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

How might the provided null object pattern be considered an application of the Proxy design pattern?

1. Because it uses reflection to intercept method calls

2. Because it delegates method calls to a hidden real object

3. Because it requires explicit type casting in client code

4. It's not; null object and Proxy are unrelated patterns

The correct answer is: Because it delegates method calls to a hidden real object

The null object pattern involves creating a "null" object that handles requests, while the Proxy pattern involves creating an intermediary object that controls access to another object. In this case, the null object acts as the hidden real object that the Proxy delegates method calls to. Option D is incorrect because the two patterns are related in this instance. Option A is incorrect because reflection is not explicitly mentioned in the question. Option C is incorrect because explicit type casting is not a requirement for either pattern.