How do I run a JavaFX app from a SpringBoot app?

Question

I have a Spring Boot App with the following classes in the src/main/java/in/javacoder/overlayapp package

build.gradle

plugins {
    id 'java'
    id 'org.springframework.boot' version '3.0.2'
    id 'io.spring.dependency-management' version '1.1.0'
    id 'application'
    id 'org.openjfx.javafxplugin' version '0.0.13'
}

javafx {
    version = "17"
    modules = [ 'javafx.controls' ]
}

group = 'in.techpro424'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = '17'

configurations {
    compileOnly {
        extendsFrom annotationProcessor
    }
}

repositories {
    mavenCentral()
}

dependencies {
    implementation 'org.springframework.boot:spring-boot-starter-web'
    developmentOnly 'org.springframework.boot:spring-boot-devtools'
    annotationProcessor 'org.springframework.boot:spring-boot-configuration-processor'
    testImplementation 'org.springframework.boot:spring-boot-starter-test'
}

tasks.named('test') {
    useJUnitPlatform()
}

CoordinateOverlayAppApplication.java

package in.techpro424.coordinateoverlayapp;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class CoordinateOverlayAppApplication {

    public static void main(String[] args) {
        SpringApplication.run(CoordinateOverlayAppApplication.class, args);
    }

}

CoordinateRestController.java

package in.techpro424.coordinateoverlayapp;

import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class CoordinateRestController {
    public static double xCoord;
    public static double yCoord;
    public static double zCoord;
  
    @PostMapping(value = "/coordinateOverlay")
    public int receiveCoordinates(@RequestParam(name = "xCoordinate") Double xCoordinate, @RequestParam(name = "yCoordinate") Double yCoordinate, @RequestParam(name = "zCoordinate") Double zCoordinate) {
      CoordinateRestController.xCoord = xCoordinate;
      System.out.println(CoordinateRestController.xCoord);

      CoordinateRestController.yCoord = yCoordinate;
      System.out.println(CoordinateRestController.yCoord);

      CoordinateRestController.zCoord = zCoordinate;
      System.out.println(CoordinateRestController.zCoord);

      javafx.application.Application.launch(RenderCoordinateOverlay.class);

      return 1;
    }


}

RenderCoordinateOverlay.java

package in.techpro424.coordinateoverlayapp;

import javafx.application.Application;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.paint.Color;
import javafx.scene.text.Text;
import javafx.stage.Stage;
import javafx.stage.StageStyle;

public class RenderCoordinateOverlay extends Application {
    double radius = 50;

    @Override
    public void start(Stage primaryStage) {

        Group root = new Group();

        Text coordinates = new Text();
        coordinates.setText("X:" + CoordinateRestController.xCoord + ", Y:" + CoordinateRestController.yCoord + ", Z:" + CoordinateRestController.zCoord);

        root.getChildren().add(coordinates);

        Scene scene = new Scene(root, Color.TRANSPARENT);

        scene.getRoot().setStyle("-fx-background-color: transparent");

        primaryStage.initStyle(StageStyle.TRANSPARENT);
        primaryStage.setScene(scene);
        primaryStage.show();
        primaryStage.setAlwaysOnTop(true);

        
    }
    public static void main(String[] args) {
        launch(args);
    }
}

I want to render this overlay on the screen whenever I receive the POST request with the specified params

I tried using javafx.application.Application.launch(RenderCoordinateOverlay.class); in the receiveCoordinates() function I expected the overlay to render the text the moment I sent the POST request However, when I sent the POST request, only a completely transparent window was rendered with this error in the console:

2023-01-27T15:01:27.384+05:30  WARN 13060 --- [JavaFX-Launcher] javafx: Unsupported JavaFX configuration: classes were loaded from 'unnamed module @1ec4c0e8'

The SpringBoot application is running on my PC with a display and I expect the UI to be displayed on the PC. I use Postman to send the post.