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JavaFX Preloader configuration IntelliJ IDEA (Java 9 & up)

Is there any equivalent of this JavaFX Preloader and Netbeans, for the IntelliJ editor either online that I'm not finding or in someones noggin?
I've followed these posts
How to create splash screen as a Preloader in JavaFX standalone application?,
Java 9 JavaFX Preloader but I'm still a little lost and unsure - I end up with 3 main functions (1 for Main containing code below, 1 for TestPreLoader extending PreLoader and 1 for MyApplication extending Application) and Application.launch in
public class Main {
public static void main(String[] args) {
System.setProperty("javafx.preloader", "TestPreLoader");
Application.launch("MyApplication", args);
}
}
will not accept args as a parameter even though the types are identical.
Also, I've tried this from jetbrains but it doens't tell me anything about preloaders or how to link it with the application or why it's important. https://www.jetbrains.com/idea/help/applications-with-a-preloader-project-organization-and-packaging.html
Anyone have any ideas? Thanks

So I figured it out, it was a little silly. Turns out I just needed to do this.
public class Main {
public static void main(String[] args) {
System.setProperty("javafx.preloader", TestPreLoader.class.getCanonicalName());
Application.launch(MyApplication.class, args);
}
}

How should I unit test the main method of a JavaFX program?

Right now, I'm considering incorporating 100% code coverage into my project. However, I'm having trouble unit testing the main entry point of my code:
public static void main(String[] args) {
launch(args);
}
This method is difficult to test because it launches an entirely new JavaFX program in the background. In addition to this behavior, a JavaFX program cannot be started more than once. Moreover, the documentation for javafx.application.Application explictly states that, "A JavaFX Application should not attempt to use JavaFX after the FX toolkit has terminated or from a ShutdownHook, that is, after the stop() method returns or System.exit(int) is called."
I am encountering this project because I'm also working with TestFX, a library that helps with clean testing for JavaFX. However, this library does not offer support for the testing of the main method, and as a result I have to write a workaround. There is a possibility of the developers of TestFX knowing about a possible workaround for this problem, for each and every unit tested method, a new instance of an Application is started. Perhaps there could be a way to completely shutdown and reset all variables of a JavaFX program.
To be fair, this method is not that significant to test, however it would be pleasant to have 100% code coverage. It would be entirely reasonable to not test this method as well. The full class can be found below:
package com.meti.app;
import javafx.application.Application;
import javafx.stage.Stage;
/**
* #author SirMathhman
* #version 0.0.0
* #since 4/5/2019
*/ //Main MUST remain public in order for JavaFX Application to start.
public class Main extends Application {
static InfinityImpl implementation = new Infinity();
static Main instance;
#Override
public void start(Stage primaryStage) {
instance = this;
implementation.start(primaryStage);
}
#Override
public void stop() {
implementation.stop();
instance = null;
}
public static void main(String[] args) {
launch(args);
}
}
The static variables above are irrelevant to the aforementioned question and are used for testing purposes in another class which ensures that the delegation works correctly. The application delegates most of the operations to a delegate class which makes the code easier to test.
Moreover, IntelliJ doesn't allow methods to be excluded during code testing.
If you have any other questions, please let me know. Thank you!
Some additional reading:
How to call launch() more than once in java
https://github.com/TestFX/TestFX/blob/master/subprojects/testfx-core/src/main/java/org/testfx/api/FxToolkit.java

Java processing applet not running

When I try to run my java code for processing it shows an error "selection does not contain applet". This is how I am supposed to run my code.
Here is my code:
package proccesing;
import processing.core.*;
public class proccesing extends PApplet {
public void setup() {
background(100,100);
}
public void draw() {
line(0,0,0,100);
}
}

As of Processing 3, PApplet no longer extends Applet. In other words, you can't deploy as an applet anymore.
You could try using the Applet exporting tool, but you're much better off using Processing.js to deploy as JavaScript. Applets are pretty much dead and shouldn't really be used anymore.

how to print "hello world" without MAIN method and also without using STATIC and FINAL key word in java

class a {
public static void main(String args[]) {
}
}
i want to print "hello world" without touch or use above code and also without use of static and final keyword......

