Intellij and javafx problems [duplicate] - intellij-idea

Question

The problem is when i try to run my main class i get the error from above.
I'm using Intellij IDEA
Added dependencies and plugin in pom.xml
Ran mvn clean install, also mvn clean javafx:run
But I can't run my main class
Here is what i added to pom
<dependency>
<groupId>org.openjfx</groupId>
<artifactId>javafx-controls</artifactId>
<version>19</version>
</dependency>
<dependency>
<groupId>org.openjfx</groupId>
<artifactId>javafx-fxml</artifactId>
<version>19</version>
</dependency>
<plugin>
<groupId>org.openjfx</groupId>
<artifactId>javafx-maven-plugin</artifactId>
<version>0.0.8</version>
<configuration>
<mainClass>App</mainClass>
</configuration>
</plugin>

Answer 1

File > New Project > Generators > JavaFX
I suggest starting with a new project created by IntelliJ IDEA explicitly aimed at JavaFX.
Use the JavaFX option in the Generators list, in the New Project wizard.
You will get a full working example app, that runs successfully.
The code is modularized with a module-info.java file.
The example app uses FXML. If you wish, you can easily delete that. You can use only Java coding without any FXML markup coding — your choice. If you opt out of FXML, delete the dependency for javafx-fxml from your POM.
The POM looks like the following. Notice the inclusion of OpenJFX dependencies.
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns = "http://maven.apache.org/POM/4.0.0"
xmlns:xsi = "http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation = "http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>work.basil.example</groupId>
<artifactId>fxdemo</artifactId>
<version>1.0-SNAPSHOT</version>
<name>fxdemo</name>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<junit.version>5.9.1</junit.version>
</properties>
<dependencies>
<dependency>
<groupId>org.openjfx</groupId>
<artifactId>javafx-controls</artifactId>
<version>19</version>
</dependency>
<dependency>
<groupId>org.openjfx</groupId>
<artifactId>javafx-fxml</artifactId>
<version>19</version>
</dependency>
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter-api</artifactId>
<version>${junit.version}</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter-engine</artifactId>
<version>${junit.version}</version>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.10.1</version>
<configuration>
<source>19</source>
<target>19</target>
</configuration>
</plugin>
<plugin>
<groupId>org.openjfx</groupId>
<artifactId>javafx-maven-plugin</artifactId>
<version>0.0.8</version>
<executions>
<execution>
<!-- Default configuration for running with: mvn clean javafx:run -->
<id>default-cli</id>
<configuration>
<mainClass>work.basil.example.fxdemo/work.basil.example.fxdemo.HelloApplication</mainClass>
<launcher>app</launcher>
<jlinkZipName>app</jlinkZipName>
<jlinkImageName>app</jlinkImageName>
<noManPages>true</noManPages>
<stripDebug>true</stripDebug>
<noHeaderFiles>true</noHeaderFiles>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
By the way, you can replace the property <junit.version>5.9.1</junit.version> and the pair of JUnit dependencies with this simpler single “Aggregator” dependency:
<!-- https://mvnrepository.com/artifact/org.junit.jupiter/junit-jupiter -->
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter</artifactId>
<version>5.9.1</version>
<scope>test</scope>
</dependency>
Like this:
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns = "http://maven.apache.org/POM/4.0.0"
xmlns:xsi = "http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation = "http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>work.basil.example</groupId>
<artifactId>demoFX</artifactId>
<version>1.0-SNAPSHOT</version>
<name>demoFX</name>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<dependencies>
<dependency>
<groupId>org.openjfx</groupId>
<artifactId>javafx-controls</artifactId>
<version>19</version>
</dependency>
<dependency>
<groupId>org.openjfx</groupId>
<artifactId>javafx-fxml</artifactId>
<version>19</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.junit.jupiter/junit-jupiter -->
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter</artifactId>
<version>5.9.1</version>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.10.1</version>
<configuration>
<source>19</source>
<target>19</target>
</configuration>
</plugin>
<plugin>
<groupId>org.openjfx</groupId>
<artifactId>javafx-maven-plugin</artifactId>
<version>0.0.8</version>
<executions>
<execution>
<!-- Default configuration for running with: mvn clean javafx:run -->
<id>default-cli</id>
<configuration>
<mainClass>work.basil.example.demofx/work.basil.example.demofx.HelloApplication</mainClass>
<launcher>app</launcher>
<jlinkZipName>app</jlinkZipName>
<jlinkImageName>app</jlinkImageName>
<noManPages>true</noManPages>
<stripDebug>true</stripDebug>
<noHeaderFiles>true</noHeaderFiles>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>