1. Create a new directory (such as the lib directory) under the project and copy xxx.jar to that directory.
2. Open the build in the plugin.xml tab, check the xxx.jar in the lib directory in the Binary build, and add xxx.jar in the Extra ClassPath Entries.
3. On the Build page of the plugin.xml tab, Under Binary Build on the left, tick the output directory (bin) of your program and the directory (lib) where your jar is located, so that the exported files will include your compiled files and third-party libraries.
4. Then switch to the Runtime page of the plugin, and add the output directory (bin) of your program and all the jar files (lib/hello.jar) you want to include in the Classpath in the lower right corner. This is basically done