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

Which of these is not a direct benefit of using generics with container classes?

1. Preventing insertion of incorrect type at compile time

2. Eliminating the need for casts when fetching items

3. Providing cleaner syntax

4. Increasing execution speed of programs

The correct answer is: Increasing execution speed of programs

When using generic container classes, two primary benefits are preventing insertion of incorrect types at compile time and eliminating the need for casts when fetching items. This is because generics allow for type checking at compile time, reducing the likelihood of errors and simplifying the code required to access items in the container. While generics may contribute to cleaner syntax and potentially improve execution speed in certain situations, those are not primary or direct benefits of using generics with container classes. In fact, depending on the specific implementation and usage, generics may sometimes incur a slight decrease in execution speed. Therefore, D is not a direct benefit of using generics with container classes and is the correct answer.