22.12 - Custom Functional Interface Example
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Practice Questions
Test your understanding with targeted questions
Define a functional interface with a method 'calculate'.
💡 Hint: Use @FunctionalInterface annotation.
What does a lambda expression enable you to do?
💡 Hint: Think about how you might implement a new operation.
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Interactive Quizzes
Quick quizzes to reinforce your learning
What is a functional interface?
💡 Hint: Remember the definition we covered.
True or False: Lambda expressions can only call methods defined in the same class.
💡 Hint: Think about the scope of lambda expressions.
1 more question available
Challenge Problems
Push your limits with advanced challenges
Create a functional interface 'Calculator' that can perform any mathematical operation such as addition, subtraction, multiplying, and division. Implement your interface using lambda expressions and test it with various operations.
💡 Hint: Consider designing each operation as a separate lambda expression.
Design an application that requires a functional interface to validate user input. Create a method that accepts a lambda for validation and uses it to check conditions like range and format.
💡 Hint: Think about the common criteria for user inputs.
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