Mastering Java: The Ultimate Quiz for 'Thinking in Java'

What is the purpose of the Map.entrySet() method?

1. To delete all entries

2. To return a set view of the mappings

3. To clear the map

4. To check if a map is empty

The correct answer is: To return a set view of the mappings

The Map.entrySet() method is used to retrieve all of the key-value pairs in a map in the form of a Set of Map.Entry objects. Option A is incorrect because the method does not delete any entries; it only returns a set view. Similarly, option C is incorrect because the method does not clear the map. Option D is also incorrect as the method does not check if the map is empty; it simply returns a Set.