Getclassloader() returns null, getclassloader() gets null

One 、 Problem description

adopt getClassLoader() Way to obtain jar Resources in the package , It's empty ：

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

Use ClassGraph, Can be changed to package name , See if you can get ：

        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(" file ：" + path);
            });
        }

Two 、 resolvent

No access to resources , Basically, the path is wrong , perhaps ClassLoader incorrect , The other problem is jar There's something wrong with the bag ,jar The directory does not exist in the package , adopt 7zip You can see ：

7z l xxxx.jar

FALSE jar Package directory :

Correct jar Package directory ：