Create PasswordGenerator.java

PasswordGenerator.java

@@ -0,0 +1,137 @@
+import java.util.*;
+
+public class PasswordGenerator {
+    private static final String UPPERCASE_LETTERS = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+    private static final String LOWERCASE_LETTERS = "abcdefghijklmnopqrstuvwxyz";
+    private static final String NUMBERS = "0123456789";
+    private static final String SYMBOLS = "!@#$%^&*()_-+=<>?";
+
+    public static void main(String[] args) {
+        Scanner scanner = new Scanner(System.in);
+
+        // User Input and Preferences
+        int passwordLength = getPasswordLength(scanner);
+        String characterTypes = getCharacterTypes(scanner);
+
+        // Generating a Random Password
+        String generatedPassword = generatePassword(passwordLength, characterTypes);
+
+        // Password Strength
+        String passwordStrength = getPasswordStrength(generatedPassword);
+
+        // Display or Copy Password
+        System.out.println("Generated Password: " + generatedPassword);
+        System.out.println("Password Strength: " + passwordStrength);
+
+        scanner.close();
+    }
+
+    private static int getPasswordLength(Scanner scanner) {
+        int length = 0;
+        boolean validInput = false;
+
+        while (!validInput) {
+            System.out.print("Enter the desired password length: ");
+            String input = scanner.nextLine();
+
+            try {
+                length = Integer.parseInt(input);
+                if (length >= 8) {
+                    validInput = true;
+                } else {
+                    System.out.println("Password length should be at least 8 characters.");
+                }
+            } catch (NumberFormatException e) {
+                System.out.println("Invalid input. Please enter a valid integer.");
+            }
+        }
+
+        return length;
+    }
+
+    private static String getCharacterTypes(Scanner scanner) {
+        System.out.println("Select the character types to include in the password:");
+        System.out.println("1. Uppercase letters");
+        System.out.println("2. Lowercase letters");
+        System.out.println("3. Numbers");
+        System.out.println("4. Symbols");
+        System.out.print("Enter the corresponding numbers separated by commas (e.g., 1,3): ");      // Edit: 10/14/2023  10:04 AM (Changed println to print)
+
+        String input = scanner.nextLine();
+
+        Set<Character> characterSet = new HashSet<>();
+        String[] choices = input.split(",");
+
+        for (String choice : choices) {
+            switch (choice.trim()) {
+                case "1":
+                    addCharactersToSet(characterSet, UPPERCASE_LETTERS);
+                    break;
+                case "2":
+                    addCharactersToSet(characterSet, LOWERCASE_LETTERS);
+                    break;
+                case "3":
+                    addCharactersToSet(characterSet, NUMBERS);
+                    break;
+                case "4":
+                    addCharactersToSet(characterSet, SYMBOLS);
+                    break;
+                default:
+                    System.out.println("Invalid choice: " + choice);
+                    break;
+            }
+        }
+
+        StringBuilder characterTypes = new StringBuilder();
+        for (char c : characterSet) {
+            characterTypes.append(c);
+        }
+
+        return characterTypes.toString();
+    }
+
+    private static void addCharactersToSet(Set<Character> characterSet, String characters) {
+        for (char c : characters.toCharArray()) {
+            characterSet.add(c);
+        }
+    }
+
+    private static String generatePassword(int length, String characterTypes) {
+        StringBuilder password = new StringBuilder();
+
+        Random random = new Random();
+        for (int i = 0; i < length; i++) {
+            int randomIndex = random.nextInt(characterTypes.length());
+            password.append(characterTypes.charAt(randomIndex));
+        }
+
+        return password.toString();
+    }
+
+    private static String getPasswordStrength(String password) {
+        boolean hasUppercase = false;
+        boolean hasLowercase = false;
+        boolean hasNumber = false;
+        boolean hasSymbol = false;
+
+        for (char c : password.toCharArray()) {
+            if (Character.isUpperCase(c)) {
+                hasUppercase = true;
+            } else if (Character.isLowerCase(c)) {
+                hasLowercase = true;
+            } else if (Character.isDigit(c)) {
+                hasNumber = true;
+            } else {
+                hasSymbol = true;
+            }
+        }
+
+        if (password.length() >= 12 && hasUppercase && hasLowercase && hasNumber && hasSymbol) {
+            return "Strong";
+        } else if (password.length() >= 8 && (hasUppercase || hasLowercase || hasNumber || hasSymbol)) {
+            return "Medium";
+        } else {
+            return "Weak";
+        }
+    }
+}