How to start JavaFX 11 application outside IDE?

问题

I downloaded:
- OpenJDK 11.0.2
- JavaFX SDK 11.0.2
Both files are extracted to path C:/Program Files/Java/

OS: Windows 10
IDE: NetBeans 10.0

Paths:

JAVA_HOME = C:/Program Files/Java/jdk-11.0.2  
PATH_TO_FX = C:/Program Files/Java/javafx-sdk-11.0.2/lib

Inside Path system variable add %JAVA_HOME%/bin

In NetBeans I created Java Application project named JFXDev which contains one package com. Inside com package is one main class with following code:

package com;

import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.StackPane;
import javafx.stage.Stage;

public class Main extends Application {

        @Override
        public void start(Stage primaryStage) {
            Button btn = new Button();
            btn.setText("Say 'Hello World'");
            btn.setOnAction(new EventHandler<ActionEvent>() {

                @Override
                public void handle(ActionEvent event) {
                    System.out.println("Hello World!");
                }
            });

            StackPane root = new StackPane();
            root.getChildren().add(btn);

            Scene scene = new Scene(root, 300, 250);

            primaryStage.setTitle("Hello World!");
            primaryStage.setScene(scene);
            primaryStage.show();
        }

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

}

Properties of projects are modified:
1) Libraries -> Modulepath added path C:/Program Files/Java/javafx-sdk-11.0.2/lib
2) Libraries -> Classpath added path C:/Program Files/Java/javafx-sdk-11.0.2/lib/javafx.controls.jar
3) Run -> VM Options: added --add-modules=javafx.controls,javafx.fxml

When I start application with NetBeans it works perfectly but I was unable to start application from dist folder. I tried following commands in cmd:

1. Command: java -jar JFXDev.jar

   • Response: Error: could not find or load main class com.Main

2. Command: java --module-path '%PATH_TO_FX% --add-modules=javafx.comntrols JFXDev

   • Response: Error: Could not find or load main class Files/Java/javafx-sdk-11.0.2/lib

3. Command: java --module-path %PATH_TO_FX% --add-modules=javafx.comntrols Main

   • Response: Error: Could not find or load main class Files/Java/javafx-sdk-11.0.2/lib

4. Command: java --module-path %PATH_TO_FX% --add-modules=javafx.comntrols com.Main

   • Response: Error: Could not find or load main class Files/Java/javafx-sdk-11.0.2/lib
5. Command: java --module-path "C:/Program Files/Java/javafx-sdk-11.0.2/lib/" --add-modules=javafx.comntrols com.Main
   • Response: Error: Could not find or load main class Main

Later I added module-info.java file:

module JFXDev {  
    requires javafx.controls;  
    exports com;  
}  

But it doesn't make any difference.
What I'm doing wrong, any advice or suggestion?

I tried steps from https://openjfx.io/openjfx-docs/#install-javafx but I get same error :/

回答1:

"Actual" Answer

Some of those errors you've provided indicate a problem with spaces in your arguments (e.g. C:/Program Files/...). Surround %PATH_TO_FX% with quotes: "%PATH_TO_FX%". Then, as you said in a comment, the correct command line for you is:

java -p "%PATH_TO_FX%" --add-modules javafx.controls -jar <path-to-jar-file> 

---

Rest of Answer

From the information you've provided, it's difficult (for me at least) to tell what exactly the problem is. Instead, I'll give some examples of launching a JavaFX application from the command line, both modular and non-modular.

Let's say you have a project with one class—the main class—named com.example.Main. This class extends Application and displays a simple window. Let's also say that, when the code is modular, the module looks like:

module app {
    requires javafx.controls;
    exports com.example to javafx.graphics;
}

And your project structure looks like this:

\---<project-directory>
    +---out
    |   +---artifacts
    |   |       app-1.0.jar (modular or non-modular)
    |   |
    |   \---classes
    |       |   module-info.class (when modular)
    |       |
    |       \---com
    |           \---example
    |                   Main.class
    |
    \---src
        |   module-info.java (when modular)
        |
        \---com
            \---example
                    Main.java

Then your command line will look like one of the following (Windows oriented):

Non-modular

Exploded Directory

java -p "%PATH_TO_FX%" --add-modules javafx.controls -cp out\classes com.example.Main

Jar File

java -p "%PATH_TO_FX%" --add-modules javafx.controls -jar out\artifacts\app-1.0.jar

Note: Requires Main-Class attribute in the manifest.

Modular

Exploded Directory

java -p "%PATH_TO_FX%;out\classes" -m app/com.example.Main

Jar File

java -p "%PATH_TO_FX%;out\artifacts" -m app/com.example.Main

Or if the Jar was created/updated with --main-class

java -p "%PATH_TO_FX%;out\artifacts" -m app

---

Notes:

• The above assumes that <project-directory> is the working directory.
• -p is shorthand for --module-path
• -m is shorthand for --module
• -cp is shorthand for --class-path or -classpath

来源：https://stackoverflow.com/questions/55652036/how-to-start-javafx-11-application-outside-ide