He dialed 7 next.
Working with files in raw Java requires FileInputStream , BufferedReader , and manual resource closing. Hutool reduces 10 lines of code to 1. hutool 39
No need to guess content types manually. He dialed 7 next
// String to primitive int num = Convert.toInt("123"); long[] arr = Convert.toLongArray("1,2,3"); long[] arr = Convert.toLongArray("1