[java] cannot resolve symbol javafx.application in IntelliJ Idea IDE

I tried to create a JavaFX application in IntelliJ Idea IDE but I got compile error that said:

java: package javafx.application does not exist.

I have changed the Project SDK and the Project Language Level to Java 8, reloaded the project but it didn't help. Then I checked if JavaFX plugin was enabled in the settings.

The search on Google and StackOverflow didn't give me more ideas of what is wrong. Thank for any help in advance.

P.S. I am using IntelliJ Idea 14.0 with java8.1.0_25 on archlinux OS.

This should be your perfect solution. Try and enjoy. If some command does not work properly that means if you get any error, try to solve it yourself. I have given you the main thing you need. If your application is in a different location, or your system architecture is different, solve it yourself. It's very easy to do it. Just follow my given solution.

Step 0:

sudo apt-get install openjdk-8-jre

Step: 1

sudo apt-get install openjfx

Step 2:

sudo cp /usr/share/java/openjfx/jre/lib/ext/* /usr/lib/jvm/java-1.8.0-openjdk-amd64/lib

Step 3:

sudo cp /usr/share/java/openjfx/lib/* /usr/lib/jvm/java-1.8.0-openjdk-amd64/lib

Step 4:

sudo chmod 777 -R /usr/lib/jvm/java-1.8.0-openjdk-amd64

now open a new project or rebuild your project. Good luck.

You can use the one that comes with IntelliJ: <intellij>/jre64/lib/ext/jfxrt.jar.

In IntelliJ Idea,

Check the following things are configured properly,

Step 1:

File -> Setting -> Plugins -> search javafx and make sure its enabled.

Step 2: Project Structure (Ctrl+Shift+Alt+s)

Platform Settings -> SDKs -> 1.8 -> Make sure Classpath should have "jre\lib\ext\jfxrt.jar"

Step 3:

Project Settings -> Project -> Project SDK - should be selected 1.8

Project Settings -> Project -> Project language level - configured as 8

Ubuntu: If not found jfxrt.jar in your SDKs then install sudo apt-get install openjfx

You need to download the java-openjfx package from the official Arch Linux repos. (Also, make sure you have the openjdk8-openjdk package). After doing that, open your project in Intellij and go to Project-Structure -> SDKs -> 1.8 -> Classpath and try removing the old JDK you had and clicking on the directory for the new JDK that will now contain jfxrt.jar.

You might have a lower project language level than your JDK.

Check if: "Projeckt structure/project/Project-> language level" is lower than your JDK. I had the same problem with JDK 9 and the language level was per default set to 6.

I set the Project Language Level to 9 and everything worked fine after that.

You might have the same issue.

I had the same problem, in my case i resolved it by:

1) going to File-->Project Structure---->Global libraries 2) looking for jfxrt.jar included as default in the jdk1.8.0_241\lib (after installing it) 3)click on + on top left to add new global library and i specified the path of my jdk1.8.0_241 Ex :(C:\Program Files\Java\jdk1.8.0_241).

I hope this will help you

Another way to resolve the problem : Click the left mouse's button on the project folder in the project structure at the left, and click on "open module settings" in the list of actions In the new windows, click on SDKs which is under the menu title "Platform settngs" Then check on the "Classpath" list if you can find the jfxrt plugin path, if not, click on the + symbol on the right and select the repertory of the jfxrt plugin (C:\Program Files\Java\jdk1.8.0\jre\lib\ext\jfxrt.jar on my desktop)

Sample Java application:

I'm crossposting my answer from another question here since it is related and also seems to solve the problem in the question.

Here is my example project with OpenJDK 12, JavaFX 12 and Gradle 5.4

• Opens a JavaFX window with the title "Hello World!"
• Able to build a working runnable distribution zip file (Windows to be tested)
• Able to open and run in IntelliJ without additional configuration
• Able to run from the command line

I hope somebody finds the Github project useful.

Instructions for the Scala case:

Additionally below are instructions that work with the Gradle Scala plugin, but don't seem work with Java. I'm leaving this here in case somebody else is also using Scala, Gradle and JavaFX.

1) As mentioned in the question, the JavaFX Gradle plugin needs to be set up. Open JavaFX has detailed documentation on this

2) Additionally you need the the JavaFX SDK for your platform unzipped somewhere. NOTE: Be sure to scroll down to Latest releases section where JavaFX 12 is (LTS 11 is first for some reason.)

3) Then, in IntelliJ you go to the File -> Project Structure -> Libraries, hit the ?-button and add the lib folder from the unzipped JavaFX SDK.

For longer instructions with screenshots, check out the excellent Open JavaFX docs for IntelliJ I can't get a deep link working, so select JavaFX and IntelliJ and then Modular from IDE from the docs nav. Then scroll down to step 3. Create a library. Consider checking the other steps too if you are having trouble.

It is difficult to say if this is exactly the same situation as in the original question, but it looked similar enough that I landed here, so I'm adding my experience here to help others.