How do you use backward compatibility strategies with a simple code example?

Backward compatibility is an important aspect of software development, especially in programming languages like Java. It ensures that newer versions of software can still run applications built on older versions, which helps maintain usability and reduces the need for constant updates. Here’s a simple example to illustrate a backward compatibility strategy in Java:

public class OldFeature {
        public void display() {
            System.out.println("This is an old feature.");
        }
    }

    // New class using old class
    public class NewFeature extends OldFeature {
        @Override
        public void display() {
            super.display(); // Calls the old feature's display method
            System.out.println("This is a new feature that builds on the old one.");
        }
    }

    public class Main {
        public static void main(String[] args) {
            OldFeature old = new OldFeature();
            old.display(); // Outputs old feature message

            NewFeature anew = new NewFeature();
            anew.display(); // Outputs both old and new feature messages
        }
    }