	@Test(expected = InvalidImplementationException.class)
	public void testBackupFile() {

		String content = FileUtil.readFile("testing.txt");
		FileUtil.backupFile(new File("src/test/resources/testing.txt"));
		String content2 = FileUtil.readFile("~testing.txt");
		Assert.assertEquals(content, content2);

		try {
			FileUtil.backupFile(new File("test/missing.txt"));
			fail("No Exception thrown with missing file.");
		} catch (Exception e) {
			// do nothing
		}

	}