Feat: cache md5 file value

src/main/java/com/sheepit/client/Utils.java

@@ -68,21 +68,8 @@ public class Utils {
 	}
 	
 	public static String md5(String path_of_file_) {
-		try {
-			MessageDigest md = MessageDigest.getInstance("MD5");
-			InputStream is = Files.newInputStream(Paths.get(path_of_file_));
-			DigestInputStream dis = new DigestInputStream(is, md);
-			byte[] buffer = new byte[8192];
-			while (dis.read(buffer) > 0)
-				; // process the entire file
-			String data = convertBinaryToHex(md.digest());
-			dis.close();
-			is.close();
-			return data;
-		}
-		catch (NoSuchAlgorithmException | IOException e) {
-			return "";
-		}
+		Md5 md5 = new Md5();
+		return md5.get(path_of_file_);
 	}
 	
 	public static String convertBinaryToHex(byte[] bytes) {