assertFalse(pattern.matcher("image/png").matches());
        assertFalse(pattern.matcher("image/gif").matches());
    }

    @Test
    public void test_fsFileRulePattern_xhtmlXml() {
        // Test that application/xhtml+xml is correctly matched
        Pattern pattern = Pattern.compile(FS_FILE_RULE_PATTERN);
        assertTrue(pattern.matcher("application/xhtml+xml").matches());
    }