDK.

The answer is CTRL + P (NOT CTRL + Q)

Someone else posted this answer on JetBrains forum: The idea is a different IDE. Try to discover its features and try to make the best of it, rather than trying to emulate whatever you used before. For the most part, Idea has very high usability (much better than Eclipse IMHO) and is streamlined for supporting code editing as best as possible (rather than relying on wizards too much for example).

• Javadoc: Ctrl-Q
• A quick view of the implementation: Ctrl-Shift-I
• Show context: Alt-Q
• Show parameters (in a method call): Ctrl-P
• Show error description. Ctrl-F1

... plus many more shortcuts to navigate in code and different idea views.

I think it rather nice that you can see just the specific bit of information you are interested in with a simple keystroke. Have a look at the menus which will also show the possibly modified shortcuts for your keymap.

0 Avatar Jens Voß Created June 12, 2008, 09:26 And, elsandros, in addition to what Stephen writes: Since you seem to be interested in IDEA's keyboard shortcuts, I highly recommend the "Key Promoter" plugin which helps you memorize the relevant shortcuts quickly.

Also very useful is the "Goto Action" feature, invoked by Ctrl-Shift-A. In the popup, you can enter a keyword (e.g. "Javadoc"), and the IDE tells you the available actions matching your search, along with keyboard shortcuts and the containing action groups (which often also give you a clue about how to navigate to the action using the menu).