public static String getMimeType(Path file) {
		try {
			return Files.probeContentType(file);
		} catch (IOException ignore) {
			// issue#3179，使用OpenJDK可能抛出NoSuchFileException，此处返回null
			return null;
		}
	}
@Test
	public void getMimeOf7zTest(){
		String contentType = FileUtil.getMimeType("a001.7z");
		assertEquals("application/x-7z-compressed", contentType);
	}