In Java, a final method is a method that cannot be overridden by a subclass. A final method can be declared with the final keyword. Once a method is declared as final, it cannot be overridden by a subclass.

Here's an example of using a final method in Java:

class MyClass {
    public final void printMessage() {
        System.out.println("Hello World!");
    }
}

class MySubclass extends MyClass {
    // this will generate a compile-time error, as the final method cannot be overridden
    public void printMessage() {
        System.out.println("Goodbye World!");
    }
}

In the example above, printMessage() is declared as a final method in the MyClass class. The printMessage() method cannot be overridden by a subclass. In the MySubclass class, attempting to override the printMessage() method will generate a compile-time error.

There are a few benefits of using final methods:

• final methods can prevent unintended changes to a method's behavior in a subclass.
• final methods can improve code safety and stability by preventing unintended method overrides.
• final methods can improve code performance by allowing the compiler to make certain optimizations.

It's important to note that a final method can still be inherited by a subclass, and the subclass can still call the final method. The final keyword only prevents the method from being overridden by a subclass.