Final class

Prevents the class from being extended and reused

Use when you want to protect core logic from being changed by subclassing.

eg

                  final class Logger {
                        public function log($msg) {
                                echo "Log: $msg";
                        }
                 }


                // ❌ This will throw an error
                class FileLogger extends Logger {
                // Error: Cannot extend final class
                }

                        

Final function

Prevents the method from being overridden in subclasses

Use when you want to allow inheritance but lock specific methods from being changed.

                        class Animal {
                                final public function sound() {
                                        echo "Some generic sound";
                                }
                        }

                        class Dog extends Animal {
                                // ❌ This will throw an error
                                public function sound() {
                                        echo "Bark!";
                                }
                        }