我就学习GUI的JFrame里面查几个按钮而已,很奇怪的是 程序可以运行,也弹出来了我设计的窗口,但是我却看到了下图所示的小红八叉 这应该叫做编译器报错把?? 奇怪啊 怎么能运行了 还有错误呢 提示的错误是 :
Multiple markers at this line
- The serializable class Gui does not declare a static final serialVersionUID field of type long
- Access restriction: The type JFrame is not accessible due to restriction on required
library C:\Program Files\Java\jre1.8.0_25\lib\rt.jar