java - 运行 JavaFx 媒体应用程序时出现模块错误

Question

当我运行我的 JavaFX 11 应用程序使用以下命令:

/usr/lib/jvm/java-11-openjdk-amd64/bin/java 
-p ~/.m2/repository/org/openjfx/javafx-swing/11/javafx-swing-11.jar:
~/.m2/repository/org/openjfx/javafx-swing/11/javafx-swing-11-linux.jar:
~/.m2/repository/org/openjfx/javafx-graphics/11/javafx-graphics-11.jar:
~/.m2/repository/org/openjfx/javafx-graphics/11/javafx-graphics-11-linux.jar:
~/.m2/repository/org/openjfx/javafx-base/11/javafx-base-11.jar:
~/.m2/repository/org/openjfx/javafx-base/11/javafx-base-11-linux.jar:
~/.m2/repository/org/openjfx/javafx-controls/11/javafx-controls-11.jar:
~/.m2/repository/org/openjfx/javafx-controls/11/javafx-controls-11-linux.jar:
~/.m2/repository/org/openjfx/javafx-media/11/javafx-media-11.jar:
~/.m2/repository/org/openjfx/javafx-media/11/javafx-media-11-linux.jar 
--add-modules javafx.controls,javafx.graphics
-classpath ~/development/intellij/OpenPatrician/OpenPatricianStandalone/target/classes:
~/.OpenPatrician/plugins/maps/MinimalMap-Plugin.jar:
~/development/intellij/OpenPatrician/OpenPatricianDisplay/target/classes:
~/.m2/repository/ch/sahits/sahitsUtil/1.2.4/sahitsUtil-1.2.4.jar:
~/.m2/repository/junit/junit/4.12/junit-4.12.jar:
~/.m2/repository/org/hamcrest/hamcrest-core/1.3/hamcrest-core-1.3.jar:
~/.m2/repository/org/springframework/boot/spring-boot-starter-log4j2/2.1.0.RELEASE/spring-boot-starter-log4j2-2.1.0.RELEASE.jar:
~/.m2/repository/org/apache/logging/log4j/log4j-slf4j-impl/2.11.1/log4j-slf4j-impl-2.11.1.jar:
~/.m2/repository/org/slf4j/slf4j-api/1.7.25/slf4j-api-1.7.25.jar:
~/.m2/repository/org/apache/logging/log4j/log4j-api/2.11.1/log4j-api-2.11.1.jar:
~/.m2/repository/org/apache/logging/log4j/log4j-core/2.11.1/log4j-core-2.11.1.jar:
~/.m2/repository/org/apache/logging/log4j/log4j-jul/2.11.1/log4j-jul-2.11.1.jar:
~/.m2/repository/org/slf4j/jul-to-slf4j/1.7.25/jul-to-slf4j-1.7.25.jar:
~/.m2/repository/commons-cli/commons-cli/1.4/commons-cli-1.4.jar:
~/development/intellij/OpenPatrician/OpenPatricianImage/target/classes:
~/development/intellij/OpenPatrician/OpenPatricianModel/target/classes:
~/development/intellij/OpenPatrician/GameEvent/target/classes:
~/.m2/repository/org/glassfish/jaxb/jaxb-runtime/2.3.1/jaxb-runtime-2.3.1.jar:
~/.m2/repository/org/glassfish/jaxb/txw2/2.3.1/txw2-2.3.1.jar:
~/.m2/repository/com/sun/istack/istack-commons-runtime/3.0.7/istack-commons-runtime-3.0.7.jar:
~/.m2/repository/org/jvnet/staxex/stax-ex/1.8/stax-ex-1.8.jar:
~/.m2/repository/com/sun/xml/fastinfoset/FastInfoset/1.2.15/FastInfoset-1.2.15.jar:
~/.m2/repository/javax/activation/javax.activation-api/1.2.0/javax.activation-api-1.2.0.jar:
~/.m2/repository/org/openjfx/javafx-swing/11/javafx-swing-11.jar:
~/.m2/repository/org/openjfx/javafx-swing/11/javafx-swing-11-linux.jar:
~/.m2/repository/org/openjfx/javafx-graphics/11/javafx-graphics-11.jar:
~/.m2/repository/org/openjfx/javafx-graphics/11/javafx-graphics-11-linux.jar:
~/.m2/repository/org/openjfx/javafx-base/11/javafx-base-11.jar:
~/.m2/repository/org/openjfx/javafx-base/11/javafx-base-11-linux.jar:
~/development/intellij/OpenPatrician/OpenPatricianSound/target/classes:
~/development/intellij/OpenPatrician/OpenPatricianUtilities/target/classes:
~/.m2/repository/org/springframework/spring-beans/5.1.2.RELEASE/spring-beans-5.1.2.RELEASE.jar:
