Collection：

1. AbstractCollection<E> Class AbstractCollection is an abstract implementation of the Collection interface. 
2. AbstractList<E> AbstractList is an abstract implementation of the List interface, optimized for a backing store which supports random access. 
3. AbstractQueue<E> This class provides skeletal implementations of some Queue operations. 
4. AbstractSequentialList<E> AbstractSequentialList is an abstract implementation of the List interface. 
5. AbstractSet<E> An AbstractSet is an abstract implementation of the Set interface. 
6. ArrayBlockingQueue<E> A bounded blocking queue backed by an array. 
7. ArrayDeque<E> Resizable-array implementation of the Deque interface. 
8. ArrayList<E> ArrayList is an implementation of List, backed by an array. 
9. BlockingDeque<E> A Deque that additionally supports blocking operations that wait for the deque to become non-empty when retrieving an element, and wait for space to become available in the deque when storing an element. 
10. BlockingQueue<E> A Queue that additionally supports operations that wait for the queue to become non- empty  when retrieving an element, and wait for space to become available in the queue when storing an element. 
11.  ConcurrentLinkedQueue<E> An unbounded thread-safe queue based on linked nodes. 
12.ConcurrentSkipListSet<E> A scalable concurrent NavigableSet implementation based on a ConcurrentSkipListMap. 
13. CopyOnWriteArrayList<E> A thread-safe random-access list. 
14. CopyOnWriteArraySet<E> A Set that uses an internal CopyOnWriteArrayList for all of its operations. 
DelayQueue<E extends Delayed> An unbounded blocking queue of Delayed elements, in which an element can only be taken when its delay has expired. 
16. Deque<E> A linear collection that supports element insertion and removal at both ends. 
17. EnumSet<E extends Enum<E>> An EnumSet is a specialized Set to be used with enums as keys. 
18. HashSet<E> HashSet is an implementation of a Set. 
19. LinkedBlockingDeque<E> An optionally-bounded blocking deque based on linked nodes. 
20. LinkedBlockingQueue<E> An optionally-bounded blocking queue based on linked nodes. 
21. LinkedHashSet<E> LinkedHashSet is a variant of HashSet. 
22. LinkedList<E> LinkedList is an implementation of List, backed by a doubly-linked list. 
23. List<E> A List is a collection which maintains an ordering for its elements. 
24. NavigableSet<E> A SortedSet extended with navigation methods reporting closest matches for given search targets. 
25 PriorityBlockingQueue<E> An unbounded blocking queue that uses the same ordering rules as class PriorityQueue and supplies blocking retrieval operations. 
26 PriorityQueue<E> A PriorityQueue holds elements on a priority heap, which orders the elements according to their natural order or according to the comparator specified at construction time. 
27 Queue<E> A collection designed for holding elements prior to processing. 
28 Set<E> A Set is a data structure which does not allow duplicate elements. 
29 SortedSet<E> SortedSet is a Set which iterates over its elements in a sorted order. 
30 Stack<E> Stack is a Last-In/First-Out(LIFO) data structure which represents a stack of objects. 
31 SynchronousQueue<E> A blocking queue in which each insert operation must wait for a corresponding remove operation by another thread, and vice versa. 
32 TreeSet<E> TreeSet is an implementation of SortedSet. 
33 Vector<E> Vector is an implementation of List, backed by an array and synchronized. 

Map

List

set 只能有一个NULL 

Queue