Later I found out that there was a problem with the jar package I imported in the struts2 project. The jar package of my original struts2 project was damaged when the U disk was moved between the USB disk and the computer, which caused my subsequent struts2 projects (all of which had to import the jar package from the original project). Copied) also uses a damaged jar package and cannot run.
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
Later I found out that there was a problem with the jar package I imported in the struts2 project. The jar package of my original struts2 project was damaged when the U disk was moved between the USB disk and the computer, which caused my subsequent struts2 projects (all of which had to import the jar package from the original project). Copied) also uses a damaged jar package and cannot run.