develop branch

AP1403 - RegEx/src/main/java/Exercises.java

@@ -5,55 +5,106 @@
 
 public class Exercises {
 
-    /*
-        complete the method below, so it will validate an email address
-     */
     public boolean validateEmail(String email) {
-        String regex = ""; // todo
+        String regex = "^[a-zA-Z0-9_+&*-]+(?:\\.[a-zA-Z0-9_+&*-]+)*@(?:[a-zA-Z0-9-]+\\.)+[a-zA-Z]{2,7}$";
         Pattern pattern = Pattern.compile(regex);
         Matcher matcher = pattern.matcher(email);
 
         return matcher.matches();
     }
 
-    /*
-        this method should find a date in string
-        note that it should be in british or american format
-        if there's no match for a date, return null
-     */
     public String findDate(String string) {
-        // todo
+        String regex = "\\b(\\d{1,2}[/-]\\d{1,2}[/-]\\d{2,4}|\\d{4}[/-]\\d{1,2}[/-]\\d{1,2})\\b";
+        Pattern pattern = Pattern.compile(regex);
+        Matcher matcher = pattern.matcher(string);
+
+        while (matcher.find()) {
+            String date = matcher.group();
+
+            String[] parts;
+            if (date.contains("/")) {
+                parts = date.split("/");
+            } else if (date.contains("-")) {
+                parts = date.split("-");
+            } else {
+                continue;
+            }
+
+            int day, month, year;
+            if (parts[0].length() == 4) {
+                year = Integer.parseInt(parts[0]);
+                month = Integer.parseInt(parts[1]);
+                day = Integer.parseInt(parts[2]);
+            } else {
+                day = Integer.parseInt(parts[0]);
+                month = Integer.parseInt(parts[1]);
+                year = Integer.parseInt(parts[2]);
+            }
+
+            if (month < 1 || month > 12) {
+                continue;
+            }
+            if (day < 1 || day > 31) {
+                continue;
+            }
+            if ((month == 4 || month == 6 || month == 9 || month == 11) && day > 30) {
+                continue;
+            }
+            if (month == 2) {
+                boolean isLeapYear = (year % 4 == 0 && year % 100 != 0) || (year % 400 == 0);
+                if (day > 29 || (day == 29 && !isLeapYear)) {
+                    continue;
+                }
+            }
+
+            return date;
+        }
+
         return null;
     }
 
-    /*
-        given a string, implement the method to detect all valid passwords
-        then, it should return the count of them
-
-        a valid password has the following properties:
-        - at least 8 characters
-        - has to include at least one uppercase letter, and at least a lowercase
-        - at least one number and at least a special char "!@#$%^&*"
-        - has no white-space in it
-     */
     public int findValidPasswords(String string) {
-        // todo
-        return -1;
-    }
+        String regex = "(?=\\S{8,})(?=\\S*[a-z])(?=\\S*[A-Z])(?=\\S*\\d)(?=\\S*[!@#$%^&*])\\S+";
+        Pattern pattern = Pattern.compile(regex);
+        Matcher matcher = pattern.matcher(string);
 
-    /*
-        you should return a list of *words* which are palindromic
-        by word we mean at least 3 letters with no whitespace in it
+        int count = 0;
+        while (matcher.find()) {
+            String password = matcher.group();
+            if (!password.matches(".*\\s.*")) {
+                count++;
+            }
+        }
+        return count;
+    }
 
-        note: your implementation should be case-insensitive, e.g. Aba -> is palindrome
-     */
     public List<String> findPalindromes(String string) {
         List<String> list = new ArrayList<>();
-        // todo
+
+        String regex = "\\b[a-zA-Z]{3,}\\b";
+        Pattern pattern = Pattern.compile(regex);
+        Matcher matcher = pattern.matcher(string);
+
+        while (matcher.find()) {
+            String word = matcher.group();
+            String lowerCaseWord = word.toLowerCase();
+
+            boolean isPalindrome = true;
+            int length = lowerCaseWord.length();
+            for (int i = 0; i < length / 2; i++) {
+                if (lowerCaseWord.charAt(i) != lowerCaseWord.charAt(length - 1 - i)) {
+                    isPalindrome = false;
+                    break;
+                }
+            }
+
+            if (isPalindrome) {
+                list.add(word);
+            }
+        }
+
         return list;
     }
-
     public static void main(String[] args) {
-        // you can test your code here
     }
 }