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 maintains elements in the insertion order?

  1. HashSet

  2. LinkedHashMap

  3. TreeSet

  4. PriorityQueue

The correct answer is: LinkedHashMap

The other options, HashSet, TreeSet, and PriorityQueue, have no inherent order in which the elements are maintained. So, insertion order wouldn't be a factor in those collections. LinkedHashMap, on the other hand, implements the Map interface and uses a combination of a doubly-linked list and a hash table to maintain the entries in a predictable order based on the order of insertion. Therefore, elements are maintained in the insertion order in a LinkedHashMap.