~/.m2/repository/org/openjfx/javafx-controls/11/javafx-controls-11.jar:
~/.m2/repository/org/openjfx/javafx-controls/11/javafx-controls-11-linux.jar:
~/.m2/repository/commons-io/commons-io/2.6/commons-io-2.6.jar:
~/.m2/repository/com/thoughtworks/xstream/xstream/1.4.10/xstream-1.4.10.jar:
~/.m2/repository/xmlpull/xmlpull/1.1.3.1/xmlpull-1.1.3.1.jar:
~/.m2/repository/xpp3/xpp3_min/1.1.4c/xpp3_min-1.1.4c.jar:
~/.m2/repository/javax/xml/bind/jaxb-api/2.3.1/jaxb-api-2.3.1.jar:
~/.m2/repository/javax/annotation/javax.annotation-api/1.3.2/javax.annotation-api-1.3.2.jar:
~/.m2/repository/org/openjfx/javafx-media/11/javafx-media-11.jar:
~/.m2/repository/org/openjfx/javafx-media/11/javafx-media-11-linux.jar:
~/.m2/repository/org/springframework/spring-context/5.1.2.RELEASE/spring-context-5.1.2.RELEASE.jar:
~/.m2/repository/org/springframework/spring-aop/5.1.2.RELEASE/spring-aop-5.1.2.RELEASE.jar:
~/.m2/repository/org/springframework/spring-expression/5.1.2.RELEASE/spring-expression-5.1.2.RELEASE.jar:
~/.m2/repository/org/springframework/spring-oxm/5.1.2.RELEASE/spring-oxm-5.1.2.RELEASE.jar:
~/.m2/repository/com/google/guava/guava/24.1-jre/guava-24.1-jre.jar:
~/.m2/repository/com/google/code/findbugs/jsr305/1.3.9/jsr305-1.3.9.jar:
~/.m2/repository/org/checkerframework/checker-compat-qual/2.0.0/checker-compat-qual-2.0.0.jar:
~/.m2/repository/com/google/errorprone/error_prone_annotations/2.1.3/error_prone_annotations-2.1.3.jar:
~/.m2/repository/com/google/j2objc/j2objc-annotations/1.1/j2objc-annotations-1.1.jar:
~/.m2/repository/org/codehaus/mojo/animal-sniffer-annotations/1.14/animal-sniffer-annotations-1.14.jar:
~/development/intellij/OpenPatrician/OpenPatricianJavaFX/target/classes:
~/development/intellij/OpenPatrician/OpenPatricianGameEvent/target/classes:
~/development/intellij/OpenPatrician/OpenPatricianClientServerInterface/target/classes:
~/.m2/repository/org/springframework/boot/spring-boot-starter-aop/2.1.0.RELEASE/spring-boot-starter-aop-2.1.0.RELEASE.jar:
~/.m2/repository/org/springframework/boot/spring-boot-starter/2.1.0.RELEASE/spring-boot-starter-2.1.0.RELEASE.jar:
~/.m2/repository/org/yaml/snakeyaml/1.23/snakeyaml-1.23.jar:
~/.m2/repository/org/aspectj/aspectjweaver/1.9.2/aspectjweaver-1.9.2.jar:
~/development/intellij/OpenPatrician/OpenPatricianServer/target/classes:
~/development/intellij/OpenPatrician/OpenPatricianEngine/target/classes:
~/.m2/repository/com/carrotsearch/hppc/0.7.2/hppc-0.7.2.jar:
~/.m2/repository/org/springframework/spring-core/5.1.2.RELEASE/spring-core-5.1.2.RELEASE.jar:
~/.m2/repository/org/springframework/spring-jcl/5.1.2.RELEASE/spring-jcl-5.1.2.RELEASE.jar:
~/.m2/repository/org/reflections/reflections/0.9.11/reflections-0.9.11.jar:
~/.m2/repository/org/javassist/javassist/3.21.0-GA/javassist-3.21.0-GA.jar:
~/development/intellij/OpenPatrician/OpenPatricianData/target/classes:
~/.m2/repository/org/projectlombok/lombok/1.18.2/lombok-1.18.2.jar:
~/.m2/repository/org/springframework/boot/spring-boot-devtools/2.1.0.RELEASE/spring-boot-devtools-2.1.0.RELEASE.jar:
~/.m2/repository/org/springframework/boot/spring-boot/2.1.0.RELEASE/spring-boot-2.1.0.RELEASE.jar:
~/.m2/repository/org/springframework/boot/spring-boot-autoconfigure/2.1.0.RELEASE/spring-boot-autoconfigure-2.1.0.RELEASE.jar 
ch.sahits.game.openpatrician.standalone.OpenPatricianApplication

我遇到了这个错误:

Exception in thread "JavaFX Application Thread" java.lang.IllegalAccessError: class com.sun.media.jfxmediaimpl.NativeMediaManager (in unnamed module @0x4d7be377) cannot access class com.sun.glass.utils.NativeLibLoader (in module javafx.graphics) because module javafx.graphics does not export com.sun.glass.utils to unnamed module @0x4d7be377
    at com.sun.media.jfxmediaimpl.NativeMediaManager.lambda$new$0(NativeMediaManager.java:136)
    at java.base/java.security.AccessController.doPrivileged(Native Method)
    at com.sun.media.jfxmediaimpl.NativeMediaManager.<init>(NativeMediaManager.java:107)
    at com.sun.media.jfxmediaimpl.NativeMediaManager$NativeMediaManagerInitializer.<clinit>(NativeMediaManager.java:78)
    at com.sun.media.jfxmediaimpl.NativeMediaManager.getDefaultInstance(NativeMediaManager.java:90)
    at com.sun.media.jfxmedia.MediaManager.canPlayProtocol(MediaManager.java:78)
    at com.sun.media.jfxmedia.locator.Locator.<init>(Locator.java:239)
    at com.sun.media.jfxmediaimpl.NativeMediaAudioClip.<init>(NativeMediaAudioClip.java:53)
    at com.sun.media.jfxmediaimpl.NativeMediaAudioClip.load(NativeMediaAudioClip.java:63)
    at com.sun.media.jfxmediaimpl.AudioClipProvider.load(AudioClipProvider.java:66)
    at com.sun.media.jfxmedia.AudioClip.load(AudioClip.java:135)
    at javafx.scene.media.AudioClip.<init>(AudioClip.java:83)
    at ch.sahits.game.openpatrician.sound.impl.LoopTrack.lambda$new$0(LoopTrack.java:26)
    at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runLater$10(PlatformImpl.java:428)
    at java.base/java.security.AccessController.doPrivileged(Native Method)
    at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runLater$11(PlatformImpl.java:427)
    at javafx.graphics/com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:96)
    at javafx.graphics/com.sun.glass.ui.gtk.GtkApplication._runLoop(Native Method)
    at javafx.graphics/com.sun.glass.ui.gtk.GtkApplication.lambda$runLoop$11(GtkApplication.java:277)
    at java.base/java.lang.Thread.run(Thread.java:834)

据我了解，我的模块设置有问题，但我不清楚我需要更改什么:

将其他模块添加到 --add-modules哪个？

添加 --add-opens到命令 which modules

完全不同的东西？

Answer 1

TL;博士:您需要确保javafx.media被解析为模块路径中的模块。您可以通过以下任一方式执行此操作:

将其包含在 VM 参数中:--add-modules javafx.controls,javafx.media

或者使您自己的代码模块化，添加适当的 requires javafx.media;指令到您的模块描述符，并使用 --module启动您的应用程序。

如果您不确定如何或在何处设置 IDE 和/或构建工具中的 VM 参数，请查看 Getting Started with JavaFX .

问题
该错误与 Java 9 中添加的 Java 平台模块系统有关。如果您不知道模块是什么以及它们如何工作，请查看此博客: Understanding Java 9 Modules .这是一个小摘录:

Modularity adds a higher level of aggregation above packages. The key new language element is the module—a uniquely named, reusable group of related packages, as well as resources (such as images and XML files) and a module descriptor specifying

• the module’s name
• the module’s dependencies (that is, other modules this module depends on)
• the packages it explicitly makes available to other modules (all other packages in the module are implicitly unavailable to other modules)
• the services it offers
• the services it consumes
• to what other modules it allows reflection

随着模块的引入，JavaFX 也被模块化了。它现在由七个模块组成，可以通过 its Javadoc 看到。 .这些模块在它们之间共享它们的一些内部结构，但不与应用程序开发人员共享。这是通过合格的导出/打开指令完成的。
你的错误
这是你的错误:

java.lang.IllegalAccessError: class com.sun.media.jfxmediaimpl.NativeMediaManager (in unnamed module @0x4d7be377) cannot access class com.sun.glass.utils.NativeLibLoader (in module javafx.graphics) because module javafx.graphics does not export com.sun.glass.utils to unnamed module @0x4d7be377

它告诉您未命名模块中的类正在尝试访问不同的命名模块中的类: javafx.graphics .但是，后一个模块不会将所需的包导出到至少未命名的模块。查看错误消息和给定的类名，我们可以推断未命名模块中的类是 JavaFX 媒体实现的一部分。这表明该类应该在 javafx.media 中模块。那为什么错误会提到未命名的模块呢？
未命名模块是类路径上所有类所属的模块。这意味着 javafx.media模块被放在类路径上并失去了它的身份。这样做的结果是 javafx.graphics 声明的所有合格的导出/打开指令。授予 javafx.media 的模块模块所需的访问不再适用 - 因此 IllegalAccessError .
但是......你使用了模块路径
从您在问题中提供的命令行中，我们可以看到 javafx-media-11.jar文件被放置在模块路径( -p )上。那么问题是什么？该问题是由于将媒体 JAR 文件同时放置在模块路径和类路径上而导致的，同时无法确保 javafx.media模块被解析为模块。
模块解析的算法由 java.lang.module 描述。包文档。基本上，它从一组根模块开始，然后递归地枚举 requires 指令。根模块由 --add-modules 决定和 --module论据。您的代码不是模块化的，这意味着您不使用 --module ，你有:

--add-modules javafx.controls,javafx.graphics

换句话说，没有任何根模块直接或间接需要 javafx.media模块，因此它永远不会被解决。由于这些类也在类路径上，它们仍然可以找到，但现在在未命名的模块中。如果您还没有在类路径上放置 JavaFX 依赖项，那么您将获得 ClassNotFoundException .

解决方案
解决方案很简单:确保 javafx.media模块解决。至少有两种方法可以实现这一点:

在您的 --add-modules 中包含该模块论据。

--add-modules javafx.controls,javafx.media

请注意，您不需要指定 javafx.graphics模块，因为它会被其他模块隐式拉入；两者 javafx.controls和 javafx.media要求 javafx.graphics .同样的一般推理也适用于 javafx.base在这种情况下的模块。
Getting Started with JavaFX指南展示了如何在每个主要 IDE(即 IntelliJ、Eclipse 和 NetBeans)和构建工具(即 Maven 和 Gradle)中为 JavaFX 配置 VM 选项。

使您自己的代码模块化并添加必要的 requires 指令。

module app {
    requires javafx.controls;
    requires javafx.media;

    // replace with your Application class' package
    exports com.example.app to javafx.graphics;
}

然后确保使用 --module 启动您的应用程序.
注意合格导出到javafx.graphics . This is required为了让 JavaFX 反射性地实例化您的应用程序类。有类似要求(合格opens)for FXML controllers和其他需要私有(private)反射访问的 API。

还有另一种选择:将所有内容放在类路径上，包括 JavaFX 模块，并完全忽略 JPMS 模块。如果你这样做，你的主类 绝不能是 Application 的子类.您必须创建一个单独的启动器类来简单地启动 JavaFX。 警告:这种方法是 not supported .