getClassLoader() returns null, getClassLoader() gets empty

1. Problem description

Obtain the resources in the jar package through getClassLoader(), which is empty:

this.getClassLoader().getResources("com/xxxx/test/Start.class").hasMoreElements();
this.getClassLoader().getResourceAsStream("test.txt");

Using ClassGraph, you can change it to the package name to see if you can get it:

        try (ScanResult scanResult = new ClassGraph().acceptPackages("com.xxx.xxx.xxx").scan()) {
    
    
            scanResult.getAllResources().forEachByteArrayIgnoringIOException((io.github.classgraph.Resource res, byte[] content) -> {
    
    
                String path = res.getPath();
                System.out.println("文件：" + path);
            });
        }

Two, the solution

The resource cannot be obtained, basically the path is wrong, or the ClassLoader is wrong. Another problem is that there is a problem with the jar package. There is no directory in the jar package. You can view it through 7zip:

7z l xxxx.jar

Wrong jar package directory:

Correct jar package directory: