Spring FileUrlResource isWritable method returns true if URL protocol is not indicating a file

if add testcase @Test void test() throws IOException { Resource resource = new FileUrlResource(new URL("https://spring.io/")); assertThat(resource.isReadable()).isFalse(); } the former code cannot pass. Then I restricted FileUrlResource must be contructed with a URL about file.

Comment From: jhoeller

I've addressed this somewhat differently, exclusively relying on getFile() resolution (which could be overridden in subclasses) and not checking the URL protocol in the isWritable() implementation at all anymore.

Thanks for spotting this - and thanks for the pull request, in any case!