hi1Q0Yh0

1import java.util.Random;
2
3public class RandomPasswordGenerator {
4    private static final String CAPITAL_LETTERS =
5        "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
6    private static final String SMALL_LETTERS =
7        "abcdefghijklmnopqrstuvwxyz";
8    private static final String DIGITS = "0123456789";
9    //private static final String SPECIAL_CHARS =
10    //    "~!@#$%^&*()_+=`{}[]\\|':;.,/?<>";
11    private static final String SPECIAL_CHARS =
12        "!@#$%&.";
13
14    private static final String ALL_CHARS =
15        CAPITAL_LETTERS + SMALL_LETTERS + DIGITS + SPECIAL_CHARS;
16    private static Random rnd = new Random();
17    public static void main(String[] args) {
18        StringBuilder password = new StringBuilder();
19
20        // Generate two random capital letters
21        for (int i=1; i<=4; i++) {
22            char capitalLetter = generateChar(CAPITAL_LETTERS);
23            insertAtRandomPosition(password, capitalLetter);
24        }
25
26        // Generate two random small letters
27        for (int i=1; i<=4; i++) {
28            char smallLetter = generateChar(SMALL_LETTERS);
29            insertAtRandomPosition(password, smallLetter);
30        }
31
32        // Generate one random digit
33        for (int i=1; i<=3; i++) {
34            char digit = generateChar(DIGITS);
35            insertAtRandomPosition(password, digit);
36            }
37
38        // Generate 3 special characters
39        for (int i=1; i<=3; i++) {
40            char specialChar = generateChar(SPECIAL_CHARS);
41            insertAtRandomPosition(password, specialChar);
42        }
43
44        // Generate few random characters (between 0 and 7)
45        int count = rnd.nextInt(8);
46        for (int i=1; i<=count; i++) {
47            char specialChar = generateChar(ALL_CHARS);
48            insertAtRandomPosition(password, specialChar);
49        }
50
51        System.out.println(password);
52    }
53
54    private static void insertAtRandomPosition(
55            StringBuilder password, char character) {
56        int randomPosition = rnd.nextInt(password.length()+1);
57        password.insert(randomPosition, character);
58    }
59
60    private static char generateChar(String availableChars) {
61        int randomIndex = rnd.nextInt(availableChars.length());
62        char randomChar = availableChars.charAt(randomIndex);
63        return randomChar;
64    }
65
66}
67