Finishing bonus parts

src/main/java/BonusExercises.java

@@ -20,7 +20,7 @@ public class BonusExercises {
             - Each segment (between dots) must follow same hyphen rules
      */
     public boolean validateEmail(String email) {
-        String regex = ""; // todo
+        String regex = "^[a-zA-Z0-9_+-]+(?:\\.[a-zA-Z0-9_+-]+)*@(?:[a-zA-Z0-9-]+\\.)+[a-zA-Z0-9-]+$";
         Pattern pattern = Pattern.compile(regex);
         Matcher matcher = pattern.matcher(email);
 
@@ -38,11 +38,31 @@ public class BonusExercises {
 
         If no match for a date is found in the string, return null.
     */
-    public String findDate(String string) {
-        // todo
+    public String findDate(String text) {
+        if (text == null || text.isBlank()) {
+            return null;
+        }
+
+        String dateRegex =
+                "\\b(?:"
+                        + "\\d{4}[-/](?:0[1-9]|1[0-2])[-/](?:0[1-9]|[12]\\d|3[01])"
+                        + "|"
+                        + "(?:0[1-9]|[12]\\d|3[01])/(?:0[1-9]|1[0-2])/\\d{4}"
+                        + "|"
+                        + "(?:0[1-9]|1[0-2])/(?:0[1-9]|[12]\\d|3[01])/\\d{4}"
+                        + ")\\b";
+
+        Matcher matcher = Pattern.compile(dateRegex).matcher(text);
+
+        if (matcher.find()) {
+            return matcher.group();
+        }
+
         return null;
     }
 
+
+
     /*
         given a string, implement the method to detect all valid passwords
         then, it should return the count of them
@@ -54,8 +74,60 @@ public class BonusExercises {
         - has no white-space in it
      */
     public int findValidPasswords(String string) {
-        // todo
-        return -1;
+        int count = 0;
+
+        for (int i = 0; i <= string.length() - 8;) {
+
+            int bestJ = -1;
+
+            for (int j = i + 8; j <= string.length(); j++) {
+                String tempPassword = string.substring(i,j);
+
+                if (tempPassword.contains(" ")){
+                    continue;
+                }
+
+                boolean hasSpecialCharacter = false;
+                boolean hasDigit = false;
+                boolean hasLowercase = false;
+                boolean hasUppercase = false;
+
+
+                String specialChars = "!@#$%^&*";
+                String digits = "1234567890";
+                String lowerCases = "abcdefghijklmnopqrstuvwxyz";
+                String upperCases = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+
+                for (int k = 0; k < tempPassword.length(); k++) {
+
+                    char currentChar = tempPassword.charAt(k);
+
+                    if (specialChars.contains(String.valueOf(currentChar))){
+                        hasSpecialCharacter = true;
+                    } else if (upperCases.contains(String.valueOf(currentChar))) {
+                        hasUppercase = true;
+                    } else if (lowerCases.contains(String.valueOf(currentChar))) {
+                        hasLowercase = true;
+                    } else if (digits.contains(String.valueOf(currentChar))) {
+                        hasDigit = true;
+                    }
+                }
+
+                if (hasDigit && hasLowercase && hasUppercase && hasSpecialCharacter){
+                    count++;
+                    i = j;
+                    bestJ = j;
+                    break;
+                }
+
+            }
+
+            if (bestJ == -1){
+                i++;
+            }
+
+        }
+        return count;
     }
 
     /*
@@ -64,9 +136,41 @@ public class BonusExercises {
 
         note: your implementation should be case-insensitive, e.g. Aba -> is palindrome
      */
+    public boolean isPalindrome(String word) {
+        if (word.length() == 1){
+            return false;
+        }
+        String lowerWord = word.toLowerCase();
+        StringBuilder mutableInverse = new StringBuilder(lowerWord.length());
+
+        for (int i = lowerWord.length() - 1; i >= 0; i--){
+            mutableInverse.append(lowerWord.charAt(i));
+        }
+
+        String inverseOfWord = mutableInverse.toString();
+        return lowerWord.equals(inverseOfWord);
+    }
+    
     public List<String> findPalindromes(String string) {
         List<String> list = new ArrayList<>();
-        // todo
+        String[] wordsArray = string.split("\\s+");
+
+
+        for (String s : wordsArray){
+
+            String finalS = s;
+            if (finalS.endsWith(",")) {
+                finalS = finalS.substring(0, finalS.length() - 1);
+            }
+            if (finalS.isEmpty()) {
+                continue;
+            }
+
+            if (isPalindrome(finalS)){
+                list.add(finalS);
+            }
+        }
+
         return list;
     }