实现
单向队列
栈结构
SortedSet
LinkedList
+ transient int size = 0;+ transient Node first;+ transient Node last;
（1）允许元素重复（2）记录元素先后添加的顺序
Vector
# Object[] elementData;# int elementCount;# int capacityIncrement;
+ synchronized int size();+ synchronized boolean isEmpty()+ synchronized void addElement(E obj)+ synchronized boolean add(E e)
Queue
+ boolean add(E e);+ boolean offer(E e);+ E remove();+ E poll();+ E element();+ E peek();
List
int size();boolean add(E e);boolean remove(Object o);boolean isEmpty();..........
Iterable
Iterator iterator();
HashSet
+ Iterator iterator();+ int size();+ boolean isEmpty();+ boolean contains(Object o);+ Object clone();..................
Collection
双向队列
（1）不允许元素重复（2）不记录元素先后添加的顺序
继承
Set
+ int size();+ boolean isEmpty();+ Iterator iterator();+ T[] toArray(T[] a);+ boolean equals(Object o);+ int hashCode();............
ArrayList
- static final int DEFAULT_CAPACITY = 10;- static final Object[] EMPTY_ELEMENTDATA = {};- transient Object[] elementData;- int size;
LinkedHashSet
NavigableSet
+ E lower(E e);+ E floor(E e);+ E ceiling(E e);+ Iterator iterator();
数组结构
TreeSet
+ Iterator iterator();+ int size();+ boolean isEmpty();+ boolean contains(Object o);- void writeObject(java.io.ObjectOutputStream s)- void readObject(java.io.ObjectInputStream s)...................
Deque
ArrayDeque
- transient E[] elements;- transient int head;- transient int tail;- static final int MIN_INITIAL_CAPACITY = 8;
- T[] copyElements(T[] a);+ void addFirst(E e);+ void addLast(E e);+ E removeFirst();+ ArrayDeque clone()
Stack
+ E push(E item)+ synchronized E pop()+ synchronized E peek()+ boolean empty()+ synchronized int + search(Object o)
实现：栈、单向队列、双向队列、双向链表
存储数据的容器，定义了集合框架的一组算法
实现了哈希算法
实现了红黑树算法，提高了查询速度
实现的哈希算法、链表算法（保证元素添加顺序）