What are the different ways to initiate code execution.
Use public static void main(String args[]) { ... }
Use your static class initializer static { ... }. Problem: You need to get the class to load first. Solution: attempt to start the main method, but that means you need to have at least an empty main. However - OP states we cannot use 'static'.
Use an instance initializer { ... }. Problem: How do you instantiate an instance. Solution: initialize a static field with a class instance. However - OP states we cannot use static fields.
So what is left. I assume that we can use the empty main posted by the OP. From there on we build up a 4th solution:
public enum Play {
PLAY;
{ System.out.println("Hello World!"); }
public static void main(String args[]) { }
}
This should fulfill the conditions:
we do not modify the static main method, although we need the empty body just to get the class loaded.
we do not use a static initializer, we use an instance initializer instead.
to instantiate, and get the instance initializer started, we use an enum. Enum's start the initializer for each instance, meaning for each of the enum constants.
Also note the output when you try to execute a class without a main:
$ java -classpath . Play
Error: Main method not found in class Play, please define the main method as:
public static void main(String[] args)
or a JavaFX application class must extend javafx.application.Application
So that leaves us also the clue that we potentially can use javafx.application.Application. I did not investigate this trail any further.

You can create a JavaFX application, which is usually for displaying a GUI, and use it to output hello, world to the console and immediately shut the JavaFX GUI system down. JavaFX applications are executed by a special launch path in the java launcher. JavaFX applications do not need a main, static and final keywords.
The following snippet is just for demo purposes, I wouldn't recommend writing a JavaFX application unless you actually wish to display a GUI.
import javafx.application.Application;
import javafx.application.Platform;
import javafx.stage.Stage;
public class PlayApp extends Application {
#Override
public void start(Stage stage) {
System.out.println("hello, world");
Platform.exit();
}
}
// Totally useless code from the original question
// goes below the real app code and is just ignored
// and never used when the application runs.
class a {
public static void main(String args[]) {
}
}
You need to use Oracle Java 8+ to compile and execute the JavaFX application as below:
javac PlayApp.java
java PlayApp
The a class is in the PlayApp.java file only to meet the original poster's requirement from a comment:
it means the above code is fixed, you can't modify the above code but yes u can write anything to print "hello world" above or belove this code
Really, if you are writing a console application, just use a standard app format (with a static main method) instead:
class HelloWorldApp {
public static void main(String[] args) {
System.out.println("Hello World!"); // Display the string.
}
}
Unrelated advice on asking questions
In future, if you post such questions, I suggest that you also supply the reason for the question and why the bizarre constraints are placed on solutions. Also, address concerns such as WorldEnder's first comment on your question: "is this a code challenge? If not.. why?"

You can't just print "hello world" without MAIN method and also without using STATIC and FINAL key word in java because the main method is a function required you don't have to apply any rocket science in that thing if u are using intelliJ IDEA or any other IDE anyways this is the code
public class Basics_Of_Java {
public static void main(String[] args) {
System.out.println("Hello world");
basics of java in 1st line is the name of the java file you may have another name.

NoClassDefFoundError in Java Applet on invokeLater()

I have an applet I've built using NetBeans, called AKApplet. It runs fine in the IDE, but when I put it in a web page it throws the following error:
Exception in thread "Thread-15" java.lang.NoClassDefFoundError: AKApplet$2
at AKApplet.run(AKApplet.java:675)
The applet uses the run() method to load some data in the background while keeping the UI responsive. Pretty standard stuff. At line 675, after the data has been loaded, I'm trying to update the UI components using invokeLater():
public void run() {
// ... data loads ...
// line 675:
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
userMessages.setText("Data loaded.");
panelList.setVisible(true);
validate();
}
});
}
The components I'm trying to update are userMessages, a JLabel and panelList which is a Panel. I don't think it's getting that far however.
Does anyone know what might be happening? At this point the applet has loaded and the components can be seen and have been updated, etc.

Make sure you're deploying not only AKApplet.class, but also AKApplet$1.class, AKApplet$2.class, etc.

I guess I don't understand what the $ classes refer to. There is only a single AKApplet class, no inner classes. There are no static definitions either.
I do have two other classes defined, but they are separate classes:
class ThreadFlags { /*...*/ }
class DeleteButton extends JLabel { /*...*/ }
Also, I've verified that they are in AKApplet.jar file at the root level:
META-INF/MANIFEST.MF
META-INF/AKAPPLET.SF
META-INF/AKAPPLET.DSA
META-INF/
AKApplet.class
DeleteButton.class
ThreadFlags.class
Update: Ok, I found the AKApplet$.class files in the /build/classes/ directory of the NetBeans project. I added them, and it works. Thanks for your help. Can someone give me a brief explanantion of what those files are? As I said, there are no inner classes that I've defined...

Are there any static definitions in the second inner class of AKApplet that could throw any kind of exception?
Exceptions in the static initializer are the most common cause for NoClassDefFoundErrors after you have made sure that the class file exists and is on the classpath.