656
votes

In Eclipse, when hovering over a method, variable, etc. a tooltip is displayed with the corresponding JavaDocs. Is there such a feature in IntelliJ?

21
You can put the cursor inside the method/variable and press ctrl+q (on PC) or ctrl+j (on mac).tamasd
Should be nice to have that popup while typing the parameters...Andras Balázs Lajtha
I am still unable to see this after enabling as mentioned below for 2017.1 EAP. I even restarted and nada, I hovered for long.killjoy

21 Answers

927
votes

For IntelliJ 13, there is a checkbox in Editor's page in IDE Settings

enter image description here

EDIT: For IntelliJ 14, the option has been moved to Editor > General page. It's the last option in the "Other" group. (For Mac the option is under the menu "IntelliJ Idea" > "Preferences").

EDIT: For IntelliJ 16, it's the second-to-last option in Editor > General > Other.

EDIT: For IntelliJ Ultimate 2016.1, it's been moved to Editor > General > Code Completion. enter image description here

EDIT: For IntelliJ Ultimate 2017.2, aka IntelliJ IDEA 2017.2.3, there are actually two options:

  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.
  1. In Editor > General > Code Completion (sub-item) > Autopopup documention in 1000 ms, for explicitly invoked completion
  • 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.

EDIT: For IntelliJ Ultimate 2020.3, the first option is now located under Editor > Code Editing > Quick Documentation > Show quick documentation on mouse move

145
votes

Up until IntelliJ version 11, no, not just by hovering over it. If the cursor is inside the method- or attribute name, then CTRL+Q will show the JavaDoc on *nix and Windows. On MacOSX, this is CTRL+J.

Quote: "No, the only way to see the full javadoc is to use Quick Doc (Ctrl-Q)." -- http://devnet.jetbrains.net/thread/121174

EDIT

Since IntelliJ 12.1, this is possible. See @ADNow's answer.

100
votes

It is possible in 12.1.

Find idea.properties in the BIN folder inside of wherever your IDE is installed, e.g. C:\Program Files (x86)\JetBrains\IntelliJ\bin

Add a new line to the end of that file:

auto.show.quick.doc=true

Start IDEA and just hover your mouse over something:

enter image description here

28
votes

After doing CTRL+Q, you can

  1. Pin the tooltip (top right corner)
  2. Check Docked Mode (under gear in top right after pinning)
  3. Size as desired
  4. Click icon for Auto show documentation for selected item

Then when you move your cursor, the documentation will appear in this box. It costs you a little screen real estate, but I find it's worth it.

I'd post a screenshot but SO won't let me post images.

24
votes

In Intellij13, you can use Editor configuration like below: enter image description here

24
votes

For Intellij 15, use the checkbox in File > Settings > Editor > General option Show quick documentation on mouse move.

enter image description here

You can also get there by typing "quick" or something similar in the search box:

enter image description here

14
votes

IntelliJ IDEA 14.0.3 Ultimate:

Press Ctrl+Alt+S, then choose Editor\General choose Show quick domentation on mouse move

enter image description here

Tips: Look at the top right conner (gear icon) at JavaDoc pop-up window, You can choose:
- Show Toolbar
- Pinded Mode
- Docked Mode
- Floatting Mode
- Split Mode

enter image description here

9
votes

Adding on to what ADNow said. On the Macintosh:

  1. Right click on IntelliJ IDEA 12
  2. Click on the Show Package Contents menu option
  3. Open the bin folder
  4. Open idea.properties
  5. Add the line:

    auto.show.quick.doc=true

8
votes

The easiest way, at least for me, was:

  • Ctrl+Shift+A
  • Type: show document
  • Show quick documentation on mouse move (set it to ON)
7
votes

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.
3
votes

In IntelliJ IDEA 14, it has moved to: File -> Settings -> Editor -> General -> "Show quick doc on mouse move"

3
votes

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

2
votes

File-->Settings-->Editor

Check "Show quick doc on mouse"

Now when you put the mouse over a method a tooltip with the documentation will appear. Sometimes the tooltip size is too small and you will have to resize it moving the mouse down to the bottom of the tooltip.

1
votes

IDEA has "find action":

Open "Help" menu, type "doc", move cursor to "Quick Documentation" it will be highlighted.

Also "find action" can be called from hot key (you can find it in settings->hotkeys)

1
votes

On mac in IntelliJ Ultimate (trial) 14 I have mine under Settings > Editor > General > Code completion. The tooltip short is F1 on my laptop.

It's called "Autopopup documentation in (ms):"

enter image description here

1
votes

A note for Android Studio (2.3.3 at least) users, because this page came up for my google search "android studio hover javadoc", and android studio is based on Intellij:

See File->Settings->Editor->General: "show quick documentation on mouse moves", rather than File->Settings->Editor->General->Code Completion "Autopopup documentation in (ms) for explicitly invoked completion" and "Autopopup in (ms)", which has been previously talked about.

1
votes

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.

1
votes

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

enter image description here

enter image description here enter image description here

enter image description here

0
votes

On my IntelliJ U on Mac I need to point with cursor on some method, variable etc. and press [cntrl] or [cmd] key. Then click on the link inside popup window which appeared to see JavaDocs

0
votes

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.

-1
votes

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).