File inside jar is not visible for spring

I know this question has already been answered. However, for those using spring boot, this link helped me - https://smarterco.de/java-load-file-classpath-spring-boot/

However, the resourceLoader.getResource("classpath:file.txt").getFile(); was causing this problem and sbk's comment:

That's it. A java.io.File represents a file on the file system, in a directory structure. The Jar is a java.io.File. But anything within that file is beyond the reach of java.io.File. As far as java is concerned, until it is uncompressed, a class in jar file is no different than a word in a word document.

helped me understand why to use getInputStream() instead. It works for me now!

Thanks!

If your spring-context.xml and my.config files are in different jars then you will need to use classpath*:my.config?

More info here

Also, make sure you are using resource.getInputStream() not resource.getFile() when loading from inside a jar file.

In the spring jar package, I use new ClassPathResource(filename).getFile(), which throws the exception:

cannot be resolved to absolute file path because it does not reside in the file system: jar

But using new ClassPathResource(filename).getInputStream() will solve this problem. The reason is that the configuration file in the jar does not exist in the operating system's file tree,so must use getInputStream().

The error message is correct (if not very helpful): the file we're trying to load is not a file on the filesystem, but a chunk of bytes in a ZIP inside a ZIP.

Through experimentation (Java 11, Spring Boot 2.3.x), I found this to work without changing any config or even a wildcard:

var resource = ResourceUtils.getURL("classpath:some/resource/in/a/dependency");
new BufferedReader(
  new InputStreamReader(resource.openStream())
).lines().forEach(System.out::println);