JAR file runtime: failed to load main-class manifest attribute from ......

When you double-click the packaged JAR file to run it, the following error occurs: failed to load main-class manifest attribute from..., which is caused by the portal program that has not been set to run.

Right-click your jar file, select Open Method -- WinRAR -- open the META-INF folder, double-click the manifest. after opening the MF file, you will find that there is only manifest-version: 1.0, and there is no main-class: XXX configuration.

Solution ------------------

Re-open your eclipse, select the project that requires export, right-click Export, and select JAVA -- JAR File

After selecting the project to be exported, click Next --- next to go to the following page:

Note the main class here: (you certainly do not have any text information), Click Browse, select your main function, and then finish.