feat: Enhance email validation and Gmail domain detection in Email2 class

- Prompted user to enter an email address via Scanner.
- Improved email validation by checking both presence of '@' and that '.' appears after '@'.
- Extracted:
  - Username (substring before '@')
  - Domain name (substring after '@')
- Displayed extracted username and domain.
- Checked whether the domain:
  - Starts with "gmail" (case-insensitive)
  - Is exactly "gmail.com" (case-insensitive), by parsing substring before first '.'
- Handled cases where domain is malformed (i.e., no '.' after '@').
- Closed Scanner to prevent resource leak.

This update improves robustness in email parsing and provides accurate checks for Gmail domains.

Signed-off-by: Somesh diwan <[email protected]>

Author: Someshdiwan

Section6StringClassPrinting/src/Email2.java

@@ -34,7 +34,6 @@ public static void main(String[] args) {
         } else {
             System.out.println("Invalid email format. Please enter a valid email address.");
         }
-
         scanner.close();
     }
-}
+}