Java Utility Functions - Password Generation and Validation

Function 1: Generate a random password that's 7 characters. The random password MUST have 1 lowercase, 1 uppercase, 1 digit, and 1 symbol (valid symbols are ! @ # $ % *

Method signature should be
public static String generatePassword()

Function 2: Validate a passed in password. This password will be between 7 and 20 characters. It must comply with at least 3 of the following 4 rules: 1) at least 1 capital 2) at least one lowercase 3) at least 1 digit 4) at least 1 symbol (see above for valid symbols). If the password is too long or too short, return false. If it only meets 2 of the rules, return false. If it meets 3 or 4 of the rules, return true.

Method signature should be
public static boolean validatePassword(String password)

1. package password;
2. 
   
3. import java.util.Arrays;
4. import java.util.Collection;
5. import java.util.Collections;
6. import java.util.Random;
7. import java.util.regex.Matcher;
8. import java.util.regex.Pattern;
9. 
   
10. public class RandomPassword
11. {
12. private static String password;
15. // Method for gnerating random password each time
16. public static String generatePassword()
17. {
18. password="";
19. String temp[] = new String[7];
20. char []number = new char[]{'0','1','2','3','4','5','6','7','8','9'};
21. char []lowerCase = new char[]{'a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z'};
22. char []upperCase = new char[]{'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z'};
24. char []symbol = new char[]{'!','@','#','$','%','*'};
25. char []allCase = new char[]{'0','1','2','3','4','5','6','7','8','9','a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p',
26. 'q','r','s','t','u','v','w','x','y','z','A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U',
27. 'V','W','X','Y','Z','!','@','#','$','%','*'};
28. Random random = new Random();
29. int position = random.nextInt(10);
30. temp[0] = ""+number[position];
32. position = random.nextInt(26);
33. temp[1] = ""+lowerCase[position];
35. position = random.nextInt(26);
36. temp[2] = ""+upperCase[position];
38. position = random.nextInt(6);
39. temp[3] = ""+symbol[position];
41. for(int i=0;i<3 i="" span="">
42. {
43. position = random.nextInt(68);
44. temp[4+i] = "" +allCase[position];
45. }
47. // Suffle Your password
48. Collections.shuffle(Arrays.asList(temp));
50. // temp[] to String
51. for(String pass : temp)
52. password=password+pass;
55. return password;
56. }
59. //Method for validate password
61. public static boolean validatePassword(String password)
62. {
63. int flag=0;
64. // Validate Length 
65. if(password.length()<7 password.length="">20)
66. return false;
68. Pattern p = Pattern.compile("[a-z]");
69. Matcher m = p.matcher(password);
70. while(m.find())
71. {
72. flag++;
73. break;
74. }
75. 
    
76. p = Pattern.compile("[A-Z]");
77. m = p.matcher(password);
78. while(m.find())
79. {
80. flag++;
81. break;
82. }
83.  
84. p = Pattern.compile("\\d");
85. m = p.matcher(password);
86. while(m.find())
87. {
88. flag++;
89. break;
90. }
91.  
92. p = Pattern.compile("['!','@','#','$','$',''%','*']");
93. m = p.matcher(password);
94. while(m.find())
95. {
96. flag++;
97. break;
98. }
99.  
100.  
101. if(flag==0 || flag==1 || flag==2)
102. return false;
103.  
104. if(flag==3 || flag==4)
105. return true;
106.  
108. return true;
109. }
110. public static void main(String[] args) {
111. System.out.println("passwors id "+RandomPassword.generatePassword());
112. System.out.println(RandomPassword.validatePassword("aaaAaa)aa"));
113. }
114. }

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