How can you use default methods to add new functionality to an existing interface without breaking existing implementations?

hard📝 Application Q9 of 15

Java - Interfaces

AAdd a new default method with a body to the interface.

BCreate a new interface extending the old one.

CRemove all existing methods and add new ones.

DAdd a new abstract method to the interface.

Step-by-Step Solution

Solution:

Step 1: Understand interface evolution
Adding abstract methods breaks existing implementations as they must implement new methods.
Step 2: Use default methods for backward compatibility
Default methods provide a body, so existing classes are not forced to implement them.
Final Answer:
Add a new default method with a body to the interface. -> Option A
Quick Check:
Default methods enable interface evolution without breaking code [OK]

Quick Trick: Use default methods to add features without breaking code [OK]

Common Mistakes:

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