What are common mistakes developers make with final keyword?

Using the final keyword in Java can lead to common mistakes among developers. Here are some of them:

• Final Variables: Developers often forget that final variables can only be assigned once. This might lead to compilation errors if they try to reassign a final variable.
• Final Method Overriding: When a method is declared final, it cannot be overridden in subclasses. This could lead to unanticipated issues when subclasses are intended to modify method behavior.
• Final Classes: A class marked as final cannot be subclassed. Developers sometimes fail to realize that this limits extension and inheritance options, which could restrict design flexibility.
• Final Parameters: Final parameters within methods cannot be reassigned. While this can be useful for clarity, developers may inadvertently expect to modify these parameters.

Here’s an example of using the final keyword incorrectly:

        public final class MyClass {
            final int myNumber = 10;

            public void changeValue() {
                // This will cause a compilation error
                myNumber = 20; // Error: cannot assign a value to final variable myNumber
            }

            public final void display() {
                System.out.println("This is a final method.");
            }
        }