The jar package is missing because the spring source code is imported into eclipse.
So download the spring released Spring-core jar package from the MAVEN repository.
To facilitate understanding of the directory structure, use the tree command:
tree [/F] >tree.txt
/F, full subdirectories/files are generated
├─pac_jar_cglib
│└─org
│└─springframework
│└─cglib
│
└─pac_jar_objenesis
└─org
└─springframework
└─objenesis
Select the folder with the green background, hold down the SHIFT key, and right-click here to open cmd. Enter the jar CVF Xxxxxx.jar * in the Command line window
If you enter command line cmd from the "pac_jar_objenesis" folder, execute the following command
jar CVF Spring-objenesis-repack-2.4.jar *
PS: where * All files in the directory are packaged into the jar file
It will generate Spring-objenesis-repack-2.4.jar
Follow the path of the missing jar package in Eclipse, the new jar that the backrest is wrapped in, the item is refreshed, and the problem is resolved.
Jar command to wrap the folder of class files