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

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Dive into the depths of Java with our quiz based on "Thinking in Java, Fourth Edition" by Bruce Eckel. Test your knowledge, solidify concepts, and prepare for certification with challenging questions and insightful feedback.

Each practice test/flash card set has 50 randomly selected questions from a bank of over 500. You'll get a new set of questions each time!

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Which collection type is not allowed to have duplicate elements?

  1. List

  2. Set

  3. Queue

  4. Map

The correct answer is: Set

Set is a collection type that is specifically designed to not allow duplicate elements. Lists are ordered collections that allow duplicates. Queues are similar to lists, but allow for the removal of elements from the front of the collection. Maps are key-value pair collections that can have duplicate values but not duplicate keys. Therefore, none of the other options are correct for a collection type that does not allow for duplicate elements.