Practice Examples Of Predefined Functional Interfaces (1.2.2)

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6 sample questions

Question 1.
What is a functional interface?
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Think about how they relate to lambda expressions.
Question 2.
Name one predefined functional interface in Java.
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Consider interfaces used in multitasking or GUI programming.
3Question 3.
What is a functional interface?
- An interface with multiple abstract methods
- An interface with one abstract method
- An abstract class
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Remember the definition of a functional interface.
4Question 4.
True or False: Runnables can return a value.
- True
- False
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Think of the method signature of Runnable.
Question 5.
Implement a custom Comparator for sorting integers in descending order and demonstrate its usage with a list of integers.
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How do you reverse the natural order?
Question 6.
Write a small program using both Runnable and Callable, demonstrating the differences in their functionality.
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What does each method return or do when executed?

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