Java FX异常（媒体播放器应用程序）

Question

我才刚开始使用Java FX，一辈子也搞不清楚为什么这个异常会不断出现。

我有两节课。一个叫主，另一个叫玩家。下面是他们每个人的样子....

package application;

import javafx.application.Application;

import javafx.stage.Stage;

import javafx.scene.Scene;

import javafx.scene.layout.BorderPane;

import javafx.scene.paint.Color;

    public class Main extends Application {
    @Override
    public void start(Stage primaryStage) {
        Player player = new Player("/Applications/Nacho.mp4");
        Scene scene = new Scene (player, 720, 480, Color.BLACK);
        primaryStage.setScene(scene);
        primaryStage.show();
    }

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

package application;

import javafx.scene.layout.BorderPane;

import javafx.scene.layout.Pane;

import javafx.scene.media.Media;

import javafx.scene.media.MediaPlayer;

import javafx.scene.media.MediaView;

    public class Player extends BorderPane {
    Media media;
    MediaPlayer player;
    MediaView view;
    Pane nPane;

    public Player(String file){
        media = new Media(file);
        player = new MediaPlayer(media);
        view = new MediaView(player);
        nPane = new Pane();
        nPane.getChildren().add(view);
        setCenter(nPane);
        player.play();
    }
}

Exception in Application start method
java.lang.reflect.InvocationTargetException

    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at com.sun.javafx.application.LauncherImpl.launchApplicationWithArgs(LauncherImpl.java:389)
    at com.sun.javafx.application.LauncherImpl.launchApplication(LauncherImpl.java:328)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at sun.launcher.LauncherHelper$FXHelper.main(LauncherHelper.java:767)
Caused by: java.lang.RuntimeException: Exception in Application start method
    at com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:917)
    at com.sun.javafx.application.LauncherImpl.lambda$launchApplication$152(LauncherImpl.java:182)
    at com.sun.javafx.application.LauncherImpl$$Lambda$51/1323468230.run(Unknown Source)
    at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.IllegalArgumentException: uri.getScheme() == null! uri == 'Applications/Nacho.mp4'
    at com.sun.media.jfxmedia.locator.Locator.(Locator.java:211)
    at javafx.scene.media.Media.(Media.java:391)
    at application.Player.(Player.java:16)
    at application.Main.start(Main.java:13)
    at com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$159(LauncherImpl.java:863)
    at com.sun.javafx.application.LauncherImpl$$Lambda$54/1046396900.run(Unknown Source)
    at com.sun.javafx.application.PlatformImpl.lambda$runAndWait$172(PlatformImpl.java:326)
    at com.sun.javafx.application.PlatformImpl$$Lambda$47/186276003.run(Unknown Source)
    at com.sun.javafx.application.PlatformImpl.lambda$null$170(PlatformImpl.java:295)
    at com.sun.javafx.application.PlatformImpl$$Lambda$49/287662571.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at com.sun.javafx.application.PlatformImpl.lambda$runLater$171(PlatformImpl.java:294)
    at com.sun.javafx.application.PlatformImpl$$Lambda$48/237061348.run(Unknown Source)
    at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
Exception running application application.Main

如果有人能告诉我如何解决这个问题，我将不胜感激。否则我真的不能推进这个项目。谢谢！

Answer 1

没关系，我想通了，问题是把参数传递给媒体对象。我已经习惯了C++语法，没有意识到正确的方法是

media = new Media("file:///Applications/Nacho.mp4");