In a project for college we have to implement participants which can exchange messages via a channel. This channel has to be realised as a EventBus (Guava).
When I'm trying to register a listener (part1) to the eventbus (channel):
channel.register(part1);
the following Exception appears in the console.
Exception in thread "main" java.lang.reflect.InvocationTargetException
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:566)
at java.base/sun.launcher.LauncherHelper$FXHelper.main(LauncherHelper.java:1051)
Caused by: java.lang.RuntimeException: Exception in Application start method
at javafx.graphics/com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:900)
at javafx.graphics/com.sun.javafx.application.LauncherImpl.lambda$launchApplication$2(LauncherImpl.java:195)
at java.base/java.lang.Thread.run(Thread.java:834)
Caused by: java.lang.NoClassDefFoundError: com/google/common/util/concurrent/internal/InternalFutureFailureAccess
at java.base/java.lang.ClassLoader.defineClass1(Native Method)
at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:1016)
at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:1095)
at java.base/java.security.SecureClassLoader.defineClass(SecureClassLoader.java:206)
at java.base/jdk.internal.loader.BuiltinClassLoader.defineClass(BuiltinClassLoader.java:759)
at java.base/jdk.internal.loader.BuiltinClassLoader.findClassInModuleOrNull(BuiltinClassLoader.java:680)
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(BuiltinClassLoader.java:605)
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:579)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
at java.base/java.lang.ClassLoader.defineClass1(Native Method)
at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:1016)
at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:1095)
at java.base/java.security.SecureClassLoader.defineClass(SecureClassLoader.java:206)
at java.base/jdk.internal.loader.BuiltinClassLoader.defineClass(BuiltinClassLoader.java:759)
at java.base/jdk.internal.loader.BuiltinClassLoader.findClassInModuleOrNull(BuiltinClassLoader.java:680)
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(BuiltinClassLoader.java:605)
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:579)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
at java.base/java.lang.ClassLoader.defineClass1(Native Method)
at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:1016)
at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:1095)
at java.base/java.security.SecureClassLoader.defineClass(SecureClassLoader.java:206)
at java.base/jdk.internal.loader.BuiltinClassLoader.defineClass(BuiltinClassLoader.java:759)
at java.base/jdk.internal.loader.BuiltinClassLoader.findClassInModuleOrNull(BuiltinClassLoader.java:680)
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(BuiltinClassLoader.java:605)
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:579)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
at com.google.common/com.google.common.cache.LocalCache$LoadingValueReference.<init>(LocalCache.java:3472)
at com.google.common/com.google.common.cache.LocalCache$LoadingValueReference.<init>(LocalCache.java:3476)
at com.google.common/com.google.common.cache.LocalCache$Segment.lockedGetOrLoad(LocalCache.java:2134)
at com.google.common/com.google.common.cache.LocalCache$Segment.get(LocalCache.java:2045)
at com.google.common/com.google.common.cache.LocalCache.get(LocalCache.java:3951)
at com.google.common/com.google.common.cache.LocalCache.getOrLoad(LocalCache.java:3974)
at com.google.common/com.google.common.cache.LocalCache$LocalLoadingCache.get(LocalCache.java:4958)
at com.google.common/com.google.common.cache.LocalCache$LocalLoadingCache.getUnchecked(LocalCache.java:4964)
at com.google.common/com.google.common.eventbus.SubscriberRegistry.getAnnotatedMethods(SubscriberRegistry.java:173)
at com.google.common/com.google.common.eventbus.SubscriberRegistry.findAllSubscribers(SubscriberRegistry.java:164)
at com.google.common/com.google.common.eventbus.SubscriberRegistry.register(SubscriberRegistry.java:74)
at com.google.common/com.google.common.eventbus.EventBus.register(EventBus.java:186)
at commands.Commands.createChannel(Commands.java:243)
at persistence.HSQLDB.resetDatabase(HSQLDB.java:482)
at gui.GUI.start(GUI.java:101)
at javafx.graphics/com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$9(LauncherImpl.java:846)
at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runAndWait$12(PlatformImpl.java:455)
at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$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$$$capture(InvokeLaterDispatcher.java:96)
at javafx.graphics/com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java)
at javafx.graphics/com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at javafx.graphics/com.sun.glass.ui.win.WinApplication.lambda$runLoop$3(WinApplication.java:174)
... 1 more
Caused by: java.lang.ClassNotFoundException: com.google.common.util.concurrent.internal.InternalFutureFailureAccess
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:581)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
... 55 more
Can anyone help me?
The guava.jar is added as a library. It has to be something with the implementation of the jar and the ClassLoader.
You'll need to download that jar and put it on your classpath, too.
(As Onur Baştürk suggests, this happens automatically with some build tools.)