java - 类未发现异常？

Question

好吧，我很困惑。昨天它工作得很好。今天突然我开始收到错误。主框架打开得很好，前几个按钮也可以工作。只是最后三个突然不起作用了。当我尝试单击这些按钮(应该打开新窗口)时，出现以下错误

Exception in thread "AWT-EventQueue-0" java.lang.NoClassDefFoundError: my/freelancebillingapp/paidStatusUI at my.freelancebillingapp.FreelanceBillingUI.paidClicked(FreelanceBillingUI.java:251) at my.freelancebillingapp.FreelanceBillingUI.access$200(FreelanceBillingUI.java:18) at my.freelancebillingapp.FreelanceBillingUI$3.mouseClicked(FreelanceBillingUI.java:89) at java.awt.AWTEventMulticaster.mouseClicked(AWTEventMulticaster.java:253) at java.awt.Component.processMouseEvent(Component.java:6266) at javax.swing.JComponent.processMouseEvent(JComponent.java:3267) at java.awt.Component.processEvent(Component.java:6028) at java.awt.Container.processEvent(Container.java:2041) at java.awt.Component.dispatchEventImpl(Component.java:4630) at java.awt.Container.dispatchEventImpl(Container.java:2099) at java.awt.Component.dispatchEvent(Component.java:4460) at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4574) at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4247) at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4168) at java.awt.Container.dispatchEventImpl(Container.java:2085) at java.awt.Window.dispatchEventImpl(Window.java:2475) at java.awt.Component.dispatchEvent(Component.java:4460) at java.awt.EventQueue.dispatchEvent(EventQueue.java:599) at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269) at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161) at java.awt.EventDispatchThread.run(EventDispatchThread.java:122) Caused by: java.lang.ClassNotFoundException: my.freelancebillingapp.paidStatusUI at java.net.URLClassLoader$1.run(URLClassLoader.java:200) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:188) at java.lang.ClassLoader.loadClass(ClassLoader.java:307) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301) at java.lang.ClassLoader.loadClass(ClassLoader.java:252) at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:320) ... 24 more

与昨天工作正常时相比，代码没有任何变化。我可以打开所有单独的 java 文件，它们都可以正常打开，代码与以前相同。发生了什么？

Answer 1

什么是my.freelancebillingapp.paidStatusUI？这是一个类(class)吗？如果是，它应该以大写字母开头，但这实际上是一个旁注。但是，您可能在某个地方遇到了案例问题。可以用文件名吗？