The program will output random strings containing numbers [0-9] and letters [a-z,A-Z].
The numbers in the code map to UniCode characters (for a full Unicode chart see here).
An explanation of the code is as follows:
- Generate random numbers within the range 48 (unicode for 0) to 122 (unicode for z).
- Only allow numbers less than 57 (the digits 0-9) or greater than 65 and less than 90 (letters A-Z) or great than 97 (the letters A-Z).
- Map each number to a char.
- Stop when you have the required length of the string.
- Collect the chars produced into a StringBuilder
- Turn the StringBuilder in a String and return
For random.ints(48,122) upper bound should be 123, because it exclusive
ReplyDeleteAlso (i<57 || i>65) && (i <90 || i>97) should be
Delete(i < 58 || i > 64) && (i < 91 || i > 96)
finally, to avoid of unnecessary boxing and unboxing
Deleterandom.ints(48,123)
.filter(i -> (i < 58) || (i > 64 && i < 91) || (i > 96))
.limit(length)
.collect(StringBuilder::new, (sb, i) -> sb.append((char) i), StringBuilder::append).toString());