Sync Factory Method, Abstract Factory, Builder, Prototype to Java 25; fix post/code mismatches

01-creational/factory-method/Main.java

@@ -1,17 +1,23 @@
 package factorymethod;
 
 public class Main {
+
     public static void main(String[] args) {
-        System.out.println("=== Factory Method Pattern Demo ===\n");
 
-        NotificationService[] services = {
-            new EmailService("alice@example.com"),
-            new SmsService("+1-555-0123"),
-            new PushService("device-token-abc123")
-        };
+        // The client only knows about NotificationSender (the Creator)
+        NotificationSender sender;
 
-        for (NotificationService service : services) {
-            service.notifyUser("Your order #1042 has been shipped!");
-        }
+        sender = new EmailSender();
+        sender.notify("alice@example.com", "Your order has shipped!");
+
+        sender = new SmsSender();
+        sender.notify("+1-555-0100", "OTP: 482910");
+
+        sender = new PushSender();
+        sender.notify("device-token-xyz", "New message from Bob");
+
+        // Adding Slack: just swap the creator. Client code doesn't change.
+        sender = new SlackSender();  // new class, nothing else touched
+        sender.notify("#alerts", "CPU usage above 90%");
     }
 }