Question

我学习Java和我创建了我的第一个Java项目，这仅仅是UPI的演示应用程序。我的项目在IDE（使用Netbeans IDE）中可以完美运行，但是当我创建JAR文件并尝试执行该文件时，它显示此错误：

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
    at javax.swing.ImageIcon.<init>(Unknown Source)
    at swift.upi.LoginUI.initComponents(LoginUI.java:350)
    at swift.upi.LoginUI.<init>(LoginUI.java:27)
    at swift.upi.Welcome.nextBtnMouseClicked(Welcome.java:133)
    at swift.upi.Welcome.access$000(Welcome.java:14)
    at swift.upi.Welcome$1.mouseClicked(Welcome.java:67)
    at java.awt.Component.processMouseEvent(Unknown Source)
    at javax.swing.JComponent.processMouseEvent(Unknown Source)
    at java.awt.Component.processEvent(Unknown Source)
    at java.awt.Container.processEvent(Unknown Source)
    at java.awt.Component.dispatchEventImpl(Unknown Source)
    at java.awt.Container.dispatchEventImpl(Unknown Source)
    at java.awt.Component.dispatchEvent(Unknown Source)
    at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
    at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
    at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
    at java.awt.Container.dispatchEventImpl(Unknown Source)
    at java.awt.Window.dispatchEventImpl(Unknown Source)
    at java.awt.Component.dispatchEvent(Unknown Source)
    at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
    at java.awt.EventQueue.access$500(Unknown Source)
    at java.awt.EventQueue$3.run(Unknown Source)
    at java.awt.EventQueue$3.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
    at java.awt.EventQueue$4.run(Unknown Source)
    at java.awt.EventQueue$4.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
    at java.awt.EventQueue.dispatchEvent(Unknown Source)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.run(Unknown Source)

当我尝试执行任何事件（例如鼠标单击事件）时，会发生此错误。正因为如此，我才能够运行我的内部IDE项目。试图解释一个简单易用的方式问题和解决方案。我给的链接到我的项目为了方便起见，找到 here。

谢谢。

Answer 1

正如卡洛斯（Carlos）的评论所暗示的那样，问题在于找到LoginUI.java第350行中引用的图标/图像。

将压缩后的项目内容与类I guess 的代码进行比较，可能是文件名及其大小写出现了问题。

代码说/swift/upi/Name logo.jpg
该目录包含名为Name Logo.jpg的文件

尝试将l更改为L。另外-我建议您在文件名中避免使用空格字符。

无法执行JAR文件

1 个答案: