Can you name the main types of collection structures and their implementations?

Main types of collection structures in Java and their implementations:

• List — an ordered set of elements, allows duplicates.

  • ArrayList — based on an array, fast access by index.
  • LinkedList — doubly linked list, efficient insertions and deletions.

• Set — a collection of unique elements, without a specific order.

  • HashSet — based on a hash table, fast search.
  • LinkedHashSet — preserves insertion order.
  • TreeSet — a sorted collection based on a tree.

• Map — stores key-value pairs.

  • HashMap — fast access by key.
  • LinkedHashMap — preserves insertion order.
  • TreeMap — sorted by keys.

• Queue — a collection for storing elements in processing order.

  • LinkedList — implements the Queue interface.
  • PriorityQueue — elements are extracted in order of priority.

Example of using ArrayList:

List<String> list = new ArrayList<>();
list.add("Hello");
list.add("World");
System.out.println(list.get(0)); // Will output "Hello"