@Test
    void testInvalidJar() {
        try {
            FilesApplicationPackage.getComponents(new File("src/test/cfg/application/validation/invalidjar_app"));
            fail();
        } catch (IllegalArgumentException e) {
            assertEquals("Error opening jar file 'invalid.jar'. Please check that this is a valid jar file",
                    e.getMessage());
        }
    }
Tests that an invalid jar is identified as not being a jar file
config-model/src/test/java/com/yahoo/config/model/ApplicationDeployTest.java