java.lang.NoClassDefFoundError

[yyyyyc1]

java.lang.NoClassDefFoundError: net/rebeyond/behinder/core/ShellService at java.lang.Class.getDeclaredMethods0(Native Method) at java.lang.Class.privateGetDeclaredMethods(Class.java:2701) at java.lang.Class.getDeclaredMethods(Class.java:1975) at javafx.fxml.FXMLLoader$ControllerAccessor.addAccessibleMethods(FXMLLoader.java:3508) at javafx.fxml.FXMLLoader$ControllerAccessor.access$4000(FXMLLoader.java:3340) at javafx.fxml.FXMLLoader$ControllerAccessor$1.run(FXMLLoader.java:3459) at javafx.fxml.FXMLLoader$ControllerAccessor$1.run(FXMLLoader.java:3452) at java.security.AccessController.doPrivileged(Native Method) at javafx.fxml.FXMLLoader$ControllerAccessor.addAccessibleMembers(FXMLLoader.java:3451) at javafx.fxml.FXMLLoader$ControllerAccessor.getControllerMethods(FXMLLoader.java:3411) at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2565) at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2446) at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3249) at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3210) at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3183) at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3159) at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3139) at javafx.fxml.FXMLLoader.load(FXMLLoader.java:3132) at net.rebeyond.behinder.ui.Main.start(Main.java:18) at com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$8(LauncherImpl.java:863) at com.sun.javafx.application.PlatformImpl.lambda$runAndWait$7(PlatformImpl.java:326) at com.sun.javafx.application.PlatformImpl.lambda$null$5(PlatformImpl.java:295) at java.security.AccessController.doPrivileged(Native Method) at com.sun.javafx.application.PlatformImpl.lambda$runLater$6(PlatformImpl.java:294) at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95) at com.sun.glass.ui.win.WinApplication._runLoop(Native Method) at com.sun.glass.ui.win.WinApplication.lambda$null$4(WinApplication.java:185) at java.lang.Thread.run(Thread.java:750) Caused by: java.lang.ClassNotFoundException: net.rebeyond.behinder.core.ShellService at java.net.URLClassLoader.findClass(URLClassLoader.java:387) at java.lang.ClassLoader.loadClass(ClassLoader.java:418) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:355) at java.lang.ClassLoader.loadClass(ClassLoader.java:351) ... 28 more 运行时报如下错误，希望大佬们帮忙解答一下，感谢！