Java Collections Compiler

Examples included

• Run the arraylist example
• Run the hashmap example
• Run the hashset example
• Run the sort list example
• Run the stack example
• Run the queue example
• Run the word count example

Practical tips

• Code to interfaces: List<Integer> list = new ArrayList<>(), not ArrayList<Integer>.
• For LIFO, prefer ArrayDeque over the legacy Stack class.
• Use Collections.unmodifiableList() to expose read-only views safely.

Common questions

Which List should I use?

ArrayList for random access. LinkedList for frequent insert/remove at the front.

Stack vs ArrayDeque?

ArrayDeque is faster and not synchronized. Use it as your default stack